Exam3 Central Nervous System

Which gender has a larger decrease in brain volume and lose more neurons in old age?

Males. Males show larger decrease in brain volume due to hormones.

What's another name for membrane potential?

Membrane voltage

Synaptic Vesicles

Membrane-bound organelles that hold neurotransmitters

Dendrites

Much shorter projections and receive signals from other neurons

What disease indicates malfunctioning oligodendrocytes because areas of their nervous system do not have uniform myelin (a depleted myelin collection)?

Multiple Sclerosis (MS)

True or False: Axons are located in the innermost core of the spinal cord.

True.

True or False: Each segment of the spinal cord contains 2 spinal nerves that flank the spinal cord.

True.

True or False: Males have higher functioning PARIETAL LOBES and perform better on mental rotation tests

True.

True or False: Neurons have different functions.

True.

True or False: Neurons vary in shape and size.

True.

True or False: Plaques and tangles appear in predictable patterns in the brains of Alzheimer's patients.

True.

True or False: Short term memories can be transferred to long term.

True.

True or False: Spinal nerves contain sensory neurons.

True.

True or False: The Cerebral Commissure is much more developed in females

True.

True or False: The action potential is a voltage that moves.

True.

Ture or False: The mor eyou do something, the greater the connections.

True.

What is the opposite side of the dorsal side?

Ventral side.

When does the Action Potential occur?

When the RMP reaches a certain electrical threshold

When does the RPM fluctuate?

When you sample to nerve cell body; It becomes more negative or more positive depending on the chemicals (neurotransmitters- some neg. some pos.) released at that site

Why is CSF neccessary?

Without it the weight of the brain would collapse upon itself

How do you transfer short term memories to long term?

You associate things you don't know with things you do know which strengthens the connections of an old network and provides another route for your brain to access the info

How does even one or two drinks (only a little alcohol) affect your memory?

Your LDP can be impaired

Describe the characteristics of the FRONTAL LOBE of the cerebral cortex.

-"Higher functions" -JUDGEMENT/ INTELLIGENCE -Recognizes future consequences of actions -know diff btw good & bad OR good & better -overrides or suppresses unacceptable social responses -compares and contrasts -ALCOHOL inhibits the abilities of the frontal lobe and can lead you to do inapproriate or risky behaviors

Describe the characteristics of the BRAIN STEM.

-"lower brain" -LIFE SUPPORT SYSTEM of the CNS -regulates: breathing, heart rate, blood pressure -the lower extension of the brain connects it to the spinal cord -pathway for nerves traveling to the highest oarts if the brain

What is the Resting Membrane Potential (RMP)?

-60 membrane potential (mp); this means that the inside of the neuron is minus relative to the outside

Describe the characteristics of the TEMPORAL LOBE of the cerebral cortex.

-AUDITORY perception -also houses the HIPPOCAMPUS (long term memory)

What factors influence your risk for having a "blackout"?

-Blood Alcohol Level (BAC) -the rate of consumption -prior history with blackouts (if you've had them before you're more susceptible to future ones) -gender (females more susceptible)

What is the function of the MEDULLA?

-CONTROLS the body's AUTONOMIC funtions (respiration, digestion, heart rate) (swallowing, coughing, vommitting) -relay station for nerve signals going to and from the brain

What is the cause of RMP and AP?

-IONS determine all the electrical events in neurons -depeneding on the ION and the concentration on either side of the neuronal membrane, the inside will be either postive or negative Therefore, all cells in your body have an electrical potential due to the difference of concentration of IONS

Describe the elements of memory.

-Storage, rentention, and recall of info including past experiences, knowledge, and thoughts -most memories are reconstructions -in order to recall a memory we must reconstruct it frm elements scattered throughout various areas of our brains

Define LONG-TERM MEMORY.

-ability to store info for months to years -facts, semantics, & autobiographical info -organized so that its easy to reach a stored item by MANY routes EXAMPLE: you can find word "cookie" by thinking of "grandma" or "milk" or "Choc chip" -Mostly stored in the FRONTAL CORTEX -HOWEVER, visual info about the cookies could be stored in the temporal cortex, etc.

Define SHORT-TERM MEMORY.

-ability to store info for seconds to minutes -limited capacity (usually 3-4 itmes) EXAMPLE: remembering a phone # until dialed (working memory- holding info long enough to carry out actions) -new info "bumps" othr info out of shorterm mem -found in HIPPOCAMPUS and SUBICULUM

Describe the characteristics of a STROKE.

-caused memory loss -is cuased by a sudden loss of blood flow to the brain (ISCHEMIC STROKE) OR by a bleeding inside the head

Describe the characteristics of the CEREBELLUM.

-controls BALANCE and fine motor movements -learns and remembers motor responses (msucle memory) -hand-eye coordination, musical and artistic abilities

What is the function of the MIDBRAIN?

-initially integrates sensory input and projects it to region in the cerebrum EXAMPLE: hear a loud noise and respond

Describe the characteristics of the PARIETAL LOBE of the cerebral cortex.

-integrates sensory info frm diff parts of the body -knowledge of numbers and MATH -Visuospatial processing (visual representations of images in space) -high functioning parietal lobes perform higher in mental rotation tests

What brain components does amnesia NOT affect?

-intelligence -attention -perception -judgement are all still strongly intact after amnesia occurs

What is the function of the PONS?

-level of arousal (conscious versus asleep) -also relays sensory info to brain and controls some autonomic functions

Describe the early development of Alzheimer's disease.

-memory loss due to neuronal cell death in the HIPPOCAMPUS and basal forebrain (area that produces acetylcholine- the neurotransmitter essential for learning) -results in a quasi- anterograde amnesia (dificult to form new memories)

Describe the mid to late development of Alzheimer's disease.

-plaques and tangles appear in other parts of the brain -other impairments in memory and motor function occur

Describe the characteristics of Alzheimer's Disease.

-plaques and tangles in the brain that build up btw the nerve cells and leave protein deposits called BETA-AMYLOID -these plaques and tangles block communication among nerve cells and disurpt activities that cells need to survive

Describe the characteristics of the OCCIPITAL LOBE of the cerebral cortex.

-primary VISUAL cortex (processes visual signals from your retina) -has connections with motor centers in the brain -certain frequencies of light flashes or images with multiple colors can cause this lobe to trigger body seizures

What are the 3 major classes of amnesia?

1) Anterograde Amnesia (impaired storage of new info) 2) Retrograde Amnesia (loss of old memories) 3) Psychogenic Amnesia (a temporary loss of identity); this class can occur with or without brain injury and involves BOTH short and long term memory loss

What are the 3 different types of glial cells?

1) Astrocytes 2) Microglia 3) Oligodendrocytes

What are the 3 main areas of the brain?

1) Cerebral Cortex 2) Cerebellum 3) Brain Stem

What are the 4 segments of the SPINAL CORD?

1) Cervical 2) Thoracic 3) Lumbar 4) Sacral

What are the functions of an astrocyte (type of glial cell)?

1) Maintain the right chemical environment for neurons. 2) Maintains the Blood Brain Barrier (BBB) that protects neurons from different chemicals

What are the 3 regions of the BRAIN STEM?

1) Midbrain 2) Pons 3) Medulla

What 2 different ways are memories catagorized?

1) Nature (declarative- songs, images, lang, etc.) 2) Time over which it is effective (long and short-term memory)

What are the functions of the ventricles

1) Production of CSF 2) Transmission of CSF

What is the pattern of a typical Action Potential?

1) RMP is "-60mv"; AP is "120 volts" 2) these values are added and RMP shoots up to "+60 mv" 3) RMP returns back to "-60mv" 4) Action Potential releases a inhibitory or excitatory chemical (pos. or neg. neurotransmitter) at the end of the axon

What are the functions of Microglia (type of glial cell)?

1) Remove debris after an immune system response 2) Help with inflammation

What are the 3 types of neurons?

1) Sensory Neurons 2) Interneurons 3) Motor Neurons

What are the 2 divisions of the Peripheral Nervous System (PNS)?

1) Somatic Nervous System 2) Autonomic Nervous System

What are the functions of SENSORY NEURONS?

1) Take external stimuli (taste,touch, smell, etc) 2) Convert this stimuli into electrical & chemical signals OR 3) Respond to internal stimuli (blood pressure, position of joint, or orientation of head)

What are the 3 most vital/ life supporting parts housed in the BRAIN STEM?

1) cardiac center to control heart rate 2) Vasomotor center to control blood pressure 3) Respiratory center in conjunction with the pons

What are the 4 different lobes of the cerebral cortex

1) frontal 2) parietal 3) occipital 4) temporal

What are the functions of Oligodendrocytes (type of glial cell)?

1) lay down myelin which is a lipid structure that surrounds the amxon of a neuron to: a) insulate it b) increase the speed of transmission of the electrical signal

How many neurons are in the human brain? How many connections/ synapses?

100 billion; thousands

What is the weight and consistency of the human brain

3 lbs. Consistency of JELLO

Define "Nuclei" or "Ganglia"

A group of neurons that work together. The body's computer.

Long-Term Potentiation (LTP)

A process which strengthens the connection btw two neurons. The cellular equivalent of a conditioned response.

Define Amnesia

A severe disruption of memory that does not allow the sufferer to remember before,during, or after the trauma.

What effects do chronic drinking have on your memory?

Alcohol damages the frontal lobe (storage of long term memories in the frontal cortex is impaired) via: -shrinking in brain volume -changes in gene expression in brain cells -changes in blood flow in the brain

How does excessive alcohol impair memory?

Alcohol disrupts electrical and chemical activity in the HIPPOCAMPUS and impairs the brain's ability to transfer info from short to long term memory (a form of anterograde amnesia)

Name a common brain disease that causes memory loss?

Alzheimer's disease

Name a brain injury that impairs memory that results from concussions or serious injury.

Amnesia.

How are neurons dramatically reversed?

By changed in the nueronal membrane that allow different ions to move in and out of the cells which causes different voltage lvls at the membrane

What are the functions of MOTOR NEURONS?

Carry INSTRUCTIONS (electrical and/or chemical signals) to EFFECTOR cells (such as skeletal muscles); cause muscles to contract, glands to secrete, etc.

Central Nervous System (CNS)

Central Nervous System (CNS)

What fluid does the brain ride on top of?

Cerebrospinal Fluid (CSF)

Neurotransmitters

Chemcial messages which rely, amplify, and modulate signals between a neuron and another cell

What cells in the brain produce CSF?

Choroid villi

What is the HIPPOCAMPUS responsible for?

Long-term Memory

What is the difference between dendrites and axons?

DENDRITES: "Receivers" that gather signals from other neurons or sensory stimuli; they extend OUT from the neuronal cell body AXON TERMINALS: "Transmit" chemical or electrical signals to other neurons or cells; on the other end of a neuron; LONG extention; allows for SIMULTANEOUS communication between cells

What can injury to the brain stem result in?

Death

What are the two different kinds of extensions called?

Dendrites and axons

What does "ACTION POTENTIAL" measure?

Electrical measurement (in volts)

What are the functions of INTERNEURONS?

Exchange info between neurons to perform thought, complex motor movements and behavior; located in the Central Nervous System (CNS)

What is the name for positive nerotransmitters

Excitatory

What makes neurons unique from other cells?

Extensions are very LONG. Neurons in your brain can send signals all the way down to your legs.

True or False: A stroke is a brain disease.

False.

True or False: Long-Term Potentiation is the cellular equivalent of long-term memory.

False.

True or False: Scientists are sureof the memory loss and reduced brain function in patients with Alzheimer's disease.

False.

True or False: Caffeine can improve motor tasks and recall tasks.

False. Caffeine impairs motor and recall tasks because the levels of acetylcholine are usually low during sleep but are high when paired with caffeine intake. The level of acetylcholine is boosted in your basal forebrain and does not allow for memory consolidation to occur.

True or False: Neurons outnumber glial cells.

False. Glial cells outnumber neurons 10 to 1.

True or False: LTP occurs with all neurons, both activated and inactive.

False. Long-term Potentiation only occurs with activated neurons

True or False: Reflexes are handled by the brain.

False. Reflexes are handled by the spinal cord and do NOT require input from the brain

True or False: The brain is a completely solid structure.

False. The brain is NOT completely solid since it has many interconnection cavities called ventricles

True or False: The right hemisphere of your brain controls the right side of your body.

False. The right hemisphere of your brain controls the left side of your body.

Who can process data from both sides (left & right hemispheres) faster? Males or females?

Females.

What cells are microglia similar to?

Immune cells, because they play a major role in terms of inflammation

What is the name for negative neurotransmitters?

Inhibitory

How do inhibitory (negative neurotransmitters) and excitatory (postive neurotransmitters) affect the ACTION POTENTIAL (AP)?

Inhibitory- Makes it HARDER for AP to occur Excitatory- Makes it EASIER for AP to occur

What are reflexes?

Involuntary responses to stimuli

What is the function of the Central Nervous System?

It integrates the SENSORY info it receives from body RECEPTORS and coordinates MOTOR ACTIVITY through the body; It coordinates, thinks, and play a major role in self-identity

Synapses

Junctions btw axons and dendrites, and where neurons communicate

What is the structure and location of the SPINAL CORD?

Long stretch of azons and neurons that stretch from the brain stem to the lumbar level of the vertebral column (bone that encases & protects the spine)

What causes ISCHEMIC STROKES?

Narrowing of the large arteries in the neck and brain OR blockage of arteries by blood clots or pieces of atherosclerotic plaque (buildup of cell debris on artery walls)

Pre-synaptic neuron

Neuron sending the message before the synapse

Who is at a greater risk for ISCHEMIC STROKES?

People with uncontrolled high blood pressure and diabetes

What is the downside to the Blood Brain Barrier (BBB)?

Physicians have to use powerful drugs that swamp the defense mechanisms of the BBB in order to administer useful drugs to patients with brain diseases.

Which ions are primarily responsible for RMP and AP?

RPM- Potassium ions: Negative voltage; when actional potential reaches a certain value the permeability is altered and potassium ion causes the signal to decrease back to negative (homeostasis conditon) AP- Sodium ions: Positive voltage

What do neurons do?

Receive information, process it, and transmit it to other cells using ELECTRICAL SIGNALS

What do these 4 lobes work together to achieve?

Responses to the environment that are based on intelligence, previous experiences, memory, sensations, and emotion

What is the Cauda Equina and what is its other name?

Roots from the lumbar and sacral segments that thread downward into the base of the vertebral column. Horse's tail.

What is sleep thought to do for your memory?

Sleep is thought to help us learn new info and strengthen our memories by consolidating our memories and therefor strengthening the fewer remaining synapses (fewer synapses during sleep- our brains prioritize and choose to keep the IMPORTANT memories)

What negatively affects WORKING MEMORY?

Stress

What are the complex communication links between neurons called?

Synapses.

Where are spinal taps and epidural injections performed and why?

The Cauda Equina (roots of lumbar and sacral segments) BECAUSE no spinal cord neuronal cell bodies are here ONLY AXONS

What is the connection between the right and left hemispheres called?

The Cerebral Commissure

What other system is the Nervous System most closely linked to?

The ENDOCRINE SYSTEM (the 2nd major coordinating system of the body) that is composed of chemicals that influence cells throughout the body.

What is the simplest/ most common relfex/ neuronal circuit?

The Knee-Jerk Reflex

How is the negativity of the RMP determined?

The concentration of potassium ion inside the cell relative to the outside

In what way doesISCHEMIC STROKES impair memory?

The decrease in oxygen caused a decrease in ATP which lead to neuronal cell death

What is Long-Term Potentiation (LTP)?

The molecular basis of creating long-term identifications (not as complex as memories which can describe not only what something is but how it is done or why) -cellular equivalent of conditioned response 1) signaling between the pre and post-synaptic neurons are patterned (signal repeated) 2) the response of the postsynaptic neuron is stronger than the original signal (response is potentiated) 3) the response lasts for a longer period of time (Long-term identification)

What do the CNS not contain that belongs to the PNS (Peripheral Nervous System)?

The nerves and ganglia outside of the brain or spinal cord

What characteristics do neurons and other cells share?

They have: -Mitchondria that produce ATP -Nuclei that contain DNA -Endoplasmic reticulum (ER) that produce functional proteins

What does injury to the CEREBELLUM result in?

Tremors or shakes of the hands when in motion (not when rested)

Neuron

also called nerve cell; an excitable cell in the nervous system that processes and transmits information by electrochemical signaling.

Frontal Cortex

area of the brain where most types of long-term memory appear to be stored.

What does each spinal nerve enter and thread into before entering the spinal cord?

enters the Dorsal Root Ganglion (DRG) and threads into the dorsal roots

Axon

long projections that send signals from the neurons.

What is another name for the cerbral cortex

the control center of the brain

Memory

the storage, retention, and recall of information including past experiences, knowledge, and thoughts.

What are the interconnection cavities of the brain called?

ventricles