Chapter 3: Biopsychology Key Terms

Action potential

Electrical signal that moves down the neuron’s axon.

Adrenal gland

Sits atop our kidneys and secretes hormones involved in the stress response.

Agonist drug

Drug that mimics or strengthens the effects of a neurotransmitter.

All-or-none

Phenomenon that an incoming signal from another neuron is either sufficient or insufficient to reach the threshold of excitation.

Allele

Specific version of a gene.

Amygdala

Structure in the limbic system involved in our experience of emotion and tying emotional meaning to our memories.

Antagonist

Drug that blocks or impedes the normal activity of a given neurotransmitter.

Auditory cortex

Strip of cortex in the temporal lobe responsible for processing auditory information.

Autonomic nervous system

Controls our internal organs and glands.

Axon

Major extension of the soma.

Biological perspective

View that psychological disorders like depression and schizophrenia are associated with imbalances in one or more neurotransmitter systems.

Broca’s area

Region in the left hemisphere essential for language production.

Central nervous system (CNS)

Brain and spinal cord.

Cerebellum

Hindbrain structure that controls balance, coordination, movement, and motor skills; important in processing some types of memory.

Cerebral cortex

Surface of the brain associated with our highest mental capabilities.

Chromosome

Long strand of genetic information.

Computerized tomography (CT) scan

Imaging technique that coordinates and integrates multiple x-rays of a given area.

Corpus callosum

Thick band of neural fibers connecting the brain’s two hemispheres.

Dendrite

Branch-like extension of the soma that receives incoming signals from other neurons.

Deoxyribonucleic acid (DNA)

Helix-shaped molecule made of nucleotide base pairs.

Diabetes

Disease related to insufficient insulin production.

Dominant allele

Allele whose phenotype will be expressed in an individual that possesses that allele.

Electroencephalography (EEG)

Recording the electrical activity of the brain via electrodes on the scalp.

Endocrine system

Series of glands that produce chemical substances known as hormones.

Epigenetics

Study of gene-environment interactions, such as how the same genotype leads to different phenotypes.

Fight or flight response

Activation of the sympathetic division of the autonomic nervous system, allowing access to energy reserves and heightened sensory capacity.

Forebrain

Largest part of the brain, containing the cerebral cortex, thalamus, and limbic system.

Fraternal twins

Twins who develop from two different eggs fertilized by different sperm.

Frontal lobe

Part of the cerebral cortex involved in reasoning, motor control, emotion, and language.

Functional magnetic resonance imaging (fMRI)

MRI that shows changes in metabolic activity over time.

Gene

Sequence of DNA that controls or partially controls physical characteristics.

Genetic environmental correlation

View of gene-environment interaction asserting our genes affect our environment and vice versa.

Glial cell

Nervous system cell that provides physical and metabolic support to neurons.

Gonad

Secretes sexual hormones important for reproduction and mediating sexual motivation and behavior.

Gyrus (plural gyri)

Bump or ridge on the cerebral cortex.

Hemisphere

Left or right half of the brain.

Heterozygous

Consisting of two different alleles.

Hindbrain

Division of the brain containing the medulla, pons, and cerebellum.

Hippocampus

Structure in the temporal lobe associated with learning and memory.

Homeostasis

State of equilibrium in biological conditions.

Homozygous

Consisting of two identical alleles.

Hormone

Chemical messenger released by endocrine glands.

Hypothalamus

Forebrain structure that regulates sexual motivation and homeostatic processes.

Identical twins

Twins that develop from the same sperm and egg.

Lateralization

Concept that each hemisphere of the brain is associated with specialized functions.

Limbic system

Collection of structures involved in processing emotion and memory.

Longitudinal fissure

Deep groove in the brain’s cortex.

Magnetic resonance imaging (MRI)

Imaging technique using magnetic fields to produce pictures of tissue.

Medulla

Hindbrain structure that controls automated processes like breathing and heart rate.

Membrane potential

Difference in charge across the neuronal membrane.

Midbrain

Division of the brain located between the forebrain and hindbrain.

Motor cortex

Strip of cortex involved in planning and coordinating movement.

Mutation

Sudden, permanent change in a gene.

Myelin sheath

Fatty substance that insulates axons