Unit 2: The Brain (AP Psychology)

does not include parts of the brain

Dopamine

• neurotransmitter that influences movement, learning, attention, and emotion (involved in risk and reward)

• (DO)pe-a-mine — keeps us motivated

Acetylcholine

• enables muscle, learning, and memory

• A LAM (Learning, Action, Memory)

Seratonin

• affects mood, hunger, sleep, and arousal

• “When you feel happy the serotonin is workin”

Norepinephrine

• controls alertness and arousal

• NOREpinephrine = NO REST

GABA

• major inhibitory

• B stands for BREAK

Glutamate

• major excitory

• Glutamate just can't wait

Endorphins

• influence perception of pain/pleasure (natural opiod)

• Dolphins sound like endorphins → dolphins can be very happy

Substance P

• involved in pain perception and immune response

• P = Pain Perception

Neuron

• make up the nervous system

• nerve cell

Dendrites

• receive signals

• bushy, branching extension

axon

• send signals

• a long, thin fiber extending from a nerve cell

myelin sheth

layer of fatty tissue around the axon to enable greater transmission speed

glial cells

• “glue cells”

• support, nourish, and protect neurons

action potential

• neural impulse

• brief shift in a neuron’s electrical charge that travels down an axon

• ***when the excitatory impulses are greater than the inhibitory impulses***

refractory period

• “down time”

• period of rest time after a neuron fires

• AKA absolute refractory period

firing threshold

the minimum level of stimulation required to trigger an impulse (action potential)

all-or-none response

neural impulse either fires or doesn’t fire

synaspse / synaptic gap

• gap between 2 neurons

• crossed by neurotransmitters

neurotransmitters

chemical messengers that travel across the synapse

reuptake

the reabsorbing of excess neurotransmitters by the sending neuron

agonist

increase neurotransmitter action

antagonist

decrease neurotransmitter action

depolarization

when positively charged ions rush into the axon

Multiple Sclerosis

degeneration of the myelin sheath can lead to this

Myasthenia Gravis

• disease resulting from the blockation of Acetylcholine (ACh) — disrupts communication between nerve and muscle cells

• results in muscle weakness

central nervous system

brain and spinal chord (decision maker)

peripheral nervous system

gathers information and send central nervous system decisions to body parts

nerves

• cluster of axons

• DIFFERENT FROM A NERVE CELL/ NEURON

sensory neurons vs. motor neurons

• Sensory — carries messages to the brain

• Afferent

• Motor— carries messages from the brain

• Efferent

interneurons

process information between 2 neurons

somatic nervous system

• voluntary muscle control

• part of the peripheral nervous system

autonomic nervous system

• gland and internal organ control

• part of the peripheral nervous system

sympathetic nervous system

• arouses and expends energy (fight or flight)

• increased heart rate, increased blood pressure, decreased digestion

• part of the automatic nervous system, which is part of the peripheral nervous system

parasympathetic nervous system

• conserves energy (rest and digest)

• lowers heart rate, lowers blood pressure, increases digestion

• part of the automatic nervous system, which is part of the peripheral nervous system

reflex arc

a fast, automatic nerve pathway that controls an involuntary response to something

endocrine system

secretes hormones into the blood, which travel and affects the brain

hormones

• chemical messengers produced by the endocrine system's glands

• last longer than neurotransmitters

• influence lots of things like aggression, hunger, and interest in s*x

Oxytocin

hormone that facilitates reproduction and social support

Adrenaline

• secreted by adrenal glands

• hormone that increases heart rate, blood pressure and sugar

adrenal glands

• controlled by sympathetic nervous system

• secretes adrenaline

pituitary gland

• tells other glands to release hormones (MOST INFLUENTIAL GLAND)

• controlled by the hypothalamus

MRI

• one of the most detailed brain exams

• shows soft tissue through magnetic fields

CT scan

• x-ray of the brain

PET scan

• shows brain activity through consumption of fuel

• glucose “lights up”

EEG (electroencephalogram)

• shows electrical activity in brain

• amplified tracing of brain waves

MEG (magneroencephalography)

• measures tiny magnetic fields

fMRI

• shows brain’s functioning

• blood flow

Substance Use Disorder

continued substance use that disrupts life

Psychoactive drugs

chemicals that alter the brain

Stimulants

• excite neural activity and increase body functions

• Examples include caffeine, cocaine, and metaphetamine

Depressants

• calm neural activity and slow body functions

• Examples include barbiturates, opiods (heroin), and alcohol (a depressant in ALL amounts)

Hallucinogens

• distort perceptions and evoke sensory images

• Examples include LSD, marijuana, estacy