Unit 1: Biological Bases of Behavior

biological psychology

A branch of psychology concerned with the links between biology and behavior

neuron

A nerve cell; the basic building block of the nervous system

sensory neurons

Neurons that carry incoming information FROM the sensory receptors TO the brain and spinal cord

motor neurons

Neurons that carry outgoing information FROM the brain and spinal cord TO the muscles and glands

interneurons

Neurons within the brain and spinal cord that translate sensory neuro info for the motor neurons

myelin sheath

A protective layer of fatty tissue that surrounds axons, facilitating faster transmission of electrical signals between neurons.

action potential

A brief electrical charge that travels down the axon of a neuron, initiating neurotransmitter release and signaling between neurons.

neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons that transmit signals from one neuron to another, facilitating communication within the nervous system

reuptake

A neurotransmitter's reabsorption of excess chemical message by the sending neuron when the receiving neuron has accepted all of the message it can at that time.

endorphins

Neurotransmitters linked to pain control and to pleasure

nervous system

The body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

central nervous system

The brain and spinal cord that coordinate the activities of the body and process information.

peripheral nervous system

The sensory and motor neurons that connect the central nervous system to the rest of the body, including all muscles and organs.

somatic nervous system

The division of the peripheral nervous system that controls voluntary muscle movement.

autonomic nervous system

The division of the peripheral nervous system that controls the automatic functions/glands (such as the heart and lungs).

sympathetic nervous system

The division of the autonomic nervous system that arouses/excites the body, mobilizing its energy in stressful situations (triggers during fight or flight).

parasympathetic nervous system

The division of the autonomic nervous system that CALMS the body, usually after stress/threat has passed.

reflex

A simple, automatic response to a sensory stimulus, such as the knee-jerk response

hormones

Chemical messengers that are made by the endocrine glands, travel through the bloodstream, and affect other tissues

pituitary gland

The endocrine system's most influential gland. Regulates growth and controls other endocrine glands

lesion

Tissue destruction; a brain lesion is a naturally or experimentally caused destruction of brain tissue

electroencephalogram (eeg)

An recording brain waves (electrical activity) - These waves are measured by electrodes placed on the scalp

fMRI (functional MRI)

A brain-imaging technique that shows bloodflow to active areas of the brain to show function.

brainstem

part of the brain that connects the brain to the spinal cord and is responsible for regulating automatic survival functions such as heart rate and breathing.

medulla

lowest part of the brainstem, located just above the spinal cord, and is essential for regulating vital autonomic functions such as heart rate, blood pressure, and respiration.

reticular activating system

A nerve network in the brainstem that plays an important role in controlling arousal/alertness

thalamus

"The brain's sensory switchboard" responsible for processing and relaying sensory information, playing a crucial role in regulating consciousness and alertness.

cerebellum

Located at the rear of the brainstem, responsible for regulating motor control, balance, coordination, and certain cognitive functions such as attention and language.

limbic system

System (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; plays a key role in the processing of emotions such as fear, pleasure, and aggression, as well as influencing behaviors related to survival and reproduction

amygdala

Two lima bean-sized neural clusters in the limbic system that play a key role in processing emotions, particularly fear and pleasure.

hypothalamus

A neural structure lying below the thalamus that plays a critical role in homeostasis by regulating various autonomic functions such as temperature

cerebral cortex

A layer of neurons over both hemispheres of the brain, involved in various higher brain functions including cognition, perception, and voluntary motor actions.

glial cells

Cells in the nervous system that support, nourish, and protect neurons

frontal lobes

Portion of the cerebral cortex lying just behind the forehead. Involved in various higher cognitive functions, including reasoning, planning, problem-solving, and emotional regulation

parietal lobes

Portion of the cerebral cortex lying at the top of the head and toward the rear, involved in processing sensory information related to touch

occipital lobes

Portion of the cerebral cortex lying at the back of the head, primarily responsible for processing visual information

temporal lobes

Portion of the cerebral cortex lying roughly above the ears, involved in processing auditory information and are also important for memory and speech.

motor cortex

An area at the rear of the frontal lobes that is responsible for the planning, control, and execution of voluntary movements.

sensory cortex (somatosensory cortex)

Area at the front of the parietal lobes that is responsible for processing sensory information such as touch, temperature, and pain

association areas

Areas of the cerebral cortex that are involved in higher mental functions like learning, remembering, thinking, and speaking

aphasia

Impairment of language

brocas area

Region in the frontal lobe that controls language expression (production)

wernickes area

Region in the temporal lobe that controls language reception (Understanding)

plasticity

The brain's ability to change, especially during childhood, by reorganizing after damage or by building new neural pathways based on experience

corpus callosum

The large band of neural fibers connecting the two brain hemispheres and carrying messages between them

split brain

A condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them

refractory period

In neural processing, a brief resting pause that occurs after a neuron has fired.

all or none principle

A neuron's reaction of either firing (with a full-strength response) or not firing at all.

agonists

A molecule that INCREASES a neurotransmitter's action

antagonist

A molecule that inhibits or BLOCKS a neurotransmitter's action

hippocampus

A neural center located in the limbic system that is associated with memory formation and spatial navigation.

acetylcholine (ACh)

A neurotransmitter that enables learning and memory and also triggers muscle movement

adoption study

A research design that investigates the relationships among genetic and environmental factors in the development of personality, behavior, or disorder by comparing the similarities of biological parent-child pairs with those of adoptive parent-child pairs

adrenaline

A hormone that can trigger fight or flight and increase heart rate, breathing, etc.

contralateral hemispheric organization

Each hemisphere is mainly responsible for the information of the opposite side of the body.

cortex specialization

The tendency for one side or area of the brain to carry out specific brain activities. Even though both sides of the brain are almost identical, one hemisphere primarily carries out some functions over others.

depolarization

Neurons start polarized (charged positively or negatively) and must be brought to balance so they can fire.

dopamine

A neurotransmitter associated with movement, attention and learning and the brain's pleasure and reward system.

eugenics

A much-criticized nineteenth-century movement that proposed measuring human traits and using the results to encourage only smart and fit people to reproduce

excitatory

The function of a neurotransmitter which results in a greater likelihood of an action potential.

executive function

Higher level cognitive processes of planning, decision making, problem solving, action sequencing, task assignment and organization, effortful and persistent goal pursuit, inhibition of competing impulses, flexibility in goal selection, and goal-conflict resolution.

family study

Research conducted among siblings, parents, or children to assess evidence for genetic links for characteristics or outcomes, often related to health or disease.

GABA

Most abundant inhibitory neurotransmitter; regulates daily sleep-wake cycles.

genetic predisposition

Being more likely to carry certain traits in your genetic makeup, including physical and mental conditions and disorders.

ghrelin

A hunger-arousing hormone secreted by an empty stomach

glutamate

A major excitatory neurotransmitter; involved in memory.

heredity

The transmission of traits from parents to their offspring.

inhibitory

The function of a naturally occurring chemical which results in a reduced likelihood of an action potential.

left hemisphere

Controls the facial muscles that allow us to produce speech, and enables us to understand spoken word.

leptin

A hunger-suppressing hormone secreted by a full stomach

melatonin

A hormone that helps with the regulation of the sleep-wake cycle.

multiple sclerosis

A disease due to the breakdown of the myelin sheath. Communication to muscles and brain regions slow, resulting in diminished muscle control and sometimes impaired cognition.

myasthenia gravis

A neuromuscular disease in which the muscles cannot contract, resulting in muscle weakness, difficulties with muscle control, or paralysis.

natural selection

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

nature

Genetically determined characteristics and behaviors of an individual

neural transmission

The sending of a chemical or electrical message through the neuron/neural network

norepinephrine

A neurotransmitter that helps control alertness and arousal.

nurture

Environmental factors that influence the development and behavior of a person

oxytocin

A hormone that creates positive feelings, helps with bonding, and facilitates childbirth

prefrontal cortex

Located at the very front of the brain and is responsible for complex behaviors, decision making, and moderating social behavior.

reflex arc

A neural circuit that is involved in a self-regulated response between the central and peripheral nervous systems.

resting potential

The state of a neuron when it's not being stimulated or sending signals.

reuptake inhibitor

Substance that interferes with the transport of released neurotransmitter molecules back into the presynaptic terminal, boosting the effects of that neurotransmitter.

right hemisphere

The part of the brain that controls muscles on left side of body, enables us to recognize faces and the emotion in facial expressions, and helps our ability to manipulate 2-D and 3-D environments.

serotonin

A neurotransmitter that affects hunger, sleep, arousal, and mood.

substance p

A neurotransmitter involved in pain perception and immune response.

threshold

The level of stimulation required to trigger a neural impulse.

twin study

Research with the purpose of assessing the relative contributions of heredity and environment to some attribute. Characteristics of identical and fraternal twins and comparing twins of both types who have been reared together or reared apart.

positive eugenics

Encouraging people who have "desirable" traits to reproduce

negative eugenics

Discouraging people who are seen as having "less desirable traits" from reproducing.

agonist

Mimics a neurotransmitter AT the receptor site.

antagonist

Fits in/blocks receptor sites. Does NOT mimic. Blocks the neurotransmitter.

reuptake inhibitor

Blocks reuptake and forces neuron to use excess chemical.

stimulant

Increases/speeds up neural activity.

depressant

Decreases/slows down neural activity

hallucinogen

Distorts perception and/or cognition

opioids

Relieves Pain, Very addictive

tolerance

The more a person uses a substance, the more they need to keep achieving the same high

withdrawal

When someone is actively using and then attempts to stop, they often experience terrible symptoms

dependence

Feeling the incessant need for a substance.