AP Psych Brain Unit

nervous system

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

central nervous system

brain and spinal cord

peripheral nervous system

the sensory and motor neurons that connect the central nervous system to the rest of the body

somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles

autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart).

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, expending its energy in stressful situations

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy

brain

The mass of nerve tissue that is the main control center of the nervous system. It enables thinking feeling, and acting.

spinal cord

connects the peripheral nervous system to the brain

Reflexes

automatic responses to sensory stimuli, such as the knee-jerk response

Interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

Hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

biological psychologists

the scientific study of the links between biological and psychological processes

neuron

a nerve cell; the basic building block of the nervous system

dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

axon

A threadlike extension of a neuron that carries nerve impulses away from the cell body.

myelin sheath

covers the axon of some neurons and helps speed neural impulses

cell body

the cell's life support center

neural impulse

electrical signal traveling down the axon

action potential

a neural impulse; a brief electrical charge that travels down an axon

resting potential

The difference in electric charge between the inside and outside of a neuron's cell membrane. (interior negative and outside positive)

Depolarization

The process during the action potential when positive ions are rushing into the cell causing the interior to become more positive.

refractory period

a period of inactivity after a neuron has fired

excitatory

accelerates neuron's firing speed

inhibitory

inhibit the next cell from firing

threshold

the level of stimulation required to trigger a neural impulse

all-or-none response

a neuron's reaction of either firing or not firing

sensory neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

motor neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

Synapse

the meeting point between neurons

synaptic cleft

gap between adjacent neurons

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

Reuptake

a neurotransmitter's reabsorption by the sending neuron

Hypothalamus

brain region controlling the pituitary gland

pituitary gland

The endocrine system's most influential gland. It releases hormones that influence growth and controls other endocrine glands.

adrenal gland

Release epinephrine and norepinephrine. It arouses the body when stressed.

Thyroid

regulates metabolism

parathyroid

regulates the levels of calcium in the blood

pancreas

Regulates the level of sugar in the blood

testis/ovaries

secretes male/female sex hormones

EEG

An amplified recording of the waves of electrical activity that sweep across the brain's surface.

CT

examines the brain by taking x-ray photographs that can reveal brain damage

PET

a display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

MRI

uses magnetic fields and radio waves to produce images of the brain's soft tissue

fMRI

A technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. (where it's active, blood flows)

brainstem

the oldest structure of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions

thalamus

the brain's sensory switchboard, located on top of the brainstem; It directs information from the senses to the higher brain areas.

reticular formation

a nerve network in the brainstem that plays an important role in controlling arousal

cerebellum

the "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating voluntary movement and balance

limbic system

neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives.

Amygdala

two lima bean-sized neural clusters in the limbic system; linked to emotion (aggression and fear).

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward (pleasure).

cerebral cortex

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center.

Cerebrum

Largest part of the brain; responsible for our conscious actions

glial cells

cells in the nervous system that support, nourish, and protect neurons

frontal lobes (prefrontal cortex)

the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments

parietal lobes

portion of the cerebral cortex lying at the top rear part of the head; receives sensory input for touch and body position

occipital lobes

portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields

temporal lobes

portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear

motor cortex

an area at the rear of the frontal lobes that controls voluntary movements

sensory cortex

area at the front of the parietal lobes that registers and processes body touch and movement sensations

Visual cortex

The visual processing areas of cortex in the occipital lobes.

auditory cortex

the area of the temporal lobe responsible for processing sound information

association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

Phineas Gage

railroad worker who survived a severe brain injury that dramatically changed his personality and behavior after massive frontal lobe damage

underside of right temporal lobe

enables us to recognize faces

Broca's area

Controls language expression - an area of the left frontal lobe that directs the muscle movements involved in speech.

Wernicke's area

controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe

angular gyrus

transforms visual representations into auditory code (reading aloud)

Plasticity

the brain's ability to modify itself after damage by reorganizing neural tissue. Other parts of the brain may compensate if an area is damaged.

neurogenesis

the formation of new neurons

lateralization

hemispheric specialization

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

split brain

a condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them

consciousness

our awareness of ourselves and our environment

cognitive neuroscience

the interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language)

dual processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks

circadian rhythm

the biological clock; regular bodily rhythms that occur on a 24-hour cycle

what can affect circadian rhythm

1. light

2. temperature

suprachiasmatic nucleus (SCN)

In response to light, it causes the pineal gland to adjust melatonin production, thus modifying our feelings of sleepiness

REM sleep

Rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active.

alpha waves

the relatively slow brain waves of a relaxed, awake state

sleep

natural loss of consciousness

stage 1 sleep

Slowed breathing and irregular brain waves.

Hallucinations

false sensory experiences

stage 2 sleep

Now more relaxed and clearly asleep.

sleep spindles

bursts of rapid, rhythmic brain-wave activity

stage 3 and 4 sleep

deep sleep

delta waves

the large, slow brain waves associated with deep sleep

REM sleep characteristics

rapid brain waves, heart rate and breathing increase, aroused genitals, relaxed muscles, storylike dreams

Effects of sleep loss

vulnerable to obseity, stress, fatigue, impaired concentration, depressed immune system, greater vulnerability to accidents, slowed performance

insomnia

recurring problems in falling or staying asleep

Narcolepsy

characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep, often at inopportune times.

cause of narcolepsy

lack of hypothalamic cells that produce and release orexin

sleep apnea

characterized by temporary stop of breathing during sleep and repeated momentary awakenings (associated with obesity)

night terrors

characterized by high arousal and an appearance of being terrified; unlike nightmares, they occur during Stage 4 sleep, and are seldom remembered

dreams

a sequence of images, emotions, and thoughts passing through a sleeping person's mind

REM dreams

vivid, emotional, bizarre