Unit 11: Biopsychology

Central nervous system (CNS)

the entire complex of neurons, axons, and supporting tissue that constitute the brain & spinal cord (handles mental activities)

Peripheral nervous system (PNS)

portion of the nervous system that lies outside CNS; afferent fibers of PNS bring messages from sense organs to the CNS; efferent fibers transmit messages from CNS to muscles and glands

Somatic nervous system

sensory & motor neurons that innervate the sense organs & skeletal muscles

Automatic nervous system

involves changes in involuntary bodily functions

Sympathetic nervous system

network of nerves that helps your body activate “fight or flight” mode

Parasympathetic nervous system

network of nerves that relaxes your body after periods of stress/danger; aka “rest and digest”

Neurons

basic cellular unit of nervous system

Dendrites

fine branching extensions that receive incoming nerve signals

Axons

single, long extension that conducts nerve impulses to its branching extensions

Hereditary (nature)

transmission of traits from parents to offspring

Environment (nurture)

the aggregate of external agents/conditions that influence the functions of an organism

Evolutionary perspective

the study of the evolution of behavior and the world, using principles of natural selection

Natural selection

the principle that, among the range of inherited trait variations, those contributing to reproduction and survival will most likely be passed on to succeeding generations

Eugenics

philosophy that seeks to eradicate genetic defects & improve the genetic makeup of populations through selective human breeding —> positive = breeding superior traits, negative = preventing bad breeding

Twin studies

research utilizing twins to assess relative contributions of heredity vs environment

Family studies

research utilizing siblings/parents/kids to assess relative contributions of heredity vs environment

Adoption studies

research utilizing biological parent-child pairs vs adoptive parent-child pairs to assess relative contributions of heredity vs environment

Brain

enlarged, anterior part of the CNS within the skull

Spinal cord

part of the CNS extending from the base of the brain through a canal in the center of the spine

Glial cells

cells in the nervous system that support/nourish/protect neurons

Reflex arc

neural circuit involved in a reflex —> consists of an afferent neuron that sends impulses from receptors to spinal cord

Sensory neurons

a neuron that receives info from environment, via specialized receptor cells, and transmits the info to CNS

Motor neurons

neuron whose axon connects directly to muscle fibers; aka final common path bc it’s final stage of output from nervous system

Interneurons

any neuron neither sensory nor motor but connects other neurons within the CNS

Neurotransmitters

chemicals that can be released by neurons to carry nerve signals between neurons

All-or-nothing principle

a neuron’s reaction of either firing (with a full-strength) reseponse or not firing

Depolarization

reduction in the electric potential across the plasma membrane of a cell, especially a neuron, such that the inner surface of the membrane is less negative than outer surface

Refractory period

a period of inactivity after a neuron has fired

Resting potential

electric potential of a neuron when in nonexcited/resting state

Reuptake

a neurotransmitter’s reabsorption by the sending neuron

Threshold

the level of stimulation required to trigger a neural impulse

Multiple sclerosis

disease of the CNS characterized by inflammation & multifocal scarring —> disrupts neural transmission

Myasthenia gravis

autoimmune disorder in which the body produces antibodies that cause faulty transmission of nerve impulses at neuromuscular junctions

Excitatory neurotransmitters

they excite the neuron and cause it to “fire off” the message —> increases likelihood neuron will fire action potential

Action potential

a neural impulse; a brief electrical charge that travels down an axon

Inhibitory neurotransmitters

blocks/prevents the chemical message from being passed along any farther —> decreases likelihood neuron will fire action potential

Substance p

a peptide involved in pain and neurotransmission

Endorphins

euphoria —> the production of endorphins during intense physical activity is one explanation for a runner’s high or exercise high; increases well being & euphoria, decreases pain

Adrenaline (n)

fight/flight —> produced when stressed —> higher heart rate, high physical boost

Norepinephrine (noradrenaline)

concentration —> affects attention & responding actions in brain —> increased blood flow

Dopamine

pleasure —> also addiction, movement, and motivation; dopamine releases from repeated behaviors

Serotonin

mood —> contributed to well-being & happiness; helps sleep cycle & digestive system

GABA

calming —> calms firing nerves in CNS; high GABA means more focus, low GABA means high anxiety; contributes to motor controls & vision

Acetycholine

learning —> involved in thought, learning, and memory; activates muscle memory in body

Glutamate

memory —> most common neurotransmitter; involved in learning & memory; regulates development & creation of nerve contacts

Hormone

substance secreted into bloodstream by an endocrine gland or other tissue or organ

Adrenaline (h)

secreted in large amounts when an individual is stimulated by stress

Leptin

a protein found in hypothalamus that regulates food intake —> tells you “I’m full”

Ghrelin

a peptide found in hypothalamus that stimulates appetite —> tells you “I’m hungry”

Melatonin

amine hormone found in pineal gland that regulates seasonal changes & influences puberty/sleep-wake cycle

Oxytocin

“the cuddle hormone” —> main function is to facilitate childbirth; promotes positive feelings; aka “love drug/love hormone”

Psychoactive drugs

any drug with significant effects on psychological processes

Agonists

drug that binds to receptor & produces a physiological effect, similar to that of a body’s own neurotransmitter at that receptor

Antagonists

drug that inhibits action of another substance

Reuptake inhibitors

block the reabsorption of neurotransmitters

Stimulants

any of various agents that excite functional activity in an organism

Cocaine

drug that stimulates the CNS with the effect of reducing fatigue & increasing well-being followed by a period of depression

Caffeine

a CNS stimulant in coffee, tea, cola, chocolate, and other over-the-counter meds; an antagonist of the neuromodulator adenosine

Depressants

drugs that, at low doses, depress the inhibitory centers of the brain; at high doses, they depress other neural functions like breathing & heart rate

Alcohol

ethanol —> affects CNS by impairing brain function, leading to impaired brain function

Hallucinogen

substance capable of producing a sensory effect in the absence of an actual stimulus —> produces alterations in perception, cognition, and mood

Marijuana

the principal psychoactive agent in these plants (THC) is concentrated in the resin; when smoked, THC goes to blood —> increases euphoria

Opioids

any group of compounds that include the naturally occurring opiates (ex. morphine) & their semi-synthetic derivatives (ex. heroin); effects = drowsiness, euphoria, mood changes

Heroin

highly addictive opioid; 3x more potent than morphine

Tolerance

condition, resulting from persistent use of a drug, characterized by a markedly diminished effect with regulate use of the same dose of the drug or by a need to increase the dose markedly over time to achieve same effect

Withdrawal symptoms

syndrome that develops after cessation of prolonged, heavy consumption of a substance

Addiction

state of psychological/physical dependence on the use of drugs or substances on activities

Neural firing

the process of a neuron transmitting an electrical impulse (aka action potential) down its axon, away from cell body

Brain

enlarged anterior part of CNS in skull; handles info through parallel processing by distributing tasks across different regions at the same time

Brainstem

connects cerebrum with spinal cord —> includes midbrain, pons, and medulla oblongata —> automatic functions are breathing, heart rate, and digestion

Medulla

bottom part of the brainstem —> carries impulses between spinal cord & higher brain centers; regulates breathing, heartrate, and blood pressure

Cerebellum

“little brain” —> maintains one’s balance, posture, coordination, & fine motor skills; required for some motor conditioning

Cerebrum

largest part of the brain —> makes up most of forebrain; has 2 hemispheres, each hemisphere has 4 main lobes:(frontal, occipital, parietal, temporal

Cerebral cortex

layer of gray matter that covers outside of the cerebral hemispheres in the brain and is associated with higher cognitive functions

Frontal lobe

at front part of brain; largest lobe —> controls voluntary movements, social understanding, thinking, learning, and executive functioning

Occipital lobe

at back of brain; allows people to process & interpret visual stimuli

Parietal lobe

at upper back of brain; receives & interprets signals from other parts of brain so you can understand your environment & state of body

Somatosensory cortex

associated with processing sensory information from the body such as touch, pressure, temperature, and pain

Temporal lobe

at side of head; retrieves memories & understands language and emotion; contains the auditory associated areas & higher order visual processing

Limbic system

loosely defined, widespread group of brain nuclei that innervate each other to form a network involved in autonomic & visceral processes & mechanisms of emotion, memories, and learning

Hippocampus

responsible for your ability to form new memories; required to transfer memories from short to long-term memory

Amygdala

almond-shaped structure in temporal lobe; has viscerosensory & autonomic functions, and has an important role in memory, emotion, perception of threat, & fear learning

Thalamus

processes sensory information (hearing/taste/sight/touch ONLY) and helps w/ memory, planning, & emotions

Hypothalamus

produces hormones, helps you sleep, manages mood/hunger/thirst/sexual arousal/blood pressure/body temp/heart rate

Pituitary gland

“master gland of endocrine system” —> in charge of making several essential hormones; tells other endocrine systems to release hormone

Hemispheres

either of the symmetrical halves of the cerebrum or the cerebellum

Association areas

crucial for integrating & processing sensory information, esp spatial awareness & body image

Linguistic processing

includes prefrontal cortex, motor cortex & Broca’s area

Higher-order thinking

decision-making, problem-solving, & emotional regulationE

Executive functioning

planning, organizing, problem-solving, & self-monitoring behaviors that help us achieve goals & adapt to changing situations

Prefrontal cortex

manages higher-level cognitive functions

Motor cortex

an area at the rear of the frontal lobes that controls voluntary movements