Exam 2 Part 2

cingulate cyrus

empathy and pain processing

Far away touch

no effect on action potential firing

Glycogensis

converting glucose to glycogen, using pancreas hormone insulin

aggression

Behavior intended to harm Two types: reactive and proactive Reactive - impulsive, emotional, provoked Proactive - emotionless, unprovoked Areas of brain in aggression: amygdala, hypothalamus, and septal area Murderers have higher activity in amygdala and hypothalamus

Chronic Stress

Causes issues with memory, appetite, sexual desire and performance. - Reduces energy and disrupts mood. - Unlike acute stress, it actually compromises the immune system. This is because the hormones released in chronic stress, suppress the immune system. - Increase in body inflammation.

locus coeruleus

known to secrete Norepinephrine. Responsible for emotional arousal, depression, pleasure, and stress.

ventromedial hypothalamus

lesions cause obesity

lateral hypothalamus

lesions will lead to the refusal of eating

Center receptive field

more firing of action potentials

Gluccorticoid Hormone

most common one is Cortisol

NYP/AgRP neurons

produce neuropeptide Y and agouti-related peptide: they stimulate appetite and lower metabolism (weight gain

POMC/CART nerouns

produce pro-opiomelanocortin and CART: inhibit appetite and raise metabolism (weight loss)

Cortisol

provides energy for the body to cope with the situation

Proactive agression

psychopathy, sociopathy ○ Impaired amygdala function and less autonomic response to stress

Murders

reactive aggressors have lower prefrontal cortex activity. ○ Less gray matter in PFC - antisocial personality disorder

Hypothalamus

responsible for Autonomic Nervous System reactions

Amygdala

responsible for aggression, emotional memory, and fear

Hippocampus

responsible for memory (different from emotional memory

adrenal medulla

secretes Epinephrine/Norepinephrine

tonic receptors

slow or no decline in AP frequency

Congential sensivity to pain

unable to perceive pain, mutated sodium channel in pain fibers in dorsal root ganglia

Lipids

for long-term storage, are fat tissue

adrenal cortex

secretes Cortisol (important stress hormone, that increase blood glucose + protein breakdown)

orbitofrontal cortex

Its' role is to inhibit any raw emotions from the amygdala - Prefrontal cortex split into Dorsolateral, and Orbitofrontal cortex.

prefrontal/orbitofrontal cortex

Makes decision before an action is taken. - Applies moral rules/values to daily functioning - Abnormalities here lead to an increase in aggression, depression, and Schizophrenia.

left hemisphere

Active in positive emotions.

Love

Right Caudate, VTA

Disgust

insula

Osmotic thirst

Is stimulated by high extracellular solute concentrated

Lust

Septal Area

Surrounding Receptive Field

decreased in firing of action potentials

Man on fire syndrome

- congenital hypersensitivity to pain, severe pain sensation triggered by an increase in temperature, heat, stress.

Epinephrine/Norepinephrine

: increase blood glucose and increase output from heart

synthesisa

A stimulus in one modality creates a sensation in another "This food tastes blue" LSD or posterior temporal lobe seizures can cause this problem

Stress

Activates the sympathetic nervous system (fight/flight response) - It is regulated/controlled by the hypothalamus - Effects on the body include increased heart rate, breathing rate, and blood flow - Adrenal Gland plays important role:

Fundamentals of sensory system

All sensory processing begins in receptor cells ● A stimulus produces graded potentials which can lead to action potentials ● Intensity of a stimulus can be coded ○ Changes in frequency of AP's can convey stimulus in a single neuron ○ Multiple neurons can act in parallel with more neurons actings in conjunction with a stronger stimulus ○ Range fractionation - different neurons respond to a specific range of stimuli

PTSD Brain changes

Amongst patients with PTSD, there is reduced frontal cortical and hippocampal volume ● In tortured victims, there is reduced cortical tissue ● Stress-induced brain damage is due to cortisol, possibly as a result of greater receptor sensitivity ○ Generally, PTSD patients have low serum cortisol while depressed patients have high serum cortisol. This does not necessarily hold true in all cases

Brain Control of Drinking

Circulating angiotensin II acts in the subfornical organ (SFO) to signal other brain sites to initiating drinking

Obesity treatment

Eat less/exercise: Combining those 2 together really helps Exercise (200 minutes per week) 2) Gastric bypass surgery (surgical creation of a tiny stomach) : reduces ghrelin and increases PYY and GLP-1, reducing hunger Reduces mortality and has many health benefits

Diets dont work

Energy expenditure is adjusted in response to nutrition At the beginning of a diet, the basal metabolic rate falls-to prevent losing weight Restricted food intake does promote longevity

Hunger Hormones

Fat cells produce leptin and secrete it into the bloodstream Defects in leptin production or sensitivity give a false low report of body fat, causing animals to overeat Obese people are leptin-resistant Overnutrition inflames the hypothalamus- obesity, diabetes, and heart disease

Homeostatic Controls

Homeostatic systems use our behavior to keep things balanced Negative feedback systems are the main homeostatic mechanisms if a desired set point is deviated from, compensatory action begins

Social Influence Hypothesis

Homesexual thoughts and actions stem from environmental factors, such as through early seduction

biological hypothesis

Homosexuality is has biological origins. As a result, non-conformity is felt during early childhood (As early as ages 4-5) ○ Genetic origins can explain the 2-7 times increased detected homosexuality among siblings than the general population ○ Note: Both homosexual and heterosexual men have the same testosterone levels, meaning that hormonal influence is more likely to occur prenatally (before birth

Antigotensin Cascade

If blood volume decreases, kidneys release renin, which triggers formation of angiotensin II

Socialbility

Introverts with HIV are shown to have higher virus titers (concentration) than extroverts with HIV. This can be explained by an elevated level of norepinephrine in introverts, which suppresses the immune system ● Flu antibodies increase more following vaccinations in subjects who had higher activity in the left hemisphere, which is associated with positive emotions

Behavorial and Cognitive differences across genders

Most girls have better verbal ability than boys ● Most boys have better visual-spatial ability than girls ● Boys are more physically aggressive ● More boys are better at math but the overall ability is the same ● Note: Gender is a continuum, not a dichotomy. Many of these differences are extremes are there is mostly overlap between the abilities in girls and boy

Laughter

Orbitofrontal cortex

Osmotic Thirst Mechanisms

Osmosensory neurons in anterior hypothalamus (OVLT) respond to rise in blood osmotic pressure Their cell membranes shrink, opening mechanical-gated Na+ channels OVLT neurons respond to increased osmotic pressure by causing the pituitary to release antidiuretic hormone (ADH)

Chronic long lasting pain

Pain that persists long after injury and healing Pain signals remain active for many months or years Examples are neurogenic pain (nerve damage) and psychogenic pain (psychological pain, non visible damage

Four touch receptor classes

Pain ● Touch ● Vibration ● stretch

Bulimia

Recurrent binge eating Recurrent inappropriate compensatory behavior at least 2X a week for 3 months

anroexia nervosa

Refusal to maintain body weight - Fear of weight gain - Body image disturbance - Amenorrhea - Restricting or binge-eating/purging type Anorexia nervosa has the highest mortality rate of any psychiatric disorder Teenage girls with anorexia have Larger Insula: area active when you experience disgust Larger orbitofrontal cortex- area that tells you "you shouldnt do that

Ghrelin

Released by stomach endocrine cells- Appetite stimulant Rises during fasting; drops after eating Some obese people have elevated ghrelin levels

Receptive field

Sensory neuron responds to a specific stimulus. Each sensory neuron has its receptive field. Each receptive field is in different size and shape.

Gate control theory of pain

Spinal cord can block pain Increase in A fibers can close gate

ventral tegmental area

Substantia Nigra: known to secrete Dopamine. Responsible for the feeling of exhilaration/excitement.

Pain and tempature

Temperature receptors use the pain pathway Pain pathways involve two types of neurons ● Small, slow, unbeyinated c fibers, dull pain ● Large myelinated, fast A delta fibers, sharp pain

Sensory integration disorder

The brain has trouble integrating senses ● Hypersensitivity to touch - stimulus avoiders ○ Refuses to walk barefoot or have distress when washing hands or face ● Hyposensitivity to touch - stimulus seekers ○ May pinch or bite themselves

Hommoculus and Somatosensory cortex

This part of the brain is divided based on different body parts Cortical map - areas in the brain that are identified in performing specific tasks The somatosensory cortex can reorganize itself when one part of the body isn't used anymore (ex. arm amputation)

spinothalamic system

Transmits pain and temperature Periaqueductal gray- in the midbrain, involved in pain perception and usage of opioid receptors

Hypolvolmeic thirst mechanism

Triggered by loss of water volume- concentration is not changed Baroreceptors in blood vessels and heart detect the initial drop Brain activates 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: in diabetes insipidus vasopressin is not produced-kidneys send more urine to the bladder - This results in chronic thirst

phasaic receptors

adapt quickly by decreased frequency

Left frontal lobe

behavior approach. Emotions regulated: anger & joy.

Right frontal lobe

behavior withdrawal. Emotions regulated: fear & sadness. Active in negative emotions

Kluver-Bucy syndrome

increased aggression in 6 year old boy, behavior alternated between apathy and hyperactivity.

ATCH

is a hormone that is released by the anterior pituitary gland.

PTSD

is developed due to experiencing a stressful event that may have been threatening or catastrophic in nature. - Common symptoms include: flashbacks of re-experiencing the event, avoiding certain people or places that trigger memories, and hyperarousal symptoms such as panic. - Treatments: may include desensitization, propranolol (a beta blocker, essentially an anxiolytic drug), MDMA/Ectasy assisted therapy has shown promising results in trials (however there is a high chance for substance abuse)

Gloycgen

is glucose stored for short term in the liver

hypovolemic thirst

is stimulated by low extracellular/intravascular volume

Glucose

is the principal fuel for energy