Myers Unit 3

neuron

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

dendrites

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

axon

passes messages away from cell body to other neurons or to muscles or glands.

myelin sheath

a layer of fatty tissue encasing the fibers of many neurons(axon); speeds neural impulses

refractory period

a period of inactivity after a neuron has fired.

threshold

the level of stimulation required to trigger a neural impulse.

all-or-nothing response

a neuron's reaction of either firing or not firing.

synapse; synaptic gap

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. synaptic gap or synaptic clef is the tiny gap between this junction

neurotransmitters

chemical messengers that cross the synaptic gaps between neurons and bind to receptor sites on the receiving neuron,

reuptake

a neurotransmitter's reabsorption

endorphins

opiate-like neurotransmitters linked to pain control and to pleasure.

Agonist

A chemical that mimics and increases the action of a neurotransmitter

Antagonists

Chemical substances that block or reduce a neurotransmitters action

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 (CNS)

the brain and the spinal cord

Peripheral nervous system (PNS)

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

nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs.

sensory (afferent) neurons

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

motor (efferant) neurons

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

interneurons

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

Somatic nervous system

controls the body's skeletal muscles (skeletal nervous system)

Autonomic nervous system

controls the glands and the muscles of the internal organs.

Sympathetic nervous system

arouses the body, expands its energy in stressful situations. (If you get scared)

Parasympathetic nervous system

calms the body, conserving its energy

Reflexes

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

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

Adrenal glands

sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress

Pituitary gland

"THE MASTER GLAND" the endocrine system's most influential gland. under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands

Lesion

tissue destruction.

Electroencephalogram (EEG)

An amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp.

CT (computed tomography) scan

slices brain and examines it by a series of x-ray photographs Aslo called a CAT scan

(PET) Positron emission tomography 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 that distinguish among different types of soft tissues.

fMRI (functional MRI)

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

Brainstem

the oldest part and central core of brain.

Medualla

The base of the brainstem. Controls heartbeat and breathing.

Pons

sleep and arousal

Thalamus

the brains 'sensory switch board' Located at top of brainstem; directs messages to the sensory areas and transmits them to cerebellum and medulla.

Reticular Formation

Plays an important role in controlling arousal.

Cerebellum

"little brain" at the rear of the brainstem; functions including processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory.

Limbic system

A system of neural structures associated with emotions. Includes the Hippocampus, Amygdala and hypothalamus.

Amygdala

2 Lima bean sized neural clusters in the limbic system, linked to emotion. Includes rage and fear.

Hippocampus

processes memories

hypothalamous

it directs several body maintenance activities (eating, drinking, body temperature) helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.

Cerebral hemisphere

two halves of the brain

Glial Cells

Cells in the nervous system that support, nourish, and protect neurons.

cell body

the part of a neuron that contains the nucleus; the cell's life-support center

neural impulse

(action potential) electrical signal traveling down the axon

action potential

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

para thyroids

regulates calcium

Pancreas

regulates sugar level

testis

male sex hormones

ovary

female sex hormones

fight or flight response

surge of energy

cerebral cortex

a thin surface layer of interconnected neural cells

frontal lobes

lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments.

parietal lobe

t the top of the head and toward the rear; receives sensory input for touch and body position

occipital lobes

at the back of the head; includes areas that receive information from the visual fields.

temporal lobes

above the ears; includes the auditory areas

motor cortex

controls voluntary movement

somatosensory cortex

controls body touch and sensations

association areas

involved in higher mental functions such as learning, remembering, thinking, and speaking.

plasticity

brains abillity to change

brocas area

speaking

wernicke areas

understanding

neurogenesis

new neurons being formed

left side controls..right side controls

right side…left side

left hemisphere is more

verbal

right hemisphere is more

visual

corpus callosum

neural fibers connecting the two brain hemispheres and carrying messages between them.

split brain

corpus callosum is cut and the brain hemispheres are isolated

consciousness

awareness

cognitive neuroscience

study of the brain activity linked with cognition

dual processing

information is simultaneously processed on separate conscious and unconscious tracks.

blindsight

a person can respond to a visual stimulus without consciously experiencing it

parallel processing

processing info at the same time (features of a bus)

sequential processing

processing info in steps

behavior genetics

tudy of the relative power and limits of genetic and environmental influences on behavior.

heredity

genetic transfer of characteristics from parents to offspring.

environment

every nongenetic influence

chromosomes

threadlike structures made of DNA molecules that contain the genes.

DNA

a complex molecule containing the genetic information that makes up the chromosomes.

genes

units of heredity that make up the chromosomes

genome

instructions for making an organism

identical (monozygotic) twins

develop from a single fertilized egg that splits in

fraternal (dizygotic) twins

develop from separate fertilized egg that share a prenatal environment

heritability

variation among individuals in a group that we can attribute to genes

molecular genetics

subfield of biology that studies the molecular structure and function of genes.

molecular behavior genetics

study of how the structure and function of genes interact with our environment to influence behavior

epigenetics

the study of environmental influences on gene expression

evolutionary psychology

study of the evolution of behavior usingnatural selection natural selection.

natural selection

inherited traits that better enable an organism to survive and reproduce

mutation

a random error in gene replication that leads to a change

social script

a culturally modeled guide for how to act in various situations.

men think more/less sexually than female

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