psych exam 2

dendrite

receives electrochemical signals

soma/cell body

contains nucleus, has dendrites attached to it

nucleus

control center

axon hillock

connects to the axon

myelin sheath

protective, wraps around axons, allows for quicker communication

nodes

gaps in myelin sheath along axon

terminal button

small, at end of axon, release chemical messengers

synapse

site of transmission between two neurons

pre-synaptic

part of synapse that sends chemical signal to another cell

post-synaptic

receiving component of synapse, where neuron detects and responds to chemical signals

neurotransmitters

chemical messenger molecules that neurons use to transmit signals across synaptic cleft to target cells

receptors

specialized protein molecules embedded in the cell membrane that bind to chemical messengers

resting potential

voltage difference when not actively sending signals (-70mV)

concentration of sodium

higher on outside of cell, low in inside of cell

concentration gradient

gradual changes in concentration of substance

electrical gradient

difference in electrical charge or voltage between two regions

threshold of excitation

level of membrane depolarization a nerve cell must reach to trigger action potential (-55mV)

sodium channels

protein that allows sodium ions to pass through cell membrane

sodium pumps

3 sodium ions pumped out, 2 potassium ions pumped in

action potential

rapid temporary change in electrical voltage across a cell membrane that allows neurons to transmit signals

CNS

brain and spinal cord, receives sensory input, processes and integrates data, coordinates all thoughts, movements, and automatic functions

PNS

areas besides brain/spinal cord, communication network

somatic

division of peripheral nervous system that manages conscious sensory perception and voluntary control of skeletal muscle

automatic

component of peripheral nervous system that regulates involuntary processes (heart rate, respiration)

gyrus

rounded ridge or fold on surface of cerebral cortex of the brain

sulcus

shallow crevice, surrounds gyri, increase brain surface area

frontal lobe

intelligence, consciousness, problem solving, rational thinking, last part of brain to develop, prefrontal cortex (executive functions)

parietal lobe

maps world around you, knows where you are, primary motor cortex (motor actions), primary somatosensory cortex (sensory - touch)

temporal lobe

hearing, memory, primary auditory cortex

primary gustatory cortex

sense of perception and taste

primary olfactory cortex

sense of smell

primary motor cortex

planning and executing voluntary functions (posterior frontal lobe)

primary somatosensory cortex

receives and processes tactile and proprioceptive information

homunculi

hands, diners, lips, tongue and face appear large because they require high precision, fine motor skills, or dense sensory receptor

corpus callus

connects two hemisphere, white matter, many axons

thalamus

sends info to part of brain it needs to go, relay station

hypothalamus

basic bodily functions, involved in sleep/wale cycles, tells us when thirsty/hungry, fight/flight

pons

extension of cerebellum, connects cerebellum and spinal cord

medulla

brain stem, keeps you alive, vital functions

cerebellum

hands of back, 50% of neurons, highly involved in movement

spinal cord

axons, many motor neurons, white matter

amygdala

fear, limbic system

hippocampus

declarative memory formation

basal ganglia

movement, remembering how to walk or ride a bike

globus ganglia

core part of basal ganglia, GABA (inhibitors)

caudate

deeps inside brain near thalamus, tail like structure, forms basal ganglia

putamen

outer portion of basal ganglia, motor control

nucleus acummbens

pleasure center, interface between motivation, emotion and motor action