Ch 2

association area- link sensory input with stored memory

Neuron

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

Dendrite

Branchlike parts of a neuron that are specialized to receive information.

Axon

the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands

Neural Impulse

electrical signal traveling down the axon

Myelin Sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

Terminal button

axon terminal containing synaptic vesicles

Afferent neurons

(affect) sensory neurons

Nerve cells that carry impulses towards the central nervous system

Interneurons

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

CNS

Efferent neurons

motor neurons, take to the rest of body

Multiple Sclerosis (MS)

destruction of the myelin sheath on neurons in the CNS and its replacement by plaques of sclerotic (hard) tissue

Guillain-Barre syndrome

autoimmune condition that causes acute inflammation of the peripheral nerves in which myelin sheaths on the axons are destroyed, resulting in decreased nerve impulses, loss of reflex response, and sudden muscle weakness

Action potential

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

excitory and inhibitory

go and stop signals

Depolarization

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

change in membrane potential which allows ions to move between axons

refractory period

a period of inactivity after a neuron has fired

cant have another action potential

Neurotransmitter

chemical messengers that cross the synaptic gaps between neurons

reuptake

process by which neurotransmitters are taken back into the synaptic vesicles

Acetylcholine

A neurotransmitter that enables learning and memory and also triggers muscle contraction

too little: alzheimers

Dopamine

A neurotransmitter associated with movement, attention and learning and the brain's pleasure and reward system.

too much: schizophrenia

too little: tremors and Parkinsons

Serotonin

Affects mood, hunger, sleep, and arousal

too little: depression

Norepinephrine

helps control alertness and arousal; undersupply can depress mood

GABA (gamma-aminobutyric acid)

A major inhibitory neurotransmitter. Undersupply linked to seizures, tremors, and insomnia.

Glutamate

A major excitatory neurotransmitter; involved in memory

too much: migranes

Norapinephrine (Noradrenaline)

hormone form of endorphin

central nervous system

brain and spinal cord, interneurons, body's decision maker

peripheral nervous system

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

somatic/skeletal nervous system

carries sensory input for receptors to CNS + relays commands from CNS to skeletal muscles to control their movements

sympathetic nervous system

arouses heart rate and other processes, slows digestive

parasympathetic nervous system

calms body but speeds digestion

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). Its sympathetic division arouses; its parasympathetic division calms.

afferent neurons (sensory neurons)

take information from the senses to the brain

Interneurons

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

motor neurons (efferent)

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

reflex

A simple, automatic, inborn response to a sensory stimulus, such as the knee-jerk response.

left brain functions

language, logic, writing, math, science, speech

right brain

creative and spatial

corpus callosum

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

split-brain surgery

procedure that involves severing the corpus callosum to reduce the spread of epileptic seizures

Medulla

the base of the brainstem; controls heartbeat and breathing

pons

sleep and arousal

reticular formation

a nerve network that travels through the brainstem into the thalamus and plays an important role in controlling arousal

thalamus

switchboard, relays senses (except smell) to cerebellum

cerebellum

A large structure of the hindbrain that controls fine motor skills, implicit memory

amygdala

fear and aggression

hypothalamus

feeding fighting fleeing fluid fornicate farenheit

hippocampus

long term memories, retrieval

pituitary gland

The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.

adrenal gland

A pair of endocrine glands that sit just above the kidneys and secrete hormones that help arouse the body in times of stress.

frontal lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

parietal lobe

A region of the cerebral cortex whose functions include processing information about touch.

occipital lobe

A region of the cerebral cortex that processes visual information

temporal lobe

A region of the cerebral cortex responsible for hearing and language.

motor cortex

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

sensory cortex

registers and processes body touch and movement sensations

visual cortex

receives written words as visual stimulation

auditory cortex

the area of the temporal lobe responsible for processing sound information

gray matter

processing of sensation, perception, learning

white matter

communications between gray matter and rest of body

phineas gage (accident)

railroad worker who survived a severe brain injury that dramatically changed his personality and behavior; case played a role in the development of the understanding of the localization of brain function

lesion

tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue

aphasia

impairment of language, usually caused by left hemisphere damage either to Broca's area (impairing speaking) or to Wernicke's area (impairing understanding).

Electroncephalogram (EEG)

surface level activity scan, measured by electrodes, sleep studies

computed tomography (CT)

brain-imaging method using computer-controlled X-rays of the brain, static image

pet scan

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

MRI (magnetic resonance imaging)

a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. MRI scans show brain anatomy.

fMRI (functional MRI)

A technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function.

plasticity

the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

neural network

how brain makes conncetions

glial cell

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

broca's area

Controls language expression - an area of the frontal lobe, usually in the left hemisphere, 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 an auditory code, assigns meaning

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