Biological Bases of Behavior (Neuroscience)

Unit 2 AP Psychology

Phrenology (Franz Gall)

Thought bumps on the head could reveal our personalities

Biological Psychologist (Neuroscientist)

study the link between biology and behavior

Neuron

a nerve cell, basic building block

Axon

carries messages away to other neurons

Dendtries

receive information

Soma

Cell body -- Keeps cells alive

Myelin sheath

insulates the axon and speeds up impulses (damaged = multiple sclerosis)

Axon terminals (terminal buttons)

make communication with other nerve cells

Glial cells

surround neurons and provide insulation

Sensory neurons (afferent)

carry information from the senses to the brain and spinal cord

Motor neurons (efferent)

carry information from the brain and spinal cord to the muscles and glands

Interneurons

relay information within the brain and spinal cord (have the most of these)

Afferent

Going to

Efferent

Going from

Action potential

brief electrical charge (positive ions coming in)

Refractory period

recharging phase (positive is pumped back out)

Resting potential

neuron is ready to fire when needed (positive outside, negative inside)

Ions

sodium (+) and potassium (-)

Selectively permeable

the axon is selective about what it lets in

All or none response

a neuron either fires or it doesn’t (no in between)

Synapse (synaptic gap)

the space between the axon of one neuron and the dendrite of another

Neurotransmitters

chemical messengers that communicate across the synaptic gap

Acetylcholine

muscle action, learning, memory (not enough = Alzheimer's)

Dopamine

movement, learning, attention (too much = Schizophrenia, not enough = Parkinson’s)

Serotonin and Norepinephrine

mood and arousal (Not enough = depression, too much = mania)

GABA

involved in sleep

Glutamate

involved in memory and learning, comes from food

Endorphins

body’s natural opiates or painkillers (runner’s high)

Agonist

mimics the effects of a neurotransmitter (morphine, heroin)

Antagonist

blocks neurotransmitters (Botox blocks sites for ACh)

Central Nervous System

brain and spinal cord

Peripheral nervous system

connects the CNS to the rest of the body

Somatic nervous system

controls skeletal muscles (voluntary)

Autonomic nervous system

controls automatic (involuntary) functions such as heartbeat and breathing

Sympathetic nervous system

speeds you up, prepares for **fight or flight**

Parasympathetic nervous system

calms the body down and returns to normal

Endocrine system

chemical communication system, a set of glands

Hormones

chemical messengers in the endocrine system

Adrenal glands

above kidneys…arouse body in time of stress (epinephrine and norepinephrine…adrenaline) (cortisol is stress hormone)

Pituitary gland

in brain…controls growth and is the master gland

Pineal gland

back of brain, controls melatonin and sleep rhythms

Thyroid

controls metabolism (thyroxin)

Pancreas

controls blood sugar (insulin)

Ovaries

female reproductive system….release estrogen and progesterone

Testes

release testosterone

Lesion

tissue destruction

EEG (electroencephalogram)

records brain waves

CT scan(computed tomography)

takes x ray photos from different angles

PET scan (positron emission tomography)

injects radioactive form of glucose to highlight areas

MRI (magnetic resonance imaging)

uses magnetic fields for images of soft tissue

fMRI( functional MRI)

shows blood flow and brain function

Brainstem

oldest part, controls automatic survival functions

Medulla

heartbeat and breathing…life support

Pons

right above medulla, coordinates movements

Reticular formation

controls alertness and arousal

Cerebellum

controls balance and coordination

Limbic system

controls emotions and is made up of thalamus, hippocampus, hypothalamus, and amygdala

Hippocampus

controls memories

Amygdala

fear and anger

Hypothalamus

contains pleasure centers…hunger, thirst, sex (Olds and Milner) (maintains homeostasis)

Thalamus

relay station…receives and sends messages to and from the senses (except smell)

Cingulate cortex

emotional processing

Cerebral cortex

outer covering of brain

Frontal lobe

basic knowledge, plans, personality, judgment (Phineas Gage)

Parietal Lobe

Sensory input, touch, feeling

Occipital Lobe

vision

Temporal Lobe

auditory input, hearing

Prefrontal cortex

planning and personality (frontal lobe)

Motor cortex

in frontal lobe, controls movements

Somatosensory Cortex

in parietal lobe, registers touch sensations

Visual Cortex

in occipital lobe

Auditory cortex

in temporal lobe

Association areas

any other part of brain involved in learning, thinking, remembering

Aphasia

language impairment

Broca’s area

controls speech (Paul Broca)

Wernicke’s area

controls understanding of language (Carl Wernicke)

Angular gyrus

controls reading and seeing words

Plasticity

the brain’s ability to reorganize itself

Left brain

controls language, reading, writing, math, speech

Right brain

controls anything creative, music, art, drawing, geometry, spatial skills

Corpus callosum

connects the two hemispheres and allows them to communicate (often cut to prevent epileptic seizures)

Consciousness

awareness of ourselves and the environment

Biological rhythms

varying time periods in our bodies (annual, 24 hours, 90 minutes)

Circadian rhythm

our biological clock; temperature and wakefulness occur on a 24-hour schedule

Beta waves

alert and awake

Alpha waves

slow brain waves in a relaxed state (not asleep)

Theta waves

beginning to fall asleep

Stage 1

hallucination of falling or floating; lasts about 5 minutes

Stage 2

Sleep spindles: bursts of brain activity; Sleep Talking can occur from here on; lasts about 20 minutes

Stage 3

transitional stage; delta waves: begin slow waves in deep sleep

Stage 4

about 30 minutes; hard to awaken; children often wet bed or sleepwalk

REM sleep (stage 5)

Rapid Eye Movement, Vivid dreams occur, heart rate rises, genitals become aroused; also called paradoxical sleep because you are so relaxed

Manifest content

the remembered storyline of a dream (Freud)

Latent content

underlying meaning of a dream, usually sexually related

Activation synthesis theory

Neural activity spreads and dreams are the brain’s attempt to make sense of it

Insomnia

Trouble falling asleep; sleeping pills aggravate the problem; should relax before bedtime, avoid caffeine, drink milk, and don’t nap

Narcolepsy

Uncontrollable sleep attacks…go into REM sleep anywhere; Absence of neurotransmitter hypocretin

Sleep Apnea

Cessations of breathing during sleep; 1 in 20, mostly overweight males; Deprives them of slow wave sleep; Snores all night, tired during day

Night terrors

Being terrified, usually during stage 4 (not 5); Mostly children

Sleepwalking and sleep talking

Runs in families; Younger children because they have longer stage 4 sleep; Decreases over time