Neuroscience Exam 2

SAMPLE QUESTION - what brain area control emotional expression? a. ventral tegmental area b. amygdala c. orbiofrontal cortex d. brain stem

c. orbiofrontal cortex - emotional expression

SAMPLE QUESTION - which are NOT basic human emotions? a. embarrassment b. fear c. surprise d. fanatical devotion to the pope e. these are all emotions

d

SAMPLE QUESTION - NPY / AgRP neurons.... a. produce neuropeptide Y and agouti - related peptide b. stimulate appetite c. lower metabolism d. all of the above

d. all of the above

FEAR

- amygdala: recognition - hypothalamus: generates the raw feeling of fear - brain stem: powered

CHARLES WITMAN CASE

- an eagle scout, marine lance corporal, and a student at the university of Texas at Austin, he stabbed to death his mother and his wife on the morning of August 1, 1996 - he then took an arsenal to the top of the tower overlooking the university campus - after killing a receptionist and opening fire on four tourists, killing two, he killed fourteen people (plus one unborn child) and wounded twice that many - 3 austin police officers and a civilian stormed the tower and killed him

THE FOOD TASTES BLUE

- association brain areas mic inputs of different modalities - SYNESTHESIA: a stimulus in one modality creates a sensation in another: - someone said "this taste blue, but it normally taste green to me": - cross linked visual pathway with taste pathway - music -> colors - graphemes (number and letters) -> colors - speech sound -> taste - causes of synesthesia: - LSD - posterior temporal love seizures - results of blindness or deafness - occurs spontaneously

WHERE IS THAT SOUND COMING FROM?

- binaural cues detect sound location - COMPARE THE EARS: - INTENSITY DIFFERENCES: different loudness at the two ears - LATENCY DIFFERENCES: different arrival times for sounds at the ears - ACCURATE LOCALIZATION: requires process BOTH intensity and latency differences - SUPERIOR OLIVE: is our main sound localization nucleus

WE USE ALL THREE STRATEGIES

- brain counts the number of impulses or the amount of neurons responding - for a while there's no response: - when the very first action potential is sent - fires until it reaches about 150 and then it plateaus out - why does it plateau? - because that's as fast as a neuron can go - ESPS (stimulus intensity): - low threshold: 0 - medium threshold: 5 1/2 - high threshold: 11

REGULATION OF FOOD INTAKE

- brain integrates insulin and glucose levels with other signals to decide when to start/ stop eating - external factors: - emotions, food characteristics, lifestyle behaviors, environmental cues - things that can either increase or decrease your desire to eat - ex: if you're stressed you may have no appetite or you may eat more comfort foods - central signals - stimulants (NPY) and inhibits (delta- MSH) - peripheral signals: - glucose, insulin, ghrelin, leptin, cortisol) - things from your gut - as glucose rise you shouldn't be hungry, when they fall they make you hungry again - insulin job is to take glucose and put it into the blood stream

RECEPTIVE FIELD

- that part of the world a SENSORY NEURON response to - property of each SINGLE sensory neuron - differ in size, shape: - according to function - ex: the tongue is very sensitive to any touch - good at giving us a spatial map

quiz? intensity is to _____ as frequency is to ____

loudness, pitch

quiz ? which syndrome is likely to be caused by a mutation that increases opening of Na+ channels in free nerve endings?

man on fire

quiz ? where did charles whitman, the UT sniper, have a brain tumor?

next to his amygdala

quiz ? the correct pathway of auditory signals is from cochlea to auditory nerve to

superior olive, inferior colliculi, medial geniculate nucleus, auditory cortex

SAMPLE QUESTION - a fall in blood andiotensis II level.... a. makes one feel thirsty b. raises blood pressure c. occurs after eating salt d. none of the above

the answer is D. none of the above because a. if there is a fall of angiotensisn II then that means you are no longer thirsty b. raises blood pressure - angiotensin II does this c. not relative to this process

quiz? superficial tactile receptors mediate _____, whereas deeper receptors mediate ____

touch; vibration

quiz ? fourier analysis of an auditory stimulus determines its

frequencies

quiz ? touching a merkel disc in the skin always produces a...

graded potential

quiz ? Volley theory says:

groups of neurons follow the frequency of a sound at frequencies that a single neuron cannot

quiz ? threatening situations activate the

hypothalamus pituitary adrenal cortex axis

AUDITORY CORTEX ANALYZES SOUNDS IN TWO STREAMS

- "where" pathway: - dorsal part of the brain - "what" pathway: - ventral part of the brain

SENSORY INTEGRATION DISORDER - hypersensitivity to touch - hyposensitivity to touch

- 3 categories 1. HYPERSENSITIVITY TO TOUCH (STIMULUS AVOIDERS): - distressed by having face washed or hair or nails out - picky eater, only eats certain textures - refuses to walk barefoot on grass or sand, toe walks - common in people with autism 2. HYPOSENSITIVITY TO TOUCH ( STIMULUS SEEKERS): - craves touch, touches everything and everyone - hurts other children or pets while playing - may pinch, bite or bang own head

KIDS EATING DISORDER SURVEY (KEDS)

- 3,175 students in grades 5-8 surveyed: - 30% dieting - 10% fasting - 5% vomiting - 2% using diet pills

AMYGDALA - FEAR

- AMYGDALA: - participates in memory formation, especially emotional ones - people with amygdala damage are usually trusting - anxiety reducing drugs act on receptors in the amygdala - FMRIL fearful expression -> amygdala activation (RECOGNITION of fear)

SOMATOSENSORY CORTEX REORGANIZES AFTER AMPUTATION OF A HAND

- if sensory neurons lose their job then the neurons will take on another job

PAIN AND ITS DISORDERS

- pain is necessary for survival - to tell us something is wrong with us and to fix it if we can

THREE SYSTEMS

- sleep - limbic system - hypothalamus

AUDITORY HAIR CELLS

- thin fibers called TIP LINKS run across each hair cell's stereocilla

quiz ? humans are most sensitive to frequencies in the range of:

2,000 to 5,000 Hz

ALL SENSORY PROCESSING BEGINS IN RECEPTOR CELLS

- a stimulus to the receptor produces a GRADED POTENTIAL - if the potential is big enough, the receptor generated an ACTION POTENTIAL

PET IMAGING OF FEMALE ORGASM

- activation of the deep cerebellar nuceli - inhibition of orbitofrontal cortex

SEXUAL ORIENTATION - statistics - SOCIAL INFLUENCE HYPOTHESIS - BIOLOGICAL HYPOTHESIS

- 3.5% of American adults identify as lesbian, gay or bisexual. 0.3% are transgender - about 12 million Americans totally - suspected number is higher but people are in the closet - little support for SOCIAL INFLUENCE HYPOTHESIS: emphasizes home environment or early education as cause of homosexuality - BIOLOGICAL HYPOTHESIS: most homosexuals recall feeling "different" as early as 4 or 5 years - they show gender nonconformity during childhood: engaging in activities usually preferred by the other sex & preferring other sex companions

DSM - V CIRTERIA: EATING DISORDERS - ANOREXIA: - MORTALITY RATE - BULLIMIA

- ANOREXIA NERVOSA: refusal to maintain body weight: - fear of gaining weight - body image disturbance - Amenorrhea: period stops, body doesn't have enough energy to have a period and determines you're not eating enough for yourself let alone a baby - caused by thyroid gland - restricting or binge eating/ purging type - anorexia nervosa have the HIGHEST MORTALITY rate of any psychiatric disorder - 0.5% lifetime prevalence in women (0.05% in men) 10x more likely in women - BULIMIA: recurrent binge eating: - recurrent inappropriate compensatory behavior/ purging - at least 2x weak for 3 months

FOURIER TRANSFORM ANALYSIS

- ANY complex sound is a collection of simple sine waves added together - a word is spoken and activates different neurons because each word is different - how can the neurons and glial cells work together and work a mathematical analysis?: - auditory brains FIRST TASK is to discern what is noise and what is not

ANGIOTENSIN CASCADE

- Angiotensin II and its mirroring effects - if blood volume decreases, kidneys release renin, which triggers formation of angiotensin II - effects: 1. blood vessels constrict 2. cricumventricular organs trigger drinking 3. vasopressin is released 4. aldosterone is released

BRAIN AREAS INVOLVED IN EMOTION

- BRAINSTEM: (maybe the power): - LOCUS COERULEUS: - norepinephrine: emotional arousal, depression/ pleasure, stress - VTA, SUBSTANTIA NIGRA: - dopamine: exhilaration - ORBIOFRONTAL CORTEX: (maybe the controller): - inhibits raw emotion from amygdala, emotional expression - LIMBIC SYSTEM (the integrator): - hypothalamus: ANS reactions - amygdala: anger and fear, emotional memory - hippocampus: memory - cingulate gyrus: pain processing, empathy

HOW CAN INTENSITY OF A STIMULUS BE CODED? - CODING - what are the three strategies

- CODING: patterns of action potentials in a sensory system - strategies: 1. a SINGLE neuron can convey stimulus intensity by changing the FREQUENCY of its action potentials - a neuron could fire more frequently as we increase the intensity of the touch - the greater you push against the hair the more action potential 2. MULTIPLE neurons can act in parallel - as the stimulus strengthens, MORE neurons are recruited - the brain will count how many neurons are recruited/ firing - if 2 are firing then we assume there is more touch 3. DIFFERENT NEURONS respond to DIFFERENT RANGES (range fractionation) - we use all of these strategies

PAIN DISORDERS - CONGENITAL INSESNTIVITY TO PAIN - MAN OF FIRE SYNDROME/ CONGENITAL HYPERSENSITIVITY TO PAIN

- CONGENITAL INSENSITIVITY TO PAIN: inherited mutated sodium channel in pain fibers in dorsal root ganglia: - there is no pain - leads to autoamputations of digits: - children chew on fingers but if they're unsensitive to pain then they could chew off the tips of their fingers bc they never get the stimulus of pain that it hurts - why cant fire an action potential? - so you cant feel pain why?: - the voltage gated sodium channels are abnormal MAN ON FIRE SYNDROME: congenital HYPERSENSITIVITY to pain: - gain of function of sodium channels - more likely to trigger action potential - severe burning pain, erythema, triggered by mild warmth - autosomal dominant, 100% penetrant - mutation found in families in china, analyzed in new haven. families now identified in europe, USA and canada - cause: gain of function Na

SOMATOSENSORY CORTEX - THE HOMUNCULUS

- CORTICAL MAP: represent the innervation of a body region

NEURAL CIRCUITRY IN OTHER EMOTIONS - disgust - laughter - anterior cingulate cortex

- DISGUST: activated the INSULA. - guilt (inward disgust) - when we have a disgusting stimulus our insula lights up - LAUGHTER: activates the ORBIOFRONTAL FORTEX - ANTERIOR CINGULATE CORTEX: combines emotional, attentional, and body information in a conscious emotional experience

TREATMENT OF OBESITY (what works for sure) - eat less, calorie deficit - exercise

- EAT LESS: a daily deficit of 200 calories is reasonable. This is the most IMPORTANT part and the most difficult to do. eat until you're not hungry, then stop - this means lifestyle change for YEARS. self monitoring and social support are essential: - Japanese teach their children to stop eating when you're no longer hungry - americans teach their kids to stop eating when they don't want anymore - EXERCISE: a lot, strenuous aerobic activity for over 200 minutes per week for a long time with calories restriction work

EMOTIONS AND AROUSAL - EMOTIONS

- EMOTION: is an increase or decrese in physiological activity accompanied by feelings characteristics of the emotion - appraisal gives rise to arousal, behavior, facial/ postural expressions, and emotional feelings - arousal, behavior and expressions add to emotional feelings - emotional feelings influence appraisal, which further affects arousal, behavior, expressions and feelings - when you activates the ANS, it activates the rest of everything in the chart (run, fearful face, fear): implies activating any one of these things can activates the rest - Similarly, the feeling of fear makes you look at the environment to find something to fear aka fear can change you cognitive appraisal - cognitive appraisal (ex: danger) triggers: - ANS arousal - behavior (ex: run) - emotional expression (fearful face) - emotional feelings (fear)

PAIN BECOMES EMOTIONAL IN CINGULATE CORTEX (ACC)

- activity increases there, but not in the somatosensory cortex, as pain unpleasantness increases - painful heat stimulates somatosensory area and anterior cingulate cortex

AUTONOMIC: ACTIVATION DURING ACUTE STRESS (SKY DIVING)

- ENDOCRINE RESPONSE: each time you face your fear you gain more confidence to face it therefore dropping your response to fear because you don't feel as fearful anymore: - cortisol may be very high by the first jump out of a plane but by the 5th time cortisol will drop back to a normal level - testosterone will decrease the first jump and then rise back up to a normal level by the 2nd or 5th jump - epinephrine will increase during the first jump out of a plane then decrease back to the normal/ control level - why is this important?: - sometimes we have to face our fears the first time so we can stop being fearful of them after

FYI: COMEDIANDS CURSE

- FMRI activation of right ventromedial prefrontal cortex and left orbiofrontal cortex by exposure to cartoons with increasing funniness and violation of normal social norms: - the more social norms are violated the funnier the joke is

PERIPHERAL ORIGIN OF PAIN

- FREE NERVE ENDING (pain) in skin have specialized receptors to respond to temperature change, chemicals and tissue injury: - ice will decrease the pain and inflammation and less activation of pain receptors - not especially substance P - a neurotransmitter - trauma (wrist bone broken) - the broken bone slices and hurts the surrounding tissues - ripping the cells apart resulting in damage: - cells have chemicals inside of them - these chemicals are inside the cells but when the cells are damaged they are dumped outside to diffuse around local tissue - autoinfalmmatory pain meds block the production of some of these chemicals: - serotonin - K+ - Prostaglandins - Leukotrienes - pain activated the free nerve endings - the intensity of the pain is intense enough (broken bone in the wrist) triggers action potential to the brain - pass by the cell body into the spinal cord cross over to the brain: - thalamus first then stomata sensory cortex

ENERGY STORAGE/ UTILIZATION - GLUCOSE - GLYCOGEN - GLYCOGENESIS - LIPIDS

- GLUCOSE: is the principal fuel for energy - GLYCOGEN: is glucose for short term in liver: - glucose stored - GLYCOGENESIS: converting glucose to glycogen, using pancreas hormone insulin - LIPIDS: for long term storage, are FAT TISSUE

BASICS OF SOUND

- HERTZ (Hz): cycles per second of sound, perceived as pitch - AMPLITUDE or intensity: perceived as loudness - PURE TONE: tone of a single frequency (Hz) of vibration - MUSICAL TONE: modulated pure tones with repetition (rhythm) - NOISE: random sounds

SPATIAL ABILITY IS AFFECTED BY MASCULATION

- HIGH ESTROGEN LEVEL: is associated with: depressed spatial ability, enhanced speech and manual skill tasks - TESTOSTERONE: during 2nd trimester increases cerebral asymmetry via accelerated growth of the right hemisphere

HYPOVOLEMIC THIRST & OSMOTIC THIRST - HYPOVOLEMIC THIRST - OSMOTIC THIRST

- HYPOVOLEMIC THIRST: is stimulated by low extracellular or intravascular volume: - from blood loss, more commonly from sweating - OSMOTIC THIRST: is stimulated by high extracellular solute concentration: - happens every time you eat - triggers by salt molecule that you eat - salt hypertonic to the rest of the body - shift of the water thats already in the body

CHORNIC STRESS

- Harmful too - interferes with memory, appetite, sexual desire and performance - depletes energy and disrupts mood - increases body inflammation - compromises the immune system: - 6 years after 3 mile island nuclear accident in Pennsylvania, residents showed impaired concentration and lowered immune responses - hormone released during chronic stress suppresses immune system: - at rest: miRNAs balances out DAMPs - acute stress: adrenaline and NE cause immune cells to release DAMPs - after stress: balance is restored by cortisol - chronic stress: low grade excess production of DAMP or block of miRNAs

SEXUAL ORIENTATION: BRAIN'S ROLE IN HOMOSEXUALITY - INAH3 - SUPERCHIASMATIC NUCLEUS (SCN) - ANTERIOIR COMMISSURE (AC)

- INAH3: (third interstitial nucleus of the anterior hypothalamus) is female sized (SMALLER) in gay men - SUPERCHAISMATIC NUCLEUS (SCN) is LARGER IN GAY men than in heterosexual men and contains more vasopressin - secreting cells - ANTERIOR COMMISSURE (AC) is LARGER in GAY men and heterosexual women than in heterosexual men - gay men's verbal and spatial performance is MORE similar to WOMEN's than to heterosexual men's

FRONAL LOBE IN EMOTION

- LEFT FRONTAL ACTIVATION: behavioral approach. Emotions reuglated by this area are anger, joy - its job is to make the proper behavior approach according to which emotion you feel - RIGHT FRONTAL ACTIVATION: behavioral withdrawl. emotions regulated are fear, sadness - RIGHT FRONTAL LOBE: is more active during NEGATIVE emotions - LEFT HEMISPHERE: is more active during POSITIVE emotions

WE HAVE UNCONSCIOUS HEARING

- MAIN SOUND ROUTE: - conscious hearing - when you're asleep this pathway turns off - "BACK DOOR": - unconscious hearing - when you go to sleep you can hear things around you, your ears do not turn off but we do not feel like we are hearing because we are sleeping

SEX: IMPORTANT BRAIN AREAS FOR BOTH SEXES

- MEDIAL AMYGDALA: (MeA,: in the temporal lobe) - involved in sex, smell, aggression and emotions - one subarea is much larger in men - part that gives us motivation to have sex

PLEASURE/ HAPPINESS - medial forebrain bundle

- MEDIAL FOREBRAIN BUNDLE: tract rises from midbrain though the hypothalamus - contains many sites for self stimulation

CHRONIC PAIN REMODELS THE SPINAL CHORD

- NEUROGENIC PAIN: is due to INAPPROPRIATE SIGNALING of pain by neurons 1. post synaptic spinal cord neurons take up SUBSTANCE P, released during pain, and remodel their dendrites 2. OVERACTIVITY OF SYMPATHETIC INPUT -> dorsal horn neurons (light touch) become hyperexcitable: INCREASE spontaneous activity and response to all touch (light touch is now felt as pain), GABA INHIBITORY interneurons become EXCITATORY

BIOLOGICAL DETERMINATION OF GENDER

- ORGANIZING EFFECTS: mostly occur prenatally or shortly after birth: - they affect brain and body structure and are lifelong (genitals) - ACTIVATING EFFECTS: occur at any time in life: - come and go with hormone fluctuation or are long lasting, but are reversible (muscle mass) - testosterone is main organizing hormone in HUMAN brain development

BIOLOGICAL ORIGINS OF AGGRESSION - two types.... what are they?? - AGGRESSION - reactive aggression - proactive aggression

- aggression: behavior that is intended to harm - two types of aggression: - REACTIVE aggression: is impulsive, provoked, emotional - PROACTIVE AGGRESSION: is premeditated, unprovoked, emotionless

OSMOTIC THIRST - OSMOSENSORY NEURONS - OVLT NEURONS

- OSMOSENSORY NEURONS in anterior hypothalamus (OVLT) respond to rise in blood osmotic pressure - powered by too many osmols in the blood stream: - osmols are just salt molecules in the brain - we need receptors in the service of the neuron that says oh we have shrunk - their cell membranes shrink, opening mechanical gated Na+ channels - osmosensory neurons: - greater concentration of solutes outside the cell than outside - water flows out of the cell, equalizing the solute concentration and shrinking the cell - OVLT NEURONS: respond to increased osmotic pressure by causing the pituitary to release antidiuretic hormone (like vasopressin)

SPINOTHALAMIC SYSTEM TRANSMITS PAIN AND TEMPERATURE

- PERIAQUEDUCTAL GRAY in the midbrain involved in PAIN PERCEPTION; OPIOD RECEPTORS - spinothalmic tract - cingulate cortex - somatosensory cortex - you step on a nail - free nerve endings are activated by various chemicals - ESPS occurs enough polarization happens in the dorsal ganglia - triggers an action potential, travels up the brain through the brain stem - makes a connection with the PERIAQUEDUCTAL GRAY: - in the midbrain involved in PAIN PERCEPTION; OPIOD RECEPTORS - placed in the midbrain involving pain perception: - contains opiod receptors - travels to the somatosensory cortex: - intense pain can be emotional if the pain system is activated for too long (interacts with cingulate cortex) - in conclusion...... - spinothalamic tract: cells heads north with pain information - periaqueductal gray: nucleus along this pathway that contains opiod receptors and can serve as a pin blocking site - cingulate cortex: adds emotion to the sense of pain - somatosensory cortex: where pain perception actually occurs

PREFRONTAL (ORBIOFRONTAL) CORTEX

- PREFRONTAL CORTEX: is the final destination for the brain's information about emotion BEFORE ACTION IS TAKEN - main job is to ask what am i going to do about this emotion? - am i going to regulate it or not - prefrontal cortex judges our behavior and its consequences: - people with damage here UNDERSTAND moral and social rules but CAN'T APPLY the rules in their own loves - impulsiveness - people who sustain damage EARLY IN LIFE NEVER LEARN these rules and are motivated only to avoid punishment - sociopathy - abnormalities in PFC are associated with aggression, depression, schizophrenia

POST TRAUMATIC STRESS DISORDER - what is it - symptoms - treatments - what is the natural course of PTSD?

- PTSD develops in response to a stressful event of exceptionally threatening or catastrophic nature: assault, car wrecks, rape - symptoms include: - reexperiencing (ex: flashbacks, nightmares) - avoiding people or situations associated with event - hyperarousal symptoms (panic) - treatments: behavioral desensitization (let me take you back to that time...) - propranolol - ecstacy - DURATION OF SYMPTOMS FOR PTSD: - usual onset of symptoms a few days after the event - many recover without treatment within months/ years of event (50% natural remission by 2 years), but some may have significant impairment of social occupational functioning - treatment means that about 20% more people with PTSD recover - generally 33% remain symptomatic for 3 years or longer with greater risk of secondary problems

EMOTIONAL SOCIOPATHY

- SOCIOPATHS: are incapable of remorse - they may commit very violent acts

NEUROGENIC PAIN: REFLEX SYMPATHETIC DYSTROPHY

- STAGE 1: onset of severe pain limited to the site of injury: - increased sensitivity of skin to touch - localized swelling - usually lasts a few weeks then subsides - STAGE 2: pain becomes more severe and more diffuse - swelling tends to spread - hair and nails become brittle - muscle wasting begins

TWO PARALLEL TOUCH SYSTEMS - TONIC RECEPTORS - PHASIC RECEPTORS

- TONIC RECEPTORS: slow or no decline in action potential frequency - PHASIC RECEPTORS: adapt quickly by decreased frequency: - act like an alarm to warn you about any touch sensation - our sensory cortex is organized this way too

EMOTIONAL EXPRESSIONS ACROSS CULTURES

- The facial effect of emotions is not voluntary so we are triggered to make a facial expression but before it is facially expressed your frontal cortex determine how you want to express it according to the situation - Elicitors (actual or anticipated situation, recollections, etc) -> facial affect program (facial morot programs for happiness, surprise, anger, fear etc.) (limbic system) -> mediation by culture specific display rules (exaggerate, minimize, counteract, camouflage) (frontal cortex) -> end result

CASE

- a 6 year old boy was hospitalized at enfants malades hospital in Paris because of seizures. During his first 3 days, he exhibited fatigue, incoherent speech, cisual hallucinations, verbal agnosia and behavior disorders - one month later he lost speech and developed visual agnosia, memory deficits, and perseverative behavior. His aggression increased and he became hyperoral. Behavior alternated between apathy and hyperactivity - why?: Kluver - Bucy syndrome: - an emotional change - the amygdala, in the temporal lobe, is a key structure in fear - removal of temporal lobes in monkeys has a taming effect; they are socially clueless: - the maygdala is important in recognizing dangerous situations - the amygdala receives input from the outside world: - stimuli goes through the thalamus to the sensory cortex and creates the feeling of fear - then to the hippocampus and into the amygdala that creates the emotional behavior, autonomic response and hormonal response

THYROID HORMONE CONTAINS IODINE AND DEPENDS ON ITS SUPPLY - goiter - cretinism

- a GOITER is swelling of the thyroid gland from iodine deficiency - the body is deprived of iodine therefore deprived of thyroid hormone - early thyroid deficiency results in CRETINISM with mental retardation

CASE - pain insensitivity

- a canadian women born with PAIN INSENSITIVITY had no other sensory deficits and was quite intelligent - despite early training to avoid damaging situations, she developed progressive degeneration of her joints and spinal vertebrae, causing skeletal deformation, infection and death at age 28

EMOTIONS HAVE CHARACTERISTIC FACIAL EXPRESSIONS

- a pan cultural pan human process to recognize emotions by facial expressions

POSED FACIAL EXPRESSIONS CHANGE HOW WE INTERPRET OUR ENVIRONMENT

- a stimulus is more painful when making a sad face - cartoons are rated as funnier during induced smiling - women given botox are less able to frown and have less negative mood: - when they imitate an angry expression they have less amygdala activity - a women treated with botox is unable to produce the facial expression of anger and show little activation of the amygdala and produces much greater amygdala activation

HOW DOES THIS SOUND INFORMATION GET TO THE BRAIN?

- amplifiers - transducers

TRPC IS THE SPICE OF LIFE

- capsaicin: the "hot" in chillies, activates C fibers via TRVP1 and is neurotoxic - FYI: - melts body fat - slows atherosclerosis - lowers blood pressure - fights diabetes - lowers body weight - all good to avoid cardiometabolic diseases - capsaicin is banned in equestrian sports - hypersensitive horses are more motivated to jump hurdles. In 2008 olympics, 4 horses were disqualified

DO YOU HEAR WHAT I HEAR?

- cats hear high frequencies that humans don't: - to hear birds at higher frequencies - elephants hear low frequencies that humans don't: - to hear big animals who vibrate at lower frequencies

EACH AUDITORY CORTEX NEURON HAS A PREFERRED FREQUENCY

- cells ' specialize' in what frequency they fire to - some cells are less 'picky' than others (the red one here)

LEVELS OF SEX DETERMINATION

- chromosomal sex - gonadal sex - internal sex organs - external sex organs - brain sex - gender identity - gender preference - 7 levels: not all the same in any of us - how many genders are there?: maybe 2 to the power of 7 = 128

CHRONIC PAIN - how long does it last - neurogenic pain - psychogenic pain

- chronic pain persists EVEN LONG AFTER an injury is healed - pain signals remain active in CNS MONTHS TO YEARS - emotional effects include depression, anger, fear of reinjury: - NEUROGENIC PAIN: pain resulting from damage to nerves - PSYCHOGENIC PAIN: pain not due to disease, injury or any visible damage

ECB SYSTEM HELPS RESILIENCE DURING AND / OR AFTER STRESS

- chronic stress (cortisol) impairs 2-AG synthesis - habituation to stress is due to INCREASED eCB system activity

BRAIN CONTROLS OF DRINKING

- circulating angiotensin II acts in the SUBFORNICAL ORGAN to signal other brain sites to initiate drinking: - connected to the motor system, change of though to motivate you to drink something to satisfy your thirst

ROMANTIC LOVE - study

- college students in new love: while being scanned, looked at a photo of their beloved one: - RIGHT VENTRAL TEGMENTAL AREA (as in drug craving) became very active: - maybe thats love or maybe lust - long married couples who describe themselves as still in love also light up their VTA: maybe the VTA is more than lust, becomes a part of long love - we don't know if romantic love is an emotion but it certainly taps into some emotions

HIPPOCAMPAL DAMAGE IN A STRESSED MONKEY

- compare number of cells between arrows in a control monkey (left) and a monkey that died of apparent stress (right) - repeated stress causes: - prefrontal cortex to shrink - hippocampus to shrink - and amygdala to increase in size and then the cells die

NEUROTRANSMITTERS AND SEX BEHAVIORS

- dopamine (DA)+: - DA activity in MPOA motivates sex behavior in both sexes, especially in men - drugs that increase DA increase sexual activity in humans - increasing levels of DA produce erection in males, then ejaculation - serotonin (5HT) (-): - injecting SSRI into LH increases time before male rats copulate again - both men and women complain SSRIs impair their sexual ability

TWO PARALLEL TACTICLE SYSTEMS

- dorsal column: medial lemniscal pathway: - touch, vibration, two point discrimnation, proprioception - dorsal root axon -> dorsal column -> dorsal column nuclei -> medial lemniscus -> cerebral cortex - spinothalamic pathway: - pain, temperature, some touch - dorsal root axon -> lateral spinothalamic tract ->

HORMONES AFFECT BEHAVIOR IN MANY WAYS

- endocrine pathology mimics psychiatric disorders - CUSHING DISEASE: results from long term excess glucocorticoids, with fatigue and depression , in severe cases can cause psychosis - dallas news interviews high school students, coaches and parents in north Texas: 25 % described their encounters with illegal steroid use

HUNGER DIETS, WHY THEY DON'T WORK

- energy expenditure is adjusted in response to nutrition - at start of a diet, the basal metabolic rate fails - to prevent using weight - restricted food intake does promote longevity, up to 40% in rats - in people probably not

SEX AND ESTROGEN

- estrogen rise before OVULATION promote nonhuman sexual behavior - if a female is SEXUALLY RECEPTIVE she is in estrus (dogs) // estrus is the period during which female animals are sexually receptive - women don't have estrus: - but are more likely to initiate sex as ovulation - monthly cycle is a cycle of hormones - androgens are necessary for male copulation - this does apply to human males - testosterone is linked to aggression and sex

LEPTIN

- fat cells produce leptin and secrete it into the blood stream - defects in leptin production or sensitivity give a FALSE LOW REPORT OF BODY FAT, causing animals to overeat - obese people are leptin resistant - over nutrition INFLAMES the hypothalamus - obesity, diabetes and heart disease 1.) adipose tissue, weight loss, leptin level falls: - Hypothalamus: food intake up, temperature down, energy expenditure down, reproductive function down, parasympathetic activity up 2. adipose tissue, weight gain, leptin level rises: - Hypothalamus: food intake down, energy expenditure up, sympathetic activity up

SOMATOSENSORY SYSTEM DETECTS TOUCH AND PAIN

- four touch receptor classes: - pain - touch - vibration -stretch

FIVE TOUCH RECEPTORS

- free nerve endings: - pain, temperature - in the outer layer of skin because they're useful to keep us safe from danger - Merkel's disc: - touch - kinda important - Meissner's corpuscle: - touch - kinda important - Pacinian corpuscle: - vibration - least important - Ruffini's ending: - stretch - least important

STRESS LEADS TO BRAIN CHANGES AND DAMAGE

- frontal cortex and hippocampal volume is REDUCED in combat veterans with PTSD and in victims of childhood abuse - cortisol tissue is reduced in torture victims - damage due to stress is caused by CORTISOL - perhaps increased receptor SENSITIVITY

PAIN CAN BE BLOCKED IN SPINAL CORD

- gate control theory of pain - fate can be closed by increased activity in A fibers: - A beta fibers produce touch sensation or nonpainful stimulus: - ex: if you hit your thumb with a hammer and then right after you squeeze the thumb to make it feel better - C fiber painful stimulus - other (descending) factors influence that gate: - attention - emotional/ cognitive factors

BOYS AND GIRLS ARE DIFFERENT

- gender is a continuum, not a dichotomy - girliness ------- boyness - girls talk alot, boys minimal - girls face to face conversation style, boys should to shoulder - girls relationships conversation content, boys objects and activities - girls nurturing touching, boys rough - girls loveable, loved power words, boys fair, loyal, honorable, respect - girls shared confidences badges of friendships, boys shared activities - girls release, signal for support crying, boys weakness and humiliation - girls cortex, more complex, with language process feelings, boys limbic system and less complex - girls think risky behavior is scary, stupid, lowers status among girls, boys think its fun, increases status among other boys - girls cortex dominates sexual arousal, boys limbic system dominates - girls considered veiled threat teasing, boys playful way to connect - girls afflictive "how would you feel" discipline, boys clear rules, consequences - girls fiction, relationships reading, boys facts, real stuff, action

UNEXPECTED SURPRISES ARE THE BEST

- give flowers on valentines day: 2 points - give flowers on a random day: 10 points - forget flowers: fail

AUDITORY NEURONS HAVE TONOTOPIC ORGANIZATION

- high pitch sounds in the back - high inside - low in front

SENSATION: SENSORY PROCESSING, TOUCH AND PAIN - CASE: IAN - at 19, ian became sick with a virus. His speech become slurred and a few days later he could neither walk nor sit - the man who lost his body: progressed until he could not control his own body movement because he could not feel his limbs at all. If he did not look at them, he could not tell where his arms or legs were, If the lights were out, he could not move purposefully. - he lost the ability to feel but not the ability to feel pain - why?

- his dorsal column - medial leminiscal pathway is messed up

SEXUAL ORIENTATION: GENETIC INFLUENCE

- homosexuality is 2-7 times higher among siblings of homosexuals than in general population - the more older BROTHERS a man has from the same mother, the greater the probability he will be homosexual, this is NOT TRUE FOR FEMALES - hormonal influence: - male homosexuals and heterosexuals have THE SAME testosterone levels - any hormonal influence on male homosexuality likely occurs PRENATALLY

NEURAL AND HORMONAL COMMUNICATIONS DIFFER

- hormones act in a gradual fashion - hormones often have pulsatile secretion (in bursts) - hormones are created in bursts, not one by one - some hormones are controlled by circadian clocks - body produces some hormones in the morning and some at night (ex: at night we produce melatonin)

endocrine feed back loop - understand how and why the feedback loop works - anterior pituitary

- hypothalamus connected to a part of the brain cell anterior pituitary part of the brain that secretes hormones // the ANTERIOR PITUITARY consists of many different endocrine cells, each secreting a different peptide hormone, this part synthesizes the hormones it releases - hormones are released into the blood stream and sent to the thyroid gland that produces thyroid hormones that are sent to target cells // the tropic hormone travels throughout the blood stream reaching all glands BUT only the TARGET glands have the appropriate receptors to respond to it - if some stress occurs than the system dumps a lot of thyroid hormones - negative feedback loop: controls how much or how little will be sent to target cells, sometimes we need more or less hormones // sometimes negative feedback is simple, the biological response is detected by the brain, which halts further hormone release.... for the anterior pituitary, hormones from the endocrine gland have a negative feedback effect on both the hypothalamus and pituitary - TROPIC (meaning directed towards) HORMONES: pituitary hormones that affect OTHER endocrine glands // anterior pituitary hormones that are directed towards different endocrine glands. - RELEASING HORMONES: from hypothalamus control pituitary release of tropic hormones // produced by the hypothalamic pituitary portal system to control the pituitary release of tropic hormones // the rate at which releasing hormones arrive at the anterior pituitary controls the rate at which the anterior pituitary cells release their tropic hormones into the general circulation -// NEGATIVE FEEDBACK: output of the hormone feeds back to inhibit the drive for more of that same hormone

ACUTE STRESS - epinephrine and norepinephrine - cortisol - immune system affected how?

- hypothalamus/ pituitary stimulate adrenals to release: - EPINEPHRINE AND NOREPINEPHRINE: increase output from the heart and liberate glucose - CORTISOL: provides sustained release or energy to cope - immune system is BOOSTED by acute stress: stress hormones stimulate astrocytes to release fibroblast growth factor 2, which in turn leads to NEW NEURONS: - the brain makes more neurons before you are born but has the capacity to provide the brain room to produce a few more - tress raised in a sealed biosphere fall over before they mature - this "perfect growing environment" lacks wind, which provides stress so the trees grow strong enough to support themselves - acute stress is harmful if too high

CHARLES WHITMAN'S DIARY - diagnosis? - what was wrong with him?

- i imagine it appears that i brutally killed both of my loved ones. I was only trying to do a quick job though - if my life insurance policy is valid please pay off my debts... donate the rest anonymously to a mental health foundation - maybe research can prevent further tragedies of this type - lately i have been a victim of many unusual and irrational thoughts - i talked to a doctors once for two hours and tried to convey to him my fears and that i felt overcome by overwhelming violent impulses - after my death i wish that an autopsy would be performed to see if there is any visible physical disorder - so why? - autopsy of his brain revealed a TUMOR the size of a walnut, erupting from beneath the thalamus, impacting the hypothalamus, extending into the temporal lobe and COMPRESSING THE AMYGDALA

IMPORTANT BRAIN AREAS OF SEX

- important in MALES: - sexually dimorphic nucleus - located in MPOA (INH3) (medial per-optic area) - 2-3x larger in men - male sex activity related to its size - size depends on prenatal exposure to testosterone - important for FEMALES: - ventromedial hypothalamus - receptivity to male advances; "in the mood"

AGGRESSION - BULLIES FIND SADISM REWARDING

- in aggressive teens, areas of brain linked with feeling good - amygdala and striatum - becomes active then they watch pain inflicted in others

NEURAL BASIS OF EMOTIONS

- incompletely understood: - more difficult to study emotions - can't completely control emotions - multiple areas of brain act together in any given emotion - some areas, though, are prime importance - FMRI studies have been key to learn about emotions

SOCIAL/ PERSONALITY INFLUENCES HAVE PSYCHOLOGICAL BASIS

- introverts with HIV have higher virus titers than extroverts with HIV: - may be due to link between introversion and norepinephrine level; - NE levels are higher in introverts, NE blocks immune system - flu antibodies INCREASE MORE following vaccinations in subjects who had higher activity in the left hemisphere - associated with positive emotions - married adults have lower cortisol levels than never married or previously married people: - having a partner results in lower cortisol levels - married people live longer

VIRATION PERCEPTION

- it is motivated by the pacinian corpuscle: - very old evolutionary sensor - uses mechanical gated sodium channels - if something stretched the skin (back and forth meaning vibration) it makes the channels larger so sodium and slip in - the important thing is to get the sensation from the pacinian corpuscle to the spinal cord

TRAINED SHIFT OF AN AUDITORY CELL'S RECEPTIVE FIELD

- it is not set in stone, it can change and learn - it can bend a little, not a lot - you can rewire your brain based upon experience - the act of listening actively can improve your ability to listen - its like: - learning a new language - learning to listen to music - learning your baby's voice

OUT TWO HEMISPHERES PROCESS EMOTION DIFFERENTLY

- left side of the face controlled by right hemisphere, is more expressive than the right side of the face - why is the left side more expressive? - hemispheres differ in RECOGNITION of emotions in vocal messages - RIGHT HEMISPHERE: identifies EMOTIONAL TONE: - not process meaning, identifies emotional content - LEFT HEMISPHERE: interprets MEANING of the message - patients with right hemisphere damage from stroke are unbothered or euphoric, even if their arm or leg is paralyzed: - they don't understand sarcasm - people with damage to the left hemisphere express more anxiety and sadness

CASE: dr. livingstone's attack by a lion in africa

- livingstone was attacked by a lion and felt no pain - after he was safe and away from the lion and all the pain set in - must be more to pain than just pain perception

PAIN IS LIFE SAVING

- low levels of pain during everyday tasks tell us when a certain movement or prolonged posture is harmful - even during sleep, mild pain makes us toss and turn enough to prevent bedsores or skeletal strain

VARIOUS CYCLE OF NEUROGENIC CHRONIC PAIN

- mechanism of RSD - start 1. original injury initiates a pain impulse carried by sensory nerves to the central nervous system 2. the pain impulse in turn triggers an impulse in the sympathetic nervous system which returns to the original site of injury 3. the sympathetic impulse triggers the inflammatory response causing the vessels to spasm leading to swelling and increased pain 4. the pain triggers another response, establishing a cycle of pain and swelling

OTHER NON DRUG TREATMENTS FOR PAIN

- meditation/ prayer - acupuncture - massage -physical activity

FYI: BUDDHIST COPING STARTEGIES

- meditation: focusing in a relaxed way on one structured aspect of a situation - mindfulness: nonjudgmental awareness and acceptance of the present moment - loving kindness: being nonjudgemental, compassionate, kind to oneself and others - morality: practicing right speech, right action and right livelihood, and doing these things with good intention - impermanence: realizing nothing lasts forever

SAMPLE QUESTIONS - in the auditory pathway, between the superior olive and the medial geniculate nucleus, is the..... A. Cochlear nucleus B. tympanic membrane (ear drum) C. inferior colliculus D. thigamajig

- memorize the pathway C. inferior colliculus

SEXUAL RESPONSE CURVES

- men vs. women: 4 phases: 1. excitement phase (arousal) 2. in plateau, arousal levels off 3. orgasm 4. resolution, as arousal fails and body returns to normal - MALE ORGASM: predictable, one shot - WOMEN'S ORGASM: know your partner's curve

REACTIVE AND PROACTIVE AGGRESSION INVOLVED DIFFERENT BRAIN AREAS - proactive aggression

- murders (reactive aggressors) have lower activity in PREFRONTAL CORTEX: - less gray matter in prefrontal cortex occurs in antisocial personality disorder - behave recklessly, overreact to provocation, and are sexually promiscuous - considered road rage - PROACTIVE AGGRESSION: is associated with psychopathy. they have: - less autonomic response to stress - impaired amygdala function - consider the boston bombers

HEMOSTATIC SYSTEM use our behavior to keep things balanced

- negative feedback systems are the main homeostatic mechanisms. If desired set point is devaited from, compensatory action begins - "ill eat when imhungry, ill drink when im dry. if the moonshine done kill me, ill live till i die"

AUDITORY NERVES SYNAPSE IN THE COCHLEA

- on the basilar membrane there are receptor cells - hair cells: - 2 kinds - have similar but different purposes - the inner hair cell: - is bigger, has a bigger job - attached to the vibrating basilar membrane - inner hair cells vibrate with it - the tectorial membrane has no function but to act as a roof - the hair cells have stuck themselves into the tectorial membrane (which is rigid) - so the hair cells bend which trigger an action potential - will use glutamate as a neurotransmitter - release of glutamate will activate the action potential to the brain: - there is a descending impulse, in the opposite action - Ach - nerve fibers 1. Afferent, to cochlear nucleus of brainstem 2. Efferent, from lateral superior olivary nucleus 3. afferent, to cochlear nucleus 4. efferent, from medial superior olivary nucleus

OVEREATING CAUSES BRAIN DAMAGE - HYPOTHALAMIC SCARRING - MICROGLIA ACTIVATION

- overeating -> hypothalamic inflammation -> inhibits/ blocks neurogenesis, resets your set point: - you you were to rest your set point to even higher, that will make you eat more - high calorie diers cause HYPOTHALAMIC SCARRING and MICROGLIA ACTIVATION, and 15% reduction of pro opiomelanocortin (POMC) neurons, which normally activated by leptin to block eating and increase energy expenditure - but the brain can recover, if overeating stops: - newborn hypothalamic cells become NPY/ AgRP - and POMC neurons. These new neurons are responsive to fasting and leptin

PET IMAGING OF MALE ORGASM

- oxytocin releases at ejaculation; and maybe promoting bonding? - primary activation was in VENTRAL TEGMENTAL AREA: - activation of dopamine

THE MULTIFACETED CHARACTER OF PAIN

- pain is more than just an intense sensation - broken wrist - information sent to spinal chord: - three different arenas for the sensation to be felt: 1. cognitive system: as cameras go on the player bc he is out of the game now, the athlete repressed his emotional response to not cry 2. motivational affective system: appropriate motivation can suppress pain: - now that the game has been paused and you ask me does my wrist hurt then yeah i notice 3. sensory discriminative system: gives ability to describe what is wrong - sharp pain in left wrist - hurts more if i hold it down - characterizing the pain verbally summarized: Peripheral input (broken wrist) goes to spinal cord processing then to pain perception - pain perception: cognitive system, motivational affective system and sensory discriminative system this results in the motor response mechanism

TEMPERATURE RECEPTORS USE THE PATHWAY

- pain uses two type of neurons: - small unmyelinated (slow) C fibers: DULL pain: - large MYELINATED (fast) A delta fibers: SHARP pain - why have 2 different speeds? - C FIBERS: - small, unmyelinated slow C fibers carry signals from CMRI and TRPV1 receptors, signaling cool temperature or dull pain, respectively. - CMRI free nerve endings respond to LOW temp - TRPV1 free nerve endings respond to MODERATE heat - A DELTA FIBERS: - large, myelinated fast A delta fibers carry signals from TRP2 free nerve endings signaling sudden, sharp pain - TRP2 free nerve endings respond to high temperature

IMPAIRED FACIAL EXPRESSION LIMITS SOCIAL INTERACTIONS - CASE: moebius syndrom - CASE: bells palsy

- parkinson disease, schizophrenia, facial nerve paralysis - CASE: a girl has moebius syndrome. Her face is very neutral with no smile - how does she feel? happy. But she physically cannot smile like normal - why?: she has moebius syndrome which is a congenital absences of intervention of the facial nerves so her face is paralyzed preventing her from being able to move her cheeks to smile: - this can create a problem for her to socialize and make friends because her friends may not understand she simply cant smile - CASE: a women has bell's palsy: a facial paralysis on just one side: - can create social awkwardness because some people wont know how to react since we use the face to understand a person's emotions

CHORNIC PAIN ALSO REMODELS SENSORY CORTEX

- patients in chronic pain have OVERACTIVE SOMATOSENSORY cortex at rest

PHANTOM LIMB PAIN

- refers to ongoing painful sensations that seem to be coming from the part of the limb that is no longer there. The limb is gone, but the pain is real. the onset of this pain most often occurs soon after surgery

GHRELIN - case: Prader will syndrome

- released by stomach endocrine cells - appetite stimulant - rises during fasting, drops after eating - some obese people have elevated ghrelin. levels (not many just some) - CASE: for kate kane, food is on her mind "all the time". Kate, 26, have Prader will syndrome, a genetic disease that causes a sense of never being full or satisfied. Kane feels so hungry that she even eats out of the garbage to get to her food. Parents had to lock their refrigerator doos. She could eat until she died basically - why? the brain always says that she is super hungry

WHY DO WE HAVE SEX?

- reproduction (more of us) - DNA shuffling (but not exactly us) - its fun (uniquely human) - sex is like hunger and thirst: - it is not a homeostatic tissue need - individuals don't require sex for survival (species do)

GENDERS: BEHAVIORAL AND COGNITIVE DIFFERENCES

- some girl- boy differences firm: - most girls have greater verbal ability than most boys - most boys excel in visual spatial ability - most boys are more physically aggressive than girls - more boys are great at math than girls; but overall ability is the same: why? there are more boys than girls who are terrible at math - however, there is MOSTLY OVERLAP BETWEEN men and women - you can focus on the small differences or on the overall similarity

WHY IS THIS IMPORTANT? - to face our fears

- sometimes we have to face our fears the first time so we can stop being fearful of them after

AUDITORY PATHWAY OF OUR BRAIN

- sound comes into the ear at the cochlear - activates the inner hair cells which causes an action potential to occur in the auditory nerve - when they first enter the brain stem, they stop and make a connection in a very important part of the brain ( at the superior olive): - the superior olive is the first place the information is in the CNS - then it heads pass through the inferior colliculus and then into the auditory cortex: - 5 different stations

BASICS OF SOUND

- sound waves are distinguished by their amplitude, measured in decibels (dB) and frequency, measured in hertz (Hz) - 32 Hz sound will be higher pitch than 20 Hz - amplitude or intensity = loudness - frequency = pitch

TESTOSTERONE AND COGNITION

- spatial abilities are enhanced in androgenized girls - males LOW IN TESTOSTERONE in development are IMPAIRED IN SPATIAL ABILITY - testosterone improves spatial ability in older men - female to male transexuals taking testosterone show spatial improvement, but loss of verbal fluency

STRESS

- stress is a demanding condition in the environment, AND it is the individuals' internal response to that situation

HORMONAL RESPONSE TO SOCIAL STRESS

- stress level before a test are high and right after drop

STRESS ACTIVATES MANY BODY RESPONSES - hypothalamic control - adrenal cortex - adrenal medulla - cortisol

- stress response activated the sympathetic nervous system, VIA HYPOTHALAMIC CONTROL - resulting increased heart rate, blood flow and respiration rate help the person deal with the situation - ADRENAL CORTEX: secretes CORTISOL - ADRENAL MEDULLA: releases EPINEPHRINE AND NOREPINEPHRINE - how do we release cortisol? - hypothalamus pituitary releases some ACTH and floats around till it gets to the adrenal gland located above the kidney - the adrenal gland under the influence of cortisol is going to make epinephrine and norepinephrine which seeps into the blood stream where some will flow back into the brain and there is a negative feedback loop and inhibits its own production - CORTISOL: is a stress hormone that increases blood glucose and breaks down protein

EACH PASRT OF THE EAR HAS A FUNCTION

- the EXTERNAL EAR and ear canal collects low frequency sound waves - three TINY BONES: MALLEUS, INCUS AND STAPES - connect tympanic membrane (ear drum) to OVAL WINDOW - vibrating air (noise) makes the skin vibrate and vibrating skin makes the bones vibrate: - why so many steps? - oval window is the window to the COCHLEA - two muscles in middle ear vary lineage of ossicles: - tensor tympani, stapedius - when activated too much, MUSCLES STIFFEN to dampen loud sounds: - the body is trying to protect the ear drum from noises too loud and intense (ex: like at a concert) - the sound wave energy is transferred to the three bones of the middle ear, which vibrate - the cochlea unrolled: - vibrating fluid makes the basilar membrane vibrates

FOR LOW FREQUENCY SOUNDS, LOCATION IS CODED BY LATENCY DIFFERENCES IN SUPERIOR OLIVE

- the MSO computes the location of low F (<3kHz) sound by intramural time difference - there is a loud speaker - the ear can hear it and the superior olive makes latency connections - the sound comes from the left - the left ear gets a head start - goes into the entire medial superior olive - right ear measures latency which is different in each ear because the right ear is farther away from the sound - coincidence detector: - which MSO neuron will fire?: - you need two impulses from the left and right ear to give a strong enough impulse and EPSP to make the neurons fire - E will fire - Time difference - Medial SO Medial SO compares Meeting times COINCIDENCE DETECTION - sounds from the left will be heard by the left ear before the right: vice versa - is the sound comes from straight ahead, it will reach the ears at the same time

LEVELS OF TOUCH PROCESSING

- the face and body are touched (have same sensory receptors) - send into to spinal cord up to brain stem - then to the thalamus a connection is made - to the primary sensory cortical areas - then spread to anterior and posterior non primary sensory cortical areas - most sensory pathways pass through the thalamus to end in cerebral cortex

FOR HIGH FREQUENCY SOUNDS, LOCATION IS CODED BY INTENSITY DIFFERENCES IN SUPERIOR OLIVE

- the lateral superior olive will do the same spatial localization but with intensity (loudness) differences not meeting times - lateral superior olive encodes sound location of high f (>3kHz) sound through interarual intensity differences

EMPATHY: I FELL WHAT YOU'RE FEELING

- the touch cortex lights up if you've been touched - somatic sensory cortex lights up when you see someone else being touch, you feel their touch or their pain

HYPOTHALAMUS IS THE HUNGER CONTROL CENTER - THERMOSTAT

- their job is to take in all the incoming signals and says to you if you are hungry or not hungry - LATERAL HYPOTHALAMUS (LH) lesions: refusal to eat - VENTROMEDIAL HYPOTHALAMUS (VMH) lesions cause obesity - VMH lesioned animals OVEREAT until they become obese: - increase weight stabilizes - this weight is maintained even after food manipulations - LH lesioned animals STOP EATING, but resume and stabilize their weight at a new, lower level

SYNESTHESIA - CASE

- this woman had a small stroke in right somatosensory thalamus; later, certain sounds induce intense unpleasant tingling in her left hand and arm - can you see what must have happened?: - overlap of auditory and touch cortex - decreased response to touch; increased response to sound

CASE - ISRAEL KAWMAKAWIWO'OLE - IZZY

- throughout his later life, Izzy was obese, at one point carrying 757 pounds. At age 38, he died of heart failure at medical center in Honolulu in 1997 - hawaii's state flag flew at hald staff on the day os his funeral, and his body lay in state at the capitol in honolulu, the only private citizen ever to be so honored

TOUCH RECEPTIVE FIELDS

- touch far away - no effect - touch in SURROUND - DECREASED firing - touch in CENTER - MAXIMAL firing - on center, off surround

PAIN IS BLOCKED BY GATING IN SPINAL CORD

- transcutaneous electrical nerve stimulation (TENS) delivers electrical pulses to the skin

HYPOVELEMIC THIRST - BARORECEPTORS - HYPOVOLEMIA

- triggered by LOSS OF WATER VOLUME: concentration is not changed - BARORECEPTORS: in blood vessels and heart detect the initial drop - brain activated thirst and salt craving - arteries constrict to raise Bp - HYPOVOLEMIA: causes release of vasopressin (antidiuretic hormone): - induces blood vessel constriction and so reduces blood flow to the bladder - FYI: on DIABETES INSIPIDUS: vasopressin is not produced - kidneys send more urine to the bladder, resulting in chronic thirst

AGGRESION IN PEOPLE

- tumors in amygdala, hypothalamus or septal area can cause aggression - seizure activity in the amygdala increases aggression - murders have higher activity of the amygdala and hypothalamus - removing the amygdala reduces aggression in 33-100% of patients - CASE: - 13 year old boy made multiple suicide attempts, tried to ride his skateboard on the freeway, and attempted violent acts against others, ranging from impulsive physical abuse of other children to an attempt to drop a brick on the head of an adult. He was places in restraints up to 6 hours per day

POSTERIOR PITUITARY SECRETES TWO HORMONES - VASOPRESSIN - OXYTOCIN

- vasopressin: ((antidiuretic hormone (ADH)) raises blood pressure and inhibits urine formation - keeps you alive - controls thirst // for thirst and water regulation, promotes water conservation and increases blood pressure - oxytocin: maternal behavior/ bonding. Autism? - maternal bonding is impaired in autism // involved in reproductive and parental behavior, triggers milk letdown in the nursing female and is also associated with a variety of complex behaviors

CASE - KULESHA - an infant's fam resettled to america in febuary 2004, in march 2004 the mother was found to be pregnant - on nov 4th, she gave birth to a girl weighing 5 pounds. the infant girl was noted to have a left eye cataract. Newborn otoacoustic emission test found severe bilateral hearing loss - development since has been delayed - small head - microcephaly: neurogenesis disturbed - why was Kulesha deaf and ended up dying?

- viral infections such as measles and CMV kill developing auditory hair cells

SAMPLE QUESTION - which brain structure is involved in sexual orientation? a. medial preoptic area b. anterior commissure c. ventral tegmental area d. ventromedial hypothalamus

- we actually don't know, in different sexual orientation there are different sized anatomical part of the brain

HUMAN HEARING

- we can hear about 20 Hz to 20,000 Hz - human speech evolved to match where human hearing is best or human hearing evolved to match where human speech would be heard best

GASTRIC BYPASS SURGERY - what is it? - reduces and increases what?

- weight loss averages 25% and is long lasting (compared to 5% to 10% with dieting and relapse within a year) - surgical creation of a tiny stomach - reduces GHRELIN and increase PYY and GLP-1 reducing hunger - reduces mortality and has many health benefits

BRAIN DEVELOPMENT: SEX DIFFERENCES - connectivity

- women are better at multitasking - men are better at concentrating on one task - men are better connected front to back - women are better connected left to right

EATING DISORDERS OCCUR WITH OTHER PSYCHIATRIC CONDITIONS - stats - larger insula larger orbiofrontal cortex

- women with anorexia or bulimia: - 40% childhood anxiety disorders - 20% obsessive compulsive disorder - 30% abuse alcohol or drugs - 90% depression - 0f 246 women with an eating disorder: - 30% attempted suicide - 5% died - teenage girls with anorexia have: - LARGER INSULA: area active when you experience disgust - LARGER ORBIOFRONTAL CORTEX: area that tells you ' you shouldn't do that'

OBESITY AND REDUCED METABOLISM - BMR

- your body defends itself when you go on a diet: - when you restrict food it changes your BMR - BASAL MEATBOLIC RATE (BMR): - energy required to fuel the brain/ body and maintain temperature - 75% of energy expenditure in average sedentary student - women on a diet, the 1/3 who failed to lose weight had LOW BMRs - heredity accounts for 40% of a person's BMR. BUT ACTIVITY CAN INCREASE IT

YOUR BRAIN AND YOUR SEXUAL ORIENTATION

1. (Bed nucleus of the stria terminalis) 2. sexually dimorphic nucleus (INH3) 3. suprachiasmatic nucleus

HOW DO WE HEAR PITCH (FREQUENCY) TWO WAYS

1. FREQUENCY CODING: firing rate of auditory neurons encodes pitch: 50 Hz sound causes an auditory cell to fire 50 times a sec - come cells fire at different frequencies: - when there is an action and it has reached its peak the cell fires - How about higher pitches?: - Volley principle: frequency of the sound waves (on top) is TOO HIGH for any single fiber to fire EVERY CYCLE - so, each fiber only fires at a certain point in the cycle though it does not respond to each cycle

PLACE AND VOLLEY MECHANISMS ACT TOGETHER TO CODE FREQUENCY

1. LOW FREQUENCIES: are coded by FREQUENCY of nerve impulses (up to 1000 Hz) - FREQUENCY CODING 2. HIGH FREQUENCIES: are coded in terms of the PLACE along the basilar membrane which shows greatest activity (over 5000 Hz) PLACE CODING 3. for INTERMEDIATE FREQUENCIES (1000 to 5000 Hz) pitch is coded through BOTH volley and place mechanisms - this is where speech is

TWO SETS OF NEURONS IN HYPOTHALAMUS HAVE OPPOSITE EFFECTS

1. NPY / AgRp neurons: produce neuropeptide Y and agouti- related peptide: - STIMULATE appetite and LOWER metabolism -> weight gain 2. POMC/ CART neurons produce pro- opiomelanocortin and cocaine - and amphetamine related transcipt (CART): - INHIBIT appetitie and RAISE metabolism -> weight loss - VMH lesions destroy anorexigenic PVN - LH lesions destroy anorexigenic PVN - LH lesions destroy orexigenic PVN - LH lesions destroy orexigenic LHA - leptin inhibits AgRp neurons and stimulates POMC neurons

HORMONES OF THE ANTERIOR PITUITARY GLAND - what are the three steps

1. hypothalamic neurons synthesize releasing hormones 2. releasing hormones are then secreted into local blood vessels 3. releasing hormones float to anterior pituitary, which releases hormones and regulate endocrine glands throughout the body

SOUND BENDS THE STEREOCILLA ON AUDITORY HAIR CELLS

1. vibration makes stereocilla bend, causing ion channels to open 2. the hair cell depolarizes, and calcium influx at the base of the cell causes glutamate release - hair cells do not have axons so therefore do not generate action potentials

HOW WE HEAR PITCH? (SECOND IDEA)

2. PLACE CODING: each place on basilar membrane has a resonate frequency A. the membrane is caused to vibrate by the fluid that surrounds it therefore in the environment if we place a 100 Hz noise then we look at the membrane the membrane will vibrate at a different point B. the membrane is shaped like a cone: - thin in the front and thicker in the back - high pitch will cause the front of the membrane to vibrate - low pitch will cause the back of the membrane to vibrate - just like tuning a guitar: - the diameter of the guitar sting determines its frequency (pitch)

SAMPLE QUESTION - lets say your mother has a high serum thyroid level from taking too many thyroid pills. Expect her TSH to be: A. low B. High C. in the middle

A. low - High TSH levels can mean your thyroid is not making enough thyroid hormones, a condition called hypothyroidism. - Low TSH levels can mean your thyroid is making too much of the hormones, a condition called hyperthyroidism.

Case - C.V. is a 3 month old boy with severe constipation since birth cannot hold his head up, and he does not smile. His head is small - his temp in the nursery at birth was 96.1 - he was unable to control his body temp - unable to smile or hold up his head - the problem must be predated from before birth - why?

He has a hormone deficiency

FACIAL FEEDBACK IN EMOTION

Posed expressions produce the intended emotion, and the associated physiological arousal; SO WE CREATE OUR OWN EMOTION - use this to your advantage; you can't think your way into a new behavior, but you can tact yourself into a new way of thinking: - meaning you could smile and make yourself feel a bit better - the most common psychotherapy for depression

quiz ? chomsky and pinker have advocated a language acquisition device, which is

a part of the brain dedicated to learning and controlling language

SAMPLE QUESTION - your crazy dermatologist injects histamine into the skin of your left arm. this hurts because... a. free nerve endings stimulates b. histamine activated cells in dorsal column pathway - pain is the spiral pathway - touch is in the dorsal column pathway c. histamine causes merkel and meissner cells to fire - these are for touch not pain d. none of the above

a. free nerve endings are stimulated

SAMPLE QUESTIONS - dumbo has big ears so he can hear a. low frequency sounds b. high frequency sounds c. modest mouse d. the sound of one hand clapping in a forest

a. low frequency sounds

SAMPLE QUESTION - the dull, long lasting pain in toe when you hit it against the bed post in your dark room is due to the activation of a. small unmyelinated C fibers - small unmyelinated A delta fibers - large myelinated A delta fibers - large myelinated C fibers

a. small unmyelinated C fibers! c. would be rapid intense pain

SAMPLE QUESTION - your gonadal sex is determined by whether you have? A. testes B. y chromosome - genetic sex b. x chromosome - genetic sex d. dallas cowboy tickets

a. testes - why? A gonad, sex gland, or reproductive gland is a mixed gland that produces the gametes (sex cells) and sex hormones of an organism.

SAMPLE QUESTION - blood signals that stimulate appetite include - rising ghrelin - rising cortisol - falling insulin - all of the above

all of the above

SAMPLE QUESTION - which brain structure is larger in gay men than in straight men? a. medial preoptic area b. anterior commissure c. INAH3 d. ventromedial hypothalamus

b. anterior commissure

SAMPLE QUESTION - women have bigger ______ than men a. INAH3 (sexually dimorphic nucelus) b. corpus callosum c. cerebellum d. brain

b. corpus callosum

SAMPLE QUESTION - what surgical treatment would best help a patient with RSD? a. cutting the peripheral nerve from the injured area b. cutting the sympathetic nerve to the injured area c. cutting the spinal cord about the site of injury

b. cutting sympathetic nerve to the injured area why? because sympathetic nerve drives the pain cycle c. would leave them with no pain, but also leave them paralyzed

SAMPLE QUESTION - right hemisphere identifies ____ and the left hemisphere interprets ___ of the message a. meaning, emotional tone b. emotional tone, meaning c. i give up

b. emotional tone, meaning

SAMPLE QUESTION - the major part of the pain pathway that contributes emotion to pain sensation is.... a. periaqueductal gray b. spinothalamic tract c. somatosensory cortex d. cingulate gyrus

d. cingulate gyrus

SAMPLE QUESTION - the insula is more important in.... a. fear b. contempt c. impulsiveness d. empathy

d. empathy

SEX DETERMINATION

developmental event that decides if embryo will be male/female gonadally - SRY gene - sex determining region on Y chromosome - is responsible for development of testes - without an SRY gene, an ovary forms

quiz ? in contrast to chronic stress, short term stress...

enhances the immune response

quiz ? damage to the right hemisphere

impairs an individuals emotional response

quiz ? vicious cycle of neurogenic chronic pain is maintained by overactivity of the

inhibitory spinal neurons

quiz? activity of the periaqueductal gray nucleus of the brain stem

inhibits pain signals from entering the brain

quiz ? steve was basement cleaning and found a recently deceased rat; his revulsion intensified as steve forced himself to pick it up. what brain areas mediated his disgust?

insula and basal ganglia