CHPT 3 Biopsychology

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 that mimics or strengthens the effects of a neurotransmitter.

All-or-None

Phenomenon that 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 that is 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 that is essential for language production.

Central Nervous System (CNS)

Brain and spinal cord.

Cerebellum

Hindbrain structure that controls balance, coordination, movement, and motor skills, and is involved in some memory processing.

Cerebral Cortex

Surface of the brain associated with our highest mental capabilities.

Chromosome

Long strand of genetic information.

Computerized Tomography (CT) Scan

Imaging technique in which a computer 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 that readies the body to fight or flee.

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 that our genes affect our environment and our environment influences gene expression.

Genotype

Genetic makeup of an individual.

Glial Cell

Nervous system cell providing support to neurons, including insulation and nutrient transport.

Gonad

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

Gyrus

Bump or ridge on the cerebral cortex.

Hemisphere

Left or right half of the brain.

Heterozygous

Having two different alleles.

Hindbrain

Brain division containing medulla, pons, and cerebellum.

Hippocampus

Temporal lobe structure associated with learning and memory.

Homeostasis

State of equilibrium where biological conditions are maintained at optimal levels.

Homozygous

Having two identical alleles.

Hormone

Chemical messenger released by endocrine glands.

Hypothalamus

Forebrain structure regulating sexual behavior, homeostasis, and connecting the nervous and endocrine systems.

Identical Twins

Twins that develop from the same sperm and egg.

Lateralization

Concept that each hemisphere of the brain has specialized functions.

Limbic System

Structures involved in emotion and memory processing.

Longitudinal Fissure

Deep groove separating the brain's two hemispheres.

Magnetic Resonance Imaging (MRI)

Uses magnetic fields to produce images of brain tissue.

Medulla

Controls automatic processes like breathing and heart rate.

Membrane Potential

Difference in electrical charge across a neuron's membrane.

Midbrain

Between forebrain and hindbrain; contains reticular formation.

Motor Cortex

Involved in planning and coordinating movement.

Mutation

Sudden, permanent change in a gene.

Myelin Sheath

Fatty insulation around axons.

Nervous System

Network of neurons controlling thoughts, responses, and movements.

Neuron

Information-processing cell in the nervous system.

Neuroplasticity

Nervous system's ability to adapt and change.

Neurotransmitter

Chemical messenger of the nervous system.

Nodes of Ranvier

Gaps in the myelin sheath along the axon.

Occipital Lobe

Processes visual information.

Pancreas

Secretes hormones regulating blood sugar.

Parasympathetic Nervous System

Controls routine body functions.

Parietal Lobe

Processes sensory input; contains somatosensory cortex.

Peripheral Nervous System (PNS)

Connects the CNS to the rest of the body.

Phenotype

Observable physical traits.

Pituitary Gland

Regulates other endocrine glands and fluid balance.

Polygenic

Trait influenced by multiple genes.

Pons

Connects brain and spinal cord; regulates sleep activity.

Positron Emission Tomography (PET) Scan

Tracks brain activity via radioactive injection.

Prefrontal Cortex

Responsible for higher cognitive functions.

Psychotropic Medication

Medications that adjust neurotransmitter levels to treat psychiatric symptoms.

Range of Reaction

Genes set limits; environment influences where traits fall within them.

Receptor

Protein where neurotransmitters bind on a cell's surface.

Recessive Allele

Expressed only when homozygous.

Resting Potential

Neuron's membrane potential between signals.

Reticular Formation

Regulates sleep/wake cycle and alertness.

Reuptake

Neurotransmitter reabsorption by the neuron that released it.

Semipermeable Membrane

Allows some molecules to pass, blocks others.

Soma

Cell body of the neuron.

Somatic Nervous System

Relays sensory and motor info to/from CNS.

Somatosensory Cortex

Processes touch, temperature, and pain.

Substantia Nigra

Produces dopamine; involved in movement.

Sulcus

Groove in the cerebral cortex.

Sympathetic Nervous System

Activates stress response.

Synaptic Cleft

Gap between neurons where neurotransmitters travel.

Synaptic Vesicle

Stores neurotransmitters.

Temporal Lobe

Processes hearing, memory, emotion, and some language.

Terminal Button

Axon ending containing neurotransmitter vesicles.

Thalamus

Relays sensory signals to the cortex.

Theory of Evolution by Natural Selection

Organisms better suited to their environment are more likely to survive and reproduce.

Threshold of Excitation

Level needed for a neuron to activate.

Thyroid

Regulates growth, metabolism, and appetite.

Ventral Tegmental Area (VTA)

Dopamine-producing area involved in mood and reward.

Wernicke's Area

Critical for understanding speech.