module 1.1-1.4 - biological basis of behavior

genetically predisposed

being naturally more inclined for something because of genes

behavior genetics

the scientific study of how genetic and environmental factors combine to influence differences in behavior and psychological traits

epigenetics

the study of how your behaviors and environment can cause changes that affect how your genes work, without changing your actual DNA sequence

interneurons

neurons within CNS, communication internally and process info between sensory inputs and motor outputs

PNS - Autonomic

involuntary

PNS - Autonomic - Sympathetic

arousing, fight/flight

PNS - Autonomic - Parasympathetic

calms/conserves energy

PNS - Somatic

voluntary actions

glial cells

roles in learning, thinking, and memory

nerve impulse (STEPS)

• neuron receives chemical message

• Electric message builds to trigger THRESHOLD and cause ACTION POTENTIAL

• RESTING POTENTIAL is negative (POLARIZED), neuron becomes DEPOLARIZED to cause positive ACTION POTENTIAL across membranes

• After impulse is transmitted neuron enters a REFRACTORY PERIOD then returns to RESTING POTENTIAL (REPOLARIZATION)

neurotransmitter - acetylcholine

enables muscle action, learning, and memory

with alzheimer’s ACh producing neurons deteriorate

neurotransmitter - dopamine

movement, learning, attention, and emotion

oversupply linked schizophrenia

undersupply linked to tremors/decreased mobility in parkinsons disease

neurotransmitter - sertonin

mood, hunger, sleep, and arousal

undersupply linked to depression

some drugs raise serotonin levels to treat depression

neurotransmitter - norepinephrine

helps control alertness and arousal

undersupply can depress mood

neurotransmitter - GABA

major inhibitory neurotransmitter

undersupply linked to seizures, tremors, and insomnia

neurotransmitter - Glutamate

major excitatory neurotransmitter, involved in memory

oversupply can overstimulate brain, producing migraines or seizures

neurotransmitter - Endorphins

influence perception of pain

neurotransmitter - Substance P

involved in pain perception and immune response

oversupply can lead to chronic pain

substances - psychoactive drugs

chemicals which change moods and perceptions

depressants - alcohol

slows the neural activity in the CNS (brain/spinal cord)

GABA more inhibitory; prevent glutamate reception

slowed processing, memory disruption, reduced self-awareness

depressants - barbiturates

tranquilizers - reduce anxiety without impairing memory or judgement

depressants - opiates

opium and derivatives (morphine, heroin) - depress neural activity, temporary lessening of pain and anxiety

replaces endorphins, increasing likelihood of addiction

stimulants - nicotine

highly addictive psychoactive drug found in tobacco

stimulants - cocaine

produces temporarily increased alertness and euphoria

depletes natural supply of dopamine, serotonin, and norepinephrine

stimulants - AMPHETAMINES

Prescription stimulants used to treat Attention-deficit disorder (ADD)

stimulants - amphetamines - METHAMPHETAMINE

stimulates CNS - accelerated body functions

over time, reduces baseline dopamine levels

stimulants - amphetamines - ECSTASY

synthetic stimulant and mild hallucinogen

produces euphoria and social intimacy

longer-term harm to serotonin-producing neurons and to mood/cognition

triggers dopamine release, but major effect is releasing stored serotonin and blocking reuptake, prolonging serotonin’s feel-good flood

hallucinogens - psychedelic

drugs that distort perceptions and evoke sensory images in the absence of sensory input

hallucinogens - psychedelic - Synthetics

LSD, MDMA, PCP, Ketamine, DXM

hallucinogens - psychedelic - Natural

THC (cannabinoid in marijuana), psilocybins, DMT (ayahuasca), mescaline

hallucinogens - LSD

perceptual distortions and hallucinations have some commonalities

hallucinogens - cannabis

mild hallucinogen - amplifies everything

Franz Gall = Phrenology

an individual's personality, character traits, and mental capacities could be determined by measuring bumps, depressions, and shape of the skull

neuroplasticity

brain’s ability to change by reorganizing after damage or by building new pathways based on experience

neurogenesis

unconfirmed potential for formation of new neurons

tools of discovery - CT scan

structural - uses x-ray to create cross-sectional pictures of the brain

tools of discovery - MRI

structural - use powerful magnets & radio waves to create detailed images of brain structures

tools of discovery - fMRI

functional - uses magnets to measure changes in blood flow in brain while someone does a task

tools of discovery - PET scan

functional - uses a radioactive drug tracer to show activity in brain

tools of discovery - EEG

functional - uses electrodes (small metal disks) attached to the scalp to detect activity

tools of discovery - MEG

functional - spatial distributions of magnetic fields are analyzed

hindbrain

medulla, pons, cerebellum

directs essential survival functions - breathing, sleeping/wakefulness, coordination/balance

midbrain

atop the brainstem

controls some motor movement and transmits auditory and visual information

forebrain

manages complex cognitive activities, sensory and associative functions, and voluntary motor activities

brainstem - medulla

runs involuntary body processes like breathing, heart rate

brainstem - pons

relays signals between the cerebrum, cerebellum, and medulla oblongata

controls vital unconscious processes like sleep and breathing

brainstem - reticular formation

regulates arousal, blocks pain signals traveling through spinal cord

brain stem - thalamus

brain's central relay station, processing and routing almost all sensory and motor signals

cerebellum

sensory processing, coordinating movement & balance, enabling nonverbal learning and memory

limbic system - hypothalamus

keep your body in a stable, balanced state known as homeostasis - connected to pituitary gland

limbic system - hippocampus

explicit memory processing, storage into long-term

frontal lobe

speaking, muscle movements, planning, judgments, personality

parietal lobe

sensory input, body position, pain processing

right hemisphere

making inferences, modulate speech, orchestrate self awareness

pineal gland

secretes melatonin

oxytocin

secreted by bottom of pituitary gland