Psychology Ch. 2 – The Brain

Biological Perspective

biology and our behavior and mind – we are biopsychosocial systems! o the body is composed of cells o nerve cells – conduct electricity and send messages to each other o specific brain systems with specific functions o different brain systems send information for sights, sounds, meaning, memories, pain, passion o adaptive brain wired by experience o the body is composed of cells

nerve cells

conduct electricity and send messages to each other

Neurons

nerve cells; basic building blocks of nervous system

dendrite fiber

bushy; receive messages and conduct impulses toward cell body DENDRITES LISTEN

axon fiber

lengthy; sends messages to other neurons, muscles, or glands AXONS SPEAK selectively permeable surface encased in myelin sheath action potential positive outside/negative inside state – resting potential terminal branches

threshold

level of stimulation required for neural impulse stronger stimulus = more neurons firing and more often (ie a SLAP vs a tap) Intensity/speed does not change once fired!!

myelin sheath

insulation of axon that speeds impulses/action potential; fatty tissue that insulates axon; white

action potential

impulse that travels down axon toward axon terminals

resting potential

positive outside/negative inside state

terminal branches

release transmitters to fire or inhibit (threshold) form junctions with other cells

synapse

space between axon tip of sending neuron and dendrite of recieving neuron; neurotransmitters float in this space waiting to bind; or impulse that travels down axon toward axon terminals

neurotransmitters

messengers that cross synaptic gaps, bind to receptor of receiving neuron, and influence whether or not neuron will give impulse; neurotransmitters + receptor = lock and key!

reuptake

neurotransmitters are reabsorbed into sending neurons; applies "brakes" to neurotransmitter

acetylcholine (ACh)

muscle action, learning, and memory; UNDERsupply =Alzheimer’s

dopamine

motor control- movement, learning, attention, emotion; UNDERsupply = tremors and decreased mobility in Parkinson’s disease; OVERsupply = schizophrenia

serotonin

mood, hunger, sleep, arousal; UNDERSUPPLY = depression

norepinephrine

alertness and arousal; undersupply = depressed mood

GABA (gamma aminobutyric acid)

inhibitory neurotransmitter; UNDERSUPPLY = seizures, tremors, and insomnia

glutamate

excitatory neurotransmitter involved with memory;why people avoid MSG in food OVERsupply = seizures and migraines

endorphins

pain control and pleasure; get more naturally by exercising (ie. runner’s high)

The Peripheral Nervous System – PNS

gathers info and transmitts Central Nervous System decisions to other body parts; sensory and motor neurons that connect CNS to rest of body; two components: somatic and autonomic

nerves

electrical cable formed of axon bundles that link CNS with body’s sensory receptors, muscles, and glands

sensory neurons

carry info from sensory receptors to brain and spinal cord

motor neurons

carry info from CNS (brain and spinal cord) to muscles and glands

interneurons

communication in brain between sensory and motor (BILLIONS OF INTERNEURONS)

SOMATIC nervous system (or skeletal nervous system)

voluntary control of our skeletal muscles

AUTONOMIC nervous system (ANS)

self regulated functions; gland and muscles of internal organs; sympathetic division arouses, parasympathetic division calms

sympathetic nervous system

FIGHT OR FLIGHT; arouses and expends energy (ie. accelerates hearbeat, raises blood pressure, perspiration)

parasympathetic nervous system

REST AND DIGEST; calms body; conserves energy (ie. lowers heartbeat, blood pressure, etc)

brainstem

oldest, central core of brain (where spinal cord enters skull at medulla); automatic survival functions

medulla

heart rate and breathing; where cord meets brain

thalamus

top of brainstem; "brain’s sensory switchboard" receiving info from all senses BUT smell; messages directed to cortex and replies to cerebellum and medulla

reticular formation

control of arousal; ie being alert/staying focused

cerebellum

voluntary functions; "little brain" at rear of brainstem; sensory input and movement output

limbic system

system of neural structures; emotion (ie. fear, agression) and drive (ie food, sex); between oldest and newest brain areas; contains hippocampus, amygdala, and hypothalamus

hippocampus

conscious memories

amygdala

emotion and reward centers

hypothalamus

bodily maintenance activities (ie eating, drinking, body temp. endocrine system via purity gland), emotion and reward; below thalamus

cerebral cortex

ultimate control and info-processing center

glial cells

support, nourish, and protect neurons; play role in thinking and learning; "chat" with neurons to transmit info and memory

hemisphere

four lobes, separated by fissures/folds

frontal lobes

behind forehead; voluntary; motor cortex; speaking, muscle movements, plans, judgement

parietal lobes

top of head and rear; sensory cortex – skin and senses

occipital lobes

back of your head; visual cortex

temporal lobes

behind ears; auditory cortex – receives info from opposite ear

motor function

frontal lobe, controls voluntary movement OUTPUT

sensory function

front of parietal lobe, registers touch and movement sensations – INPUT

association areas

uncommited areas; areas not involved in motor or sensory; higher functions – learning, remembering, thinking, speaking

higher functions

learning, remembering, thinking, speaking

brain plasticity

ability to modify itself after damage by reorganizing or building new pathways

neurogenesis

the formation of new neurons

split brain

two hemispheres of brain are isolated by cutting corpus callosum

corpus callosum

fibers connecting two brain hemispheres and relaying info

right hemisphere

o makes inferences o helps makes sentences clear o gives sense of self (ie. can tell we are moving our arm)

Brain Organization and Handedness

• right handedness most common; left more common in males, mathematicians, musicians, artists, reading disabilities, allergies, headaches • right and left mostly process in left hemisphere

A biological psychologist would be most interested in conducting research on the relationship between:
a. neurotransmitters and depression.
b. skull shape and bone density.
c. self-esteem and popularity.
d. genetics and eye color.

a. neurotransmitters and depression.

The function of dendrites is to:
a. receive incoming signals from other neurons.
b. release neurotransmitters into the spatial junctions between neurons.
c. coordinate the activation of the parasympathetic and sympathetic nervous systems.
d. control pain through the release of opiate-like chemical into the brain.

a. receive incoming signals from other neurons.

The minimum level of stimulation required to trigger a neural impulse is called the:
reflex.
threshold.
synapse.
action potential.

threshold

Reuptake refers to:
a. movement of neurotransmitter molecules across a synaptic gap.
b. release of hormones into the bloodstream.
c. inflow of positively charged ions through an axon membrane.
d. reabsorption of excess neurotransmitter molecules by a sending neuron.

d. reabsorption of excess neurotransmitter molecules by a sending neuron.

You come home one night to find a burglar in your house. Your heart starts racing and you begin to perspire. These physical reactions are triggered by the:
a. somatic nervous system.
b. sympathetic nervous system.
c. parasympathetic nervous system.
d. sensory cortex.

b. sympathetic nervous system.

Which brain structure receives information from all the senses except smell?
hippocampus
amygdala
pons
thalamus

thalamus

After Kato’s serious motorcycle accident, doctors detected damage to his cerebellum. Kato is most likely to have difficulty:
a. reading printed words.
b. understanding what others are saying.
c. tasting the flavors of foods.
d. playing his guitar.

d. playing his guitar.

To demonstrate that brain stimulation can make a rat violently aggressive, a neuroscientist should electrically stimulate the rat’s:
a. reticular formation.
b. cerebellum.
c. medulla.
d. amygdala.

d. amygdala.

Auditory stimulation is first processed in the ________ lobes.
a. occipital
b. temporal
c. frontal
d. parietal

b. temporal

The capacity of one brain area to take over the functions of another damaged brain area is known as brain:
a. tomography.
b. phrenology.
c. resonance.
d. plasticity.

d. plasticity

By forming thousands of new neurons each day, monkey brains illustrate:
a. reuptake.
b. hemispherectomy.
c. neurogenesis
d. neural prosthetics.

c. neurogenesis

The corpus callosum is a wide band of axon fibers that:
a. enables the left hemisphere to control the right side of the body.
b. transmits information between the cerebral hemispheres.
c. controls the glands and muscles of the internal organs.
d. directs the muscle movements involved in speech.

b. transmits information between the cerebral hemispheres.

Neurosurgeons have severed the corpus callosum in human patients in order to reduce:
a. Alzheimer’s disease.
b. epileptic seizures.
c. neural plasticity.
d. reward deficiency syndrome.

b. epileptic seizures.

Deaf people who use sign language typically:
a. demonstrate greater mathematical competence than hearing persons.
b. process language in their left cerebral hemisphere.
c. recognize facial expressions of emotion with their left rather than their right cerebral hemisphere.
d. have a smaller corpus callosum than hearing persons.

b. process language in their left cerebral hemisphere.

Left-handedness is ________ common than usual among mathematicians and ________ common than usual among artists.

more; more Left-handedness is more common than usual among mathematicians and more common than usual among artists.

Broca’s area

part of brain used for speaking

Wernicke’s area

part of brain used for understanding language

aphasia

impairment of language

central nervous system (cns)

sensory and motor neurons; brain and spinal cord

agonist

mimics neurotransmitter ie. morphine

antagonist

blocks neurotransmitter ie. blocking ACh would paralyze

true or false: by looking at a piece of a brain, you wouldn’t be able to tell if it was a human’s or a monkey’s.

true! neurons are processed the same by humans and by animals

true or false: stimulating a certain part of a cat’s brain could make it cower at the sight of a small mouse.

true! stimulating the amygdala, responsible for emotion, could produce this effect

true or false: the average person only uses 10% of the brain.

false! all of the brain is related to another part/function; we only KNOW what 10% does, though.

true or false: the brain can generate new brain cells.

true! generating new brain cells is called neurogenesis. the hippocampus is the most likely place for this to occur.

true or false: split brain has many negative effects.

false– split brain has effects, but no ill-effects.

true or false: hearing people process language in the left hemisphere; deaf people process signs in the left hemisphere

true! language is interpreted in the same hemisphere.

In transmitting sensory information to the brain, an electrical signal travels from the ________ of a single neuron.

dendrites to the axon to the cell body
axon to the cell body to the dendrites
dendrites to the cell body to the axon
axon to the dendrites to the cell body

dendrites to the cell body to the axon In transmitting sensory information to the brain, an electrical signal travels from the dendrites to the cell body to the axon of a single neuron.

The speed at which a neural impulse travels is increased when the axon is encased by a(n)

association area.
myelin sheath.
glial cell.
synaptic vesicle.

myelin sheath. The speed at which a neural impulse travels is increased when the axon is encased by a myelin sheath.

An action potential is generated by the movement of

glial cells.
hormones.
vesicles.
ions.

ions. An action potential is generated by the movement of ions.

Schizophrenia is most closely linked with excess receptor activity for the neurotransmitter

dopamine.
epinephrine.
acetylcholine.
serotonin.

dopamine. Schizophrenia is most closely linked with excess receptor activity for the neurotransmitter dopamine.

The body’s natural production of endorphins is likely to be

increased by heroin use and increased by vigorous exercise.
decreased by heroin use and decreased by vigorous exercise.
increased by heroin use and decreased by vigorous exercise.
decreased by heroin use and increased by vigorous exercise.

decreased by heroin use and increased by vigorous exercise. The body’s natural production of endorphins is likely to be decreased by heroin use and increased by vigorous exercise.

Transferring messages from a motor neuron to a leg muscle requires the neurotransmitter known as

dopamine.
epinephrine.
acetylcholine.
insulin.

acetylcholine. Transferring messages from a motor neuron to a leg muscle requires the neurotransmitter known as acetylcholine.

An undersupply of the major inhibitory neurotransmitter known as ________ is linked to seizures.

glutamate
GABA
serotonin
ACh

GABA An undersupply of the major inhibitory neurotransmitter known as GABA is linked to seizures.

Which region of your brainstem plays a role in arousing you to a state of alertness when someone nearby mentions your name?

reticular formation
cerebellum
amygdala
medulla

reticular formation Which region of your brainstem plays a role in arousing you to a state of alertness when someone nearby mentions your name? reticular formation

A brain tumor caused extensive damage to Mr. Thorndike’s hypothalamus. It is most likely that he may suffer a loss of

visual perception.
muscular coordination.
sexual motivation.
language comprehension.

sexual motivation. A brain tumor caused extensive damage to Mr. Thorndike’s hypothalamus. It is most likely that he may suffer a loss of sexual motivation.

The sensory cortex is most critical for our sense of

sight.
hearing.
touch.
smell.

touch. The sensory cortex is most critical for our sense of touch.

Which of the following body parts is associated with the greatest amount of brain tissue in the motor cortex?

arms
face
trunk
knees

face Which of the following body parts is associated with the greatest amount of brain tissue in the motor cortex? face

The auditory hallucinations experienced by people with schizophrenia are most closely linked with the activation of areas in their

motor cortex.
amygdala.
temporal lobes.
hypothalamus.

temporal lobes. The auditory hallucinations experienced by people with schizophrenia are most closely linked with the activation of areas in their temporal lobes.

People’s moral judgments are most likely to seem unrestrained by normal emotions if they have suffered damage to their

cerebellum.
sensory cortex.
corpus callosum.
frontal cortex.

frontal cortex. People’s moral judgments are most likely to seem unrestrained by normal emotions if they have suffered damage to their frontal cortex.

The visual cortex is activated when blind people read Braille. This best illustrates

plasticity.
neural prosthetics.
hemispherectomy.
phrenology.

plasticity. The visual cortex is activated when blind people read Braille. This best illustrates plasticity.