Unit 3 Biological Bases of Behavior

Biological perspective

scientific study of links between biological and physiological processes

Neuron

a nerve cell; basic building block of the nervous system

Soma (cell body)

the part of the neuron that contains the nucleus (cell's life support center)

Dendrite

a neuron's branches/ extensions that receive messages and conduct impulses towards the cell body

Axon

attached to the soma, the neuron extension that passes messages through its branches to other neurons, muscles, or glands

Myelin Sheath

encases axons to enable greater transmission speed/ provides protection and insulation (the jacket for message so they are not leaked)

Multiple sclerosis

loss of muscle movement due to deterioration of the myelin sheath

Terminal branches/ buttons

ends of the axon containing terminal buttons which hold synaptic vesicles that store neurotransmitters

Glial cells

cells that support, nourish, and protect neurons

Action Potential

neural/electrical impulse (aka the message), travels down an axon

Threshold

level of stimulation required to trigger a neural impulse

All or none response

neural firing happens at full response or not at all

Excitatory signal

excitatory neurotransmitters signal trigger actions (gas)

Inhibitory signal

inhibitory neurotransmitter signals depress action (brake)

Resting Potential/ resting state

aka polarized; neuron has a slight negative charge (waiting/ ready for the message)

Selectively permeable

particular about ions entering and ions leaving

Sodium (Na)/ Potassium (K) pump

makes sure the message is sent all the way down the axon

Refractory Period

period of inactivity after a neuron has fired

Polarization

gates are closed, the resting state of the neuron

Depolarization

gates are open, positive ions are rushing in and out

Neurotransmitters

chemical messengers that travel across the synapse and bind to receptor sites on the receiving neuron

Synapse

meeting point between neurons

Synaptic gap/cleft

gap between 2 neurons

Reuptake

sending neuron reabsorbs the excess neurotransmitters

Dopamine

a neurotransmitter that influences movement, learning, attention, and emotion, reward

Acetylcholine

enables muscle action, learning, and memory

Serotonin

good mood; a neurotransmitter that affects mood, hunger, sleep, and arousal

Norepinephrine

helps control alertness and arousal, calms you down; a neurotransmitter that helps control alertness and arousal

Endorphins

neurotransmitter that influences perception of pain or pleasure

GABA

major inhibitory neurotransmitter responsible for sleep

Glutamate

glue for memories; major excitatory neurotransmitter involved in memory

Agonist

exciting neuron firing, increases neurotransmitter action

Antagonist

inhibits neuron firing and blocks/closes the receptor

Nervous system

the body's speedy electrochemical communication network

Nerves

bundled axons of many neurons that rom neural cables connecting CNS with muscles

Sensory (afferent) neurons

carries information from the sense organs to the CNS

Motor (efferent) neurons

carry messages from the CNS to the muscles and glands (ex- moving hand away from candle)

Interneurons

in the spinal cord and receive information from sensory neurons and sends signals back through motor neurons

Central nervous system

comprised of brain and spinal cord; responsible for decision making and coordinating incoming information

Brain

comprised of the cortex and subcortical structures carrying out various functions

Spinal cord

2 way connections between PNS and brain; oversees the sensory and motor pathways

Peripheral nervous system

made up of sensory and motor neurons; connects body to CNS

Somatic

controls the body's skeletal muscles (always voluntary)

Autonomic

controls the glands and the muscle of the internal organs

Sympathetic nervous system

emergency response system, (increase in heart rate when scared, attention focused, muscle tension increase, adrenaline flows, etc.)

Parasympathetic nervous system

default condition of ANS, functions to calm a person (ex- reduce energy expenditure, decrease blood sugar, increase blood flow to digestive organs, etc.)

Hormone

chemical messengers manufactured by the endocrine glands that travel through bloodstream and affect other tissues (influence interests in food, sex, and agression)

Simple Reflex

occurs in spinal cord before information reaches the brain

Endocrine system

the body's "slow" chemical communication system, interconnected with nervous system (endocrine glands secrete hormones, which are chemical messengers)

Adrenal glands

trigger the "flight or fight" response release epinephrine and norepinephrine

Hypothalamus

tells the pituitary gland what to do

Pituitary gland

gland that controls all other glands

Lesion

brain tissue is destroyed and researchers study the impact of functioning

CT/CAT

structure, takes picture slices of brain

MRI

structure, magnetic and radio waves show soft tissue detail

PET scan

function, inject brain to see where it is burning the most

MEG

function, gives detail of blood flow to brain

fMRI

function and structure, combines MRI and PET

EEG

function- detects electrical activity

Medulla

controls heartbeat and breathing

Pons

controls sleep

Reticular formation

controls arousal (alertness) and filters incoming sensory information

Thalamus

relay station for incoming and outgoing sensory information EXCEPT for smell

Cerebellum

processing sensory input, balane, learning, and memory

Limbic system

responsible for emotions and fight or flight

Amygdala

small bean-sized neural cluster in the limbic system; linked to emotion

Hippocampus

processes conscious memories; part of the limbic system

Hypothalamus

directs eating, drinking, and body temperature; governes endocrine system

Cerebral Cortex

information processing and divided into two hemispheres

Frontal Lobe

involved in judgements and decision making

Parietal Lobe

receives sensory input for touch and spatial awareness

Occipital Lobe

included areas that receive information from the visual fields

Temporal Lobe

includes auditory areas and receives information for the ears

Motor cortex

controls voluntary movements

Somatosensory cortex

registers information from skin senses and body movements

Auditory cortex

receives sound information from ears

Visual cortex

receives sight information from eyes

Association areas

involved in learning, things, remembering, and higher level functions

Broca's Area

moves muscles to create speech

Wernicke's Area

process spoken and written language

Plasticity

the brain's ability to change and adapt (especially in childhood)

Neurogenesis

producing new neurons and existing tissue; REBUILDING for plasticity

Corpus Callosum

bundles of axons that connect the brain hemispheres and carry messages between them

Split Brain

severe corpus callosum (isolate hemispheres) to stop seizures and overload of neuron firing

Visual Field

what one eye can see but the other cannot (right retains gather information from left side and vise versa)

Michael Gazzaniga

first psychologist to do split brain research

Left Hemisphere

verbal, speaking, language, logic, math, literal interpretation; controls right side of the body

Right hemisphere

preseptal tasks, making inferences, creativity, visual perception, emotion; controls left side of the body

Dual processing

information is constantly being processed on 2 trials (conscious and unconscious track)

Blindsight

a condition where people who are blind can respond to a visual stimulus w/o consciously experiencing it

Parallel processing

ability to process MANY aspects of a problem at once (unconscious and the information is WELL learned)

Sequential processing

processing one aspect of one problem at one time (conscious and information is new or difficult)

Heredity

genetic transfer of characteristics from parent to offspring

Chromosomes

threadlike structure made up of DNA (46 chromosomes)

DNA

complex molecule containing genetic information; makes up chromosomes

Gene

biochemical units of heredity that make up chromosomes

Monozygotic twins

a single fertilized egg splits into two (SAME gender, genetically identical)

Dizygotic twins

separate fertilized egg (no more alike than siblings SAME or DIFFERENT genders)

Heritability

variation among individuals in a group that we can attribute to genes (varies depending on range of population)

Epigenetics

study of how environment influences your genes