4) Neurobiology and Behaviour Flashcards
What are endorphins used for?
Pain relief
What does damage to the frontal association area lead to?
- Leads to changes in personality
- Responsible for civility (being polite)
What are the functions of myelin sheaths?
- Acts as a catalyst and short circuit
- Insulin and speed of transmission
What is Cuarare? Which neurotransmitter does it affect?
- Acetylcholine - Indigenous drug that is poison; used to kill animals - Produce heart failure
How has the brain evolved to become more intelligent?
It has increased its folds (surface area) through time
How does the top of the brain differentiate from the bottom?
- Top: action
- Bottom: thinking
Which lobe contains the somato-sensory cortex?
Parietal lobes
What are the functions of testosterone?
Sperm count, sexual maturity, and prenatal sexual differentiation
Where is glutamate active in the brain?
In higher brain centers: learning, thought, emotion “hard to sleep”
What does alcohol affect?
Cerebellum
Which neurotransmitter is affected by addiction?
Dopamine
What does the release of GABA promote? Which substances provide GABA release?
- Calming effect - Tranquilizers - Alcohol
What is the function of the Wernicke area?
- Comprehension for spoken and written words
- Unscrambles sounds into recognizable words
What are the 3 primary roles of Acetylcholine?
- Links motor neurons and voluntary muscles (walking, talking) - Important for the Krebs cycle - Involved in memory (old and new)
Which lobes are the eyes connected to?
- Connected to both the right and the left lobe
- Each eye has two visual fields
Which area in the brain expands when you’re blind? Why?
- The somato-sensory cortex
- The cortex adapts to needs: finger touch is bigger (brail)
What are the functions of the limbic system (collectively)?
- Emotion
- Memory (hippocampus)
- Motivation
What are agonists?
- Enhance and improve the action of neurotransmitters - Increases the availability of neurotransmitters by blocking the reuptake
What happens when an impulse reaches the end of an axon?
Tiny sacs are ruptured and neurotransmitters are released
Why does the brain have distinct regions?
Specialized for survival
What happens if the right hemisphere is damaged?
Loses the ability to understand jokes and sarcasm
If an individual has problem with his/her amygdala, what are possible symptoms?
- Problems with facial recognition of emotion
- Trouble recognizing tone of voice
- Docile behaviour
What happens when neurotransmitters are released in the synaptic gap?
- They float in the synaptic gap - Bind to the dendrite of the receiving neuron
What does “all-or-none” mean in terms of neurons?
- Either fires or doesn’t
- Some pulses say fire, some say don’t fire
- The nucleus makes a decision from the summation of the information coming in
What is the central nervous system made up of?
- Brain - Spinal cord
What are the functions of the right hemisphere?
- Non-verbal, puts words in context (Tail and Tale - words that sound the same but have different meanings)
- Facial recognition, art, music, puzzles
What are the functions of the pons?
- Relays messages for movement
- Sleep cycles
- Circadian rhythm (24 hours)
What does the binding of a neurotransmitter cause?
New impulse; may fire or inhibit
What is dopamine responsible for? (2)
- Movement - Emotional arousal
What does PMS affect?
Affects serotonin levels: may lead to anxiety, depression and fluid retention
What does serotonin do in the brain?
- Inhibitory transmitter - Relax, sleep
What are the three types of studies to detect hereditary influences?
- Family Studies
- Twin studies
- Adoption studies
What is an outgoing signal (efferent)?
From our brain to our muscles
Which gland produces growth hormone?
Pituitary gland
What is the resting potential of a neuron at rest?
Slight negative charge
Which neurotransmitter is also a hormone?
Norepinephrine
What are the three basic parts of the neuron?
1) Dendrites
2) Cell body (or soma)
3) Axon
Give examples of antagonists.
Painkillers, anti-psychotic drugs
What happens if the thyroid releases too little thyroxin? What happens if the thyroid releases too much thyroxin?
- Too much thyroxine: hyper, nervous, thin
- Too little thyroxine: sluggish, overweight
Which neurotransmitter plays a role in post-partum depression? How?
- Endorphins - The body adjusts and releases a lot of endorphins - After 48 hours, you have an endorphin withdrawal (depressed)
Which neurotransmitter can cause Alzheimer’s disease?
Deterioration of acetylcholine neurons
Where is the forebrain situated in terms of the cortex?
Sub-Cortical (below cortex)
What are family studies?
- Examines blood-relatives
- Look at who shares genes
- Ex: siblings have a more similar genetic makeup than cousins
What part of the neuron releases neurotransmitters?
Axon terminal
What is the function of the somatic nervous system?
- Control of our VOLUNTARY movements
- Eyes, hands, muscle contraction
What hormones do the ovaries produce?
Estrogen and progesterone
Is caffeine an agonist or antagonist? How?
- Agonist - It increases the availability of glutamate, which makes you active and awake - It mimics the action of the drug artificially - It isn’t the caffeine that makes you awake, it’s what the caffeine does to your brain chemistry
Which neurotransmitter does LSD affect?
- Decreasees action of serotonin - Inhibits the inhibitor - Hallucinations
What is the absolute refractory period? How long does it last?
- 1-2 miliseconds
- No firing
What % of neurons release glutamate?
40%
If ________ is affected, we might not be able to move properly.
Acetylcholine
What is the peripheral nervous system made up of?
All parts of our nervous system except for the brain and spinal cord
What is psychosis?
A lack of reality
What are some advantages of being left-handed?
- Tend to do better at mathematics
- Post-stroke language recovery
What are twin studies? What results show heredity?
- Compare identical twins (M2) and fraternal twins (D2), which controls for environment
- If M2 shows greater similarity on a trait than D2: heredity
What is the structure of the thalamus? What are its functions?
- Two egg-shaped structures above the brainstem
- Relay center for messages on the way to the cerebral cortex
What are the functions of glial cells?
Support services, nutrition, removes waste, helps the production of myelin sheath
What is the endocrine system?
- Series of glands that manufactures and releases hormones
- Released in one part of the body, and affects something else
- Carried by the bloodstream to reach the target
What are endorphins triggered by?
Drugs like opium, heroin, and morphine
Which neurotransmitter does an orgasm affect?
An orgasm is a dopamine rush
Where are the adrenal glands located?
Just above the kidneys
Females have thicker ________________
corpus callosums
What is the function of the parasympathetic nervous system?
- Almost the exact opposite effect of the SNS
- Relaxes the body and inhibits or slows many high energy functions
- Resting Heart Rate is returned to homeostasis: 60bpm
Differentiate sensory and motor neurons.
- Sensory neurons: incoming messages by our body receptors
- Motor neurons: outgoing from the brain
Where is the occipital lobe located?
In the back of the brain
What happens if you damage the hippocampus?
You can’t form new memories
What is a CT scan? What is its function?
- Rotating X-Ray
- Cross-sectional view of the brain
- Common in concussions, and head injuries
What can “highjack” the frontal cortex?
The amygdala
Deficient levels of which neurotransmitter are linked to mood disorders?
Serotonin
How do neurons communicate?
1) Incoming signal changes the ions balance
* Positive ions rush in (K+ and Na+)
2) Causes depolarization (inside is less negative than outside)
* Negative ions (Cl-) are forced out
3) Ionic change leads to an impulse
* This is called the action potential: “The spark”
4) Once passed, the original balanced is restored; ready for the next impusle
* Repolarization
What is the function of the sympathetic nervous system?
- Prepares the body for intense physical activity
- Raises heart rate: fight or flight syndrome
Which test can be used to see the brain in action?
Functional MRI (f/MRI)
How does each side of the brain see this?
D
D
D
D
D
D
D
D D D D D D D
- Left-side: a bunch of D”s
- Right-side: the letter L
- Both work together
What does too much dopamine cause?
- Schizophrenic behavior - Psychosis
What is the major function of the pituitary gland?
- “Master gland” since it bosses around
- Releases hormones that activates other glands
What is “split brain”?
- When the corpus callosum connecting the two hemispheres is damaged to some extent
- You functionally have “two” brains: right side and left side are NOT integrated anymore
What is the function of the dendrite?
Receives signals from other neurons
Where is the pituitary gland located?
At the base of the brain
How would the SNS and PNS react to a stressor?
- Stressor raises the heart rate through SNS
- PNS returns it to normal afterwards
All senses pass through the _____________ except ________. Why?
- thalamus, smell
- Survival mechanism: smell first before eating (oldest sense)
What hormone does the pancreas secrete? What happens when there are low levels?
- Hormone: insulin; needed to extract glucose from the blood
- Low insulin: diabetes, cannot breakdown blood sugar
A group of boys and a group of girls are asked to think of something sad. Who generates a greater response? Where?
- Girls generate a greater response
- Greater activity in the limbic system
Which structure of the brain separates us from other animals?
The cerebrum
Which hormone is associated with “fight or flight” syndrome?
Norepinephrine
What are the functions of the amygdala?
- The brain’s alarm system
- The key to emotions; especially fear
- Emotional reactions are faster than conscious ones
- Fast, BUT sloppy
What does Prozac target?
- Targets serotonin neurons - Calms the indvidual
What are the functions of the medulla?
- Basic survival functions:
- Heart-rate
- Breathing
- Swallowing
- Orgasm
What composes 50% of the brain?
Glial cells
Which section of the brain explains why children have lower attention spans than adults?
- The Reticular Activating System
- Filters out low level messages to avoid overload
- Not matured until adolescence
Differentiate dominant and mixed laterality.
- Dominant: individual uses right-side for everything
- Mixed: individual uses right-hand but left-foot
What does norepinephrine cause in terms of mood?
Excitatory, arousal and mood
Which neurotransmitter does ecstacy affect?
- Increases serotonin - Danger
How much does our brain weigh?
1.5 kg
Where is the pineal gland located?
In the brain
What is the major function of the pineal gland? What does it secrete?
- Regulates sleep rhythm
- Hormone secreted is melatonin
What is an unconditioned reflex?
- Comes with the territory - Survival value
How many lobes does the brain have?
8 lobes
What are anabolic steroids?
- Artificial testosterone
- Advantage for athletes
- Cause bigger problems (even death)
Which section of the brain is the trigger for “fight-or-flight”? After how much time? What happens if it takes longer than that?
- The amygdala
- 1/4 seconds
- After, the information reaches the frontal cortex, which would “damp things down”
What is the key structure in the brain that determines whether short-term memories get translated into long-term memory?
Hippocampus (part of the limbic system)
What are evolutionary forces that account for gender differences in the brain?
- Man the hunter: aggressive
- Woman the caregiver: emotional
What is brain plasticity? Who does it favor?
- The brain’s ability to “re-wire” itself after an injury
- Plasticity decreases with age; kids are more plastic
- Women tend to be more plastic
Which lobe is the largest?
The frontal lobe
Why are people with autisim “slower”?
Because of a lack of myelin sheath
What are the three parts of the synapse?
- Axon terminal - Gap - Dendrite
What are the four components of the hindbrain?
- Medulla
- Pons
- Cerebellum
- The Reticular Activating System
What does damage to the hippocampus lead to?
Leads to NO new memories
What three areas are laterality associated with?
- Hands
- Eyes
- Feet
When is handedness established? Which gene is it likely to be established by?
- Before birth
- Single gene in female “X” chromosome
What separates the two hemispheres of the cerebrum?
The corpus callosum
What are the adrenal glands turned on by?
Turned on by ACTH: message from the pituitary
What are the functions of the Frontal Association Area? Where is it located?
- Frontal Lobe (beneath speech)
- Thinking
- Impulse control
- Planning for the future
- Emotions (generated and controlled)
What does too little dopamine cause?
Parkinson’s disease
What are the structures of the limbic system?
- Amygdala
- Hippocampus
Females have thicker corpus callosums. What is the consequence?
- Greater emotional awareness
- More aware of their world than boys
What does a lack of GABA cause?
Epilepsy and seizures
What does EEG stand for? What is its function?
- Electroencephalogram
- Measures 4 types of brain waves
- Used for sleep studies
How long is short-term memory?
30 seconds
What happens if you damage the Broca’s area?
- Broca’s aphasia
- Understand things but cannot speak
What is the primary function of the occipital lobe?
Vision
What is polygenetic inheritance?
Trait is determined by more than one pair of chromosomes
What damage is behind not being able to differentiate the feel between sandpaper and silk?
The somato-sensory cortex
Where is the thyroid located?
In the throat
Which neurotransmitter do anti-psychotic drugs target?
Block dopamine sites
What is the issue of forced change? What can it cause?
- Trying to force a left-handed person to a right-handed person (ex: in Italy - Christianity)
- You can end up with a speech impediment since the areas of the brain are in close association
What are neurotransmitters?
Endogenous drugs produced by neurons
What are the two major functions of the hippocampus?
1) Essential for new memories
2) Plays a role in neural maps
What does cocaine do?
Blocks the reuptake of dopamine
What are adoption studies? What does it show?
- Biological (genetic) vs. Adoptive (environmental) parents
- Shows whether the individual’s behavior had any genetic implications
What is the basic split of the brain?
A) Cerebral cortex
- Higher brain function
- Action
B) Associated Areas
- Thought (thinking, perceiving, understanding), but no action
- Below the cortex
Do males and females use the same pathways for the same task?
No, they use different pathways (shown through f/MRI studies)
Which section of the hindbrain is sensitive to drugs and alcohol?
Cerebellum
Where is norepinephrine produced?
- Locus coeruleus (brain stem)
What is the function of the association areas of the occipital lobe?
Hold memories of past visual experiences
Where is the Wernicke area located?
In the left temporal lobe
The _________ is composed of 2 hemispheres.
cerebrum
Is glutamate excitatory or inhibitory?
Primary excitatory
What are the two components of the forebrain?
- Thalamus
- Hypothalamus (below the thalamus)
The right and left hemispheres have some specialized functions, which is called ______________
lateralization
Which neurotransmitter provides the runner’s high?
Endorphins
What is the function of the somato-sensory cortex?
- Reception and processing of:
- Touch, pressure, temperature, pain
If the _____ is damaged, it can lead to a coma.
pons
What is the Babinski reflex?
When you touch a baby’s foot and the toes flex
What are the 2 roles of endorphins?
- Involved in breathing and respiration - Involved in hunger regulation
How do “outside” drugs act?
- They block or release endogenous drugs - They affect things indirectly
What is the function of the automatic nervous system?
- Control of internal bodily functions
- Heart, digestion, breathing, etc.
- Does these functions AUTOMATICALLY
Where is the cerebral cortex related? What is it?
Thin layer on top of the cerebrum covering about 1/4 inch thick for higher order thinking
What is the cross-over effect?
Right-side of the brain controls the left-side of the body, and vice-versa (chiasmic effect)
What are the three types of neurons?
- Afferent neurons
- Efferent neurons
- Interneurons (most neurons, in between)
Give an example of an agonist.
Cocaine
What are glutamate and GABA chemically?
Both are amino acids
What neurotransmitter affects Parkinson’s?
Acetylcholine (too much)and dopamine (too little)
What is transduction?
- Converting one form of energy to another
- The only language the brain reads is electricity
What do endorphins provide? Why?
- Floating calm - Because it is an inhibitory neurotransmitter
What are the functions of the left hemisphere?
- Verbal, listening, talking, analysis
- Step-by-step procedures
What are the three tasks of a neuron?
1) Receive incoming messages - Transduction
2) Integrate (takes information and makes it apart of a system)
3) Transmit
What is the function of the cell body of the neuron? What is it also called?
- Soma
- Contains the nucleus
- Carries out metabolic functions (fire or don’t fire)
Which brain center controls hunger?
Hypothalamus
Which lobe is the Broca area located in?
The left frontal lobe
Is GABA excitatory or inhibitory?
Main inhibitory, controls anxiety
Where is the pancreas located?
Between the stomach and intestines
What does the primary motor cortex separate?
The frontal lobe and the parietal lobe
What happens to unused neurotransmitters?
- “Sucked back” (re-uptake) to the axon terminal - The key can’t find anything to do so it comes back to be used again
What is the function of the Broca’s area?
Speech; it is a MOTOR action
What does MRI stand for? What can it illustrate?
- Magnetic Resonance Imagery
- Reveals brain structure
What are the functions of the cerebellum?
- Coordination, movement, posture, balance
- Learning motor skills
- Orchestrates everyday movement
- Role in habit formation
What are the four causes of gender differences in the brain?
1) Evolutionary forces
2) Structural differences
3) Pathways of the brain
4) Limbic response
How many neurotransmitters have been identified?
More than 50
What is the function of the temporal lobes? Where are they located?
- Located at the temples (above the ear)
- Hearing: receives sounds from both ears
- Allows you to know the direction of sound
What is the major function of the thyroid gland? What does it release? What does it control?
- Controls how the body burns energy (metabolism)
- Releases thyroxin, which controls metabolism
Which area is the motor cortex close to (and best friends with)? Why?
- Somatosensory area
- We sense something; then we have to move
Where are the parietal lobes located?
Located on top, behind the frontal lobes
What hormones do the adrenal glands produce? What is their function?
- Produces epinephrine and norpinephrine
- Activate the sympathetic nervous system (SNS)
What is an incoming signal (afferent)?
From our environment to our CNS
What is the function of the motor cortex? Where is it located?
- A strip of tissue at the back of the frontal area
- Controls voluntary movement
Which neurotransmitter does speed affect?
Norepinephrien
Describe the hierarchy of the nervous system.
Central Nervous System (CNS)
- Brain
- Spinal Cord
Peripheral Nervous System (PNS)
- Somatic
- Automatic (Sympathetic & Parasympathetic)
What does PET mean? What is the function of a PET scan?
- Positive Emission Tomography
- Reveals brain activity
- Injects radioactive glucose, or inhale oxygen with low-radioactivity
- Looking at how the brain consumes glucose/oxygen
What are the functions of the reticular activating system?
- Attention and arousal
- Turns brain on; indicates messages coming in
- Activates higher areas of the brain
Which neurotransmitter does cocaine influence?
Promotes release of dopamine and blocks reuptake
Are there more left-handed males or females?
Males
What are the functions of the hypothalamus?
- Body’s thermostat: regulates basic drives
- Hunger
- Sex (sexual urges), refractory period (men)
- Thirst
- Temperature
- Emotional control
- Nervous sweat (linked to temperature and emotional control)
Which neurotransmitter causes depression or bipolar disorder at low levels?
Norepinephrine
Severe epilepsy causes a surgeon to cut the corpus callosum of an individual. What would they respond when asked questions about AIR·PORT
1) What did you see?
2) Point with your LEFT hand to what you saw.
1) Reads PORT since the verbal (language) is on the left side
2) Points to AIR
How do neurotransmitters bind to the dendrite of the receiving neuron?
- Lock and key process - Each neurotransmitter has a specific shape (key) and fits into a receptor (lock)
What are antagonists?
Drugs, chemicals that block the action of a neurotransmitter by occupying the receptor site