Unit 1 Vocabulary

Psychology

The science of behavior and mental processes.

Nature-nurture issue

The longstanding controversy over the relative contributions that genes and experience make to the development of psychological traits and behaviors. Today’s science view traits and behaviors as arising from the interaction of nature and nurture.

Natural selection

The principle that the inherited traits enabling an organism to survive and reproduce in a particular environment will (in competition with other traits variations) most likely be passed on to succeeding generations.

Evolutionary psychology

The study of the evolution of behavior and the mind, using principles of natural selection.

Behavior genetics

The study of the relative power and limits of genetics and environmental influences of behavior.

Mutation

A random error in gene replication that leads to a change.

Environment

Every nongenetic influence, from prenatal nutrition to our experienced of the people and things around us.

Heredity

The genetic transfer of characteristics from parents to offspring.

Genes

The biochemical unit of heredity.

Genome

The complete instructions for making an organism.

Monozygotic Twins

Also known as identical twin, individuals who developed from a single fertilized egg that slit in two, creating two genetically identical organisms.

Dizygotic twins

Also known as fraternal twins, individuals from separate fertilized eggs. They are genetically no closer than ordinary siblings, but they shared a prenatal environment.

Interaction

The interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)

Epigenetics

“Above” or “in addition to” (epi) genetics; the study of the molecular mechanisms by which environments can influence genetic expression. (without a DNA change)

Nervous system

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

CNS

Central Nervous System - the brain and spinal cord

PNS

Peripheral Nervous System - the sensory and motor neurons that connect the CNS to the rest of the body.

Nerves

Bundled axons that form neural cables connecting the CNS with muscles, glands, and sensory organs.

Afferent neurons

Also known as sensory neurons that carry incoming information from the body’s tissue and sensory receptors to the brain and spinal cord.

Efferent neurons

Also known as motor neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.

Interneurons

Neurons within the brain and spinal cord; they communicate internally and process information between the sensory inputs and motor outputs.

Somatic Nervous System

The division of the peripheral nervous system that controls the body’s skeletal muscles. Also call the skeletal nervous system.

ANS

Autonomic Nervous System - The part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division calms.

Sympathetic Nervous System

The division of the autonomic nervous system that arouses the body, mobilizing its energy.

Parasympathetic Nervous System

The division of the autonomic nervous system that calms the body, conserving its energy.

Reflex

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

Neuron

A never cell; the basic building block of the nervous system.

Cell body

The part of a neuron that contains the nucleus; the cell’s life-support center.

Dendrites

A neuron’s often bushy, branching extensions that receives and integrate messages, conducting impulses toward the cell body.

Axon

The segmented neuron extension that passes messages through its branches to other neurons or to muscles or glands.

Myelin sheath

A fatty tissue layer segmentally encasing the axons of some neurons; it enables vastly greater transmission speed as neural impulses hop from one node to the next.

Glial cells (glia)

Cells in the nervous systems that support, nourish, and protect neurons; they may also play a role in learning, thinking, and memory

Action potential

A neural impulse: a brief electrical charge that travels down an axon.

Threshold

The level of stimulation required to trigger a neural impulse.

Refractory period

In neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potential cannot occur until the axon returns to its resting state.

All-or-none response

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

Synapse

The junction between the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at the is junction is called the synaptic gap or synaptic cleft.

Neurotransmitters

Chemical messengers that cross the synaptic gap between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

Reuptake

A neurotransmitter’s reabsorption by the sending neuron.

Endorphins

“Morphine within”; natural, opioid-like neurotransmitter linked to pain control and to pleasure.

Agonist

A molecule that increases a neurotransmitter’s action.

Antagonist

A molecule that inhibits or blocks a neurotransmitter’s action.

Endocrine system

The body’s “slow” chemical communication system; a set of glands and fat tissue that secrete hormones into the bloodstream.

Hormones

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

Psychoactive drug

A chemical substance that alters the brain, causing changes in perceptions and moods.

Substance use disorder

A disorder characterized by continued substance use despite resulting life disruption.

Depressant

Drugs that reduce neural activity and slow body functions.

Tolerance

The diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drug’s effect.

Addiction

An everyday term for compulsive substance use (and sometimes for dysfunctional behavior patterns, such as out-of-control gambling) that continue despite harmful consequences.

Withdrawal

The discomfort and distress that follow discontinuing an addictive drug or behavior.

Barbiturates

Drugs that depress central nervous systems activity, reducing anxiety but impairing memory and judgment.

Opioids

Opium and its derivatives; they depress neural activity, temporarily lessening pain and anxiety.

Stimulants

Drugs that excite neural activity and speed up body functions.

Hallucinogens

Psychedelic (“mind-manifesting”) drugs that distort perceptions and evoke sensory images in the absence of sensory input.

Near-death experience

An altered state of consciousness report after a close brush with death (such as cardiac arrest); often similar to drug-induced hallucinations.

Biological psychology

The scientific study of the links between biological and psychological processes. Some biological psychologists call themselves behavioral neuroscientists, neuropsychological, behavior genetics, physiological psychologists, or biopsychologists.

Biopsychosocial approach

An integrated approach that incorporates biological, psychological, and social-cultural levels of analysis.

Levels of analysis

The differing complementary view, from biological to psychological to social-cultural, for analyzing any given phenomenon.

Neuroplasticity

The brain’s ability to change, especially during childhood, by reorganizing after damage by building new pathway based on experience.

Lesion

Tissue destruction. Brian lesion may occur naturally (from disease or trauma), during surgery, or experimentally (using electrodes to destroy brain cells)

EEG

Electroencephalogram - an amplified recording of the waves of electrical activity sweeping across the brain’s surface. These waves are measured by electrodes placed on the scalp.

MEG

Magnetoencephalography - a brain-imaging technique that measures magnetic fields from the brain’s natural electrical activity.

CT scan

Computed tomography - A series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain’s structure.

PET

Positron emission tomography - a technique for detecting brain activity that displays where a radioactive from of glucose goes while the brain performs a given task.

MRI

Magnetic resonance imaging - a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. MRI scans show brain anatomy.

fMRI

Functional MRI - a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function as well as structure.

Hindbrain

Consists of the medulla, pons, and cerebellum; directs essential survival functions, such as breathing, sleeping and wakefulness, as well as coordination and balance.

Midbrain

Found atop the brainstem; connects the hindbrain with the forebrain, controls some motor movement, and transmits auditory and visual information.

Forebrain

Consist of the cerebral cortex, thalamus, and hypothalamus; manages complex cognitive activates, sensory and associative functions, and voluntary motor activities.

Brainstem

The central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions.

Medulla

The hindbrain structure that is the brainstem’s base; controls heartbeat and breathing.

Thalamus

The forebrain’s sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla.

Reticular formation

A nerve network that travels through the brainstem into the thalamus; it filters information and plays an important role in controlling arousal.

Cerebellum

The hindbrain’s “little brain” at the rear of the brainstem; its functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory.

Limbic system

Neural systems located mostly in the forebrain, below the cerebral hemispheres, that includes the amygdala, hypothalamus, hippocampus, thalamus, and pituitary gland; associated with emotions.

Amygdala

Two lima-bean-sized neural clusters in the limbic system; linked to emotion.

Hypothalamus

A limbic system neural structure lying below (hypo) the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system, and is linked to emotion and reward.

Hippocampus

A neural center in the limbic system that helps process explicit (conscious) memories, of facts and events, for storage.

Cerebral cortex

The intricate fabric of interconnected neural cells covering the forebrain’s cerebral hemispheres; the body’s ultimate control and information-processing center.

Frontal lobes

The portion of the cerebral cortex lying just behind the forehand. They enable linguistic processing, muscle movements, higher-order thinking, and executive functioning (such as making plans and judgments).

Parietal lobes

The portion of the cerebral cortex lying at the top of the head and toward the rear; it receives sensory input for touch and body position.

Occipital lobes

The portion of the cerebral cortex lying at the back of the head; it includes areas that receive information from the visual field.

Temporal lobes

The portion of the cerebral cortex lying roughly above the ears; it includes the auditory areas, each of which receives information primarily from the opposite ear. They also enable language processing.

Motor cortex

A cerebral cortex area at the rear of the frontal lobes that controls voluntary movement.

Somatosensory cortex

A cerebral cortex area at the front of the parietal lobes that registers and processes body touch and movement sensations.

Association areas

Areas of the cerebral cortex that are not involved in primary motor or sensory functions but rather are involved in higher mental functions such as learning, remembering, thinking, and speaking.

Neurogenesis

The formations of new neurons.

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 separates the brain’s two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them.

Consciousness

Our subjective awareness of ourselves and our environment.

Cognitive neuroscience

The interdisciplinary study of the brain activity linked with cognition (thinking, knowing, remembering, and communicating).

Dual processing

The principle that information is often simultaneously processed on separate conscious and unconscious tracks.

Blindsight

A condition in which a person can respond to a visual stimulus without consciously experiencing it.

Parallel processing

Processing multiple aspect of a stimulus or problem simultaneously.

Sequential processing

Processing one aspect of a stimulus or problem at a time; generally, use to process new information or to solve difficult problems.

Sleep

A periodic, natural loss of consciousness — as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation.

Circadian rhythm

Our biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle.

REM sleep

Rapid eye movement sleep, recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active. (Sometimes called R sleep)

Alpha waves

The relatively slow brain waves of a relaxed, awake state.

NREM sleep

Non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep.