BIOLOGICAL BASES OF BEHAVIOR Flashcards
Absolute refractory period
The period during which a neuron lies dormant after an action potential has been completed.
Acetylcholine
A neurotransmitter involved in muscle movement, attention, arousal, memory, and emotion.
Action potential
A short-lived change in electric charge inside a neuron.
Adrenal cortex
The outer part of the adrenal glands, which secretes corticosteroids.
Adrenal medulla
inner part of the adrenal glands, which secretes catecholamines.
Adrenocorticotropic hormone (ACTH)
A hormone released by the pituitary gland that stimulates release of corticosteroids from the adrenal cortex.
Afferent nerves
Bundles of axons that carry information from muscles and sense organs to the central nervous system.
Agonists
Chemicals that mimic the action of a particular neurotransmitter.
All-or-none law
States that neurons fire to generate an action potential only if stimulation reaches a minimum threshold.
Amygdala
A part of the limbic system of the brain that is involved in regulating aggression and emotions, particularly fear.
Antagonists
Chemicals that block the action of a particular neurotransmitter.
Atherosclerosis
Hardening of arteries because of cholesterol deposits.
Autonomic nervous system
The part of the peripheral nervous system connected to the heart, blood vessels, glands, and smooth muscles.
Axon
A long thin fiber that transmits signals away from the soma of the presynaptic neuron to other postsynaptic neurons, or to muscles or glands.
Blood-brain barrier
A membrane that lets some substances from the blood into the brain but keeps out others.
Brain
The main organ in the nervous system.
Broca’s area
A part of the brain, in the left frontal lobe, that is involved in speech production.
Catecholamines
Hormones released by the adrenal medulla in response to stress.
Central nervous system
The part of the nervous system that includes the brain and the spinal cord.
Cerebellum
A part of the hindbrain that controls balance and coordination of movement.
Cerebrospinal fluid
The fluid that cushions and nourishes the brain.
Cerebrum
The largest part of the brain, involved in abstract thought and learning.
Chromosomes
Thin strands of DNA that contain genes.
Computerized tomography (CT)
A method for studying the brain that involves taking x-rays of the brain from different angles.
Corpus callosum
A band of fibers that divides the cerebrum into two halves.
Corticosteroids
Hormones released by the adrenal cortex in response to stress.
Dendrite
Feeler like structures that receive info from the presynaptic neuron and sends it toward the cell body of the postsynaptic neuron.
Dendritic trees
Highly branched fibers extending from neurons.
Diabetes
A condition caused by a deficiency of insulin.
Dopamine
A neurotransmitter involved in voluntary movement, learning, memory, and emotion.
Efferent nerves
Bundles of axons that carry information from the central nervous system to muscles and sense organs.
Electric stimulation of the brain
An invasive method of studying the brain, in which an implanted electrode activates a particular brain structure.
Electrocardiograph (EKG)
An instrument that records the activity of the heart.
Electroencephalograph (EEG)
Electroencephalograph (EEG) - A device that records the overall electrical activity of the brain, via electrodes placed on the scalp.
Electromyograph
An instrument that records muscle activity.
Electrooculograph
An instrument that records eye movements.
Endocrine system
A network of tissues that allows the body to communicate via hormones.
Endorphins
A group of neurotransmitters involved in pain relief, pleasure, and modulating the action of other neurotransmitters.
Excitatory postsynaptic potential
A positive change in voltage that occurs when a neurotransmitter binds to an excitatory receptor site.
GABA
The main inhibitory neurotransmitter in the brain.
Genes
Segments of DNA that function as hereditary units.
Glial cells
Cells that provide structural support, nourishment, and insulation for neurons— neural “glue”.
Glucose
A simple sugar that acts as an energy source for cells.
Glutamate
The main excitatory neurotransmitter in the brain.
Hindbrain
Portion of the brain consisting of the medulla, the pons, and the cerebellum.
Hippocampus
A part of the limbic system involved in memory.
Hormones
Chemicals that are produced in glands and released into the bloodstream, involved in regulating body functions.
Hypothalamus
A part of the forebrain that helps to control the pituitary gland, the autonomic nervous system, body temperature, and biological drives.
Immune system
The body’s defense against harmful agents such as bacteria, viruses, and other foreign substances.
Inhibitory postsynaptic potential
Inhibitory postsynaptic potential - A negative change in voltage that occurs when a neurotransmitter binds to an inhibitory receptor.
Insulin
A hormone secreted by the pancreas that allows sugar to be used by cells for energy.
Ions
Positively and negatively charged atoms and molecules.
Lateralization
The difference in specialization between the two hemispheres of the brain.
Leptin
A hormone secreted by fat cells.
Limbic system
A part of the forebrain involved in emotional experience and memory.
Lobotomy
A surgical procedure that severs nerve tracts in the frontal lobe, formerly used to treat certain psychological disorders but now rarely performed.
Long-term potentiation
A lasting change at synapses that occurs when long-term memories form.
Magnetic resonance imaging (MRI)
A method for studying the brain that uses magnetic fields and radio waves to produce pictures of the brain.
Medulla
A part of the hindbrain that controls essential functions that are not under conscious control, such as breathing.
Melatonin
A hormone that regulates the sleep cycle.
Midbrain
The part of the brain between the hindbrain and forebrain that is involved in locating events in space and that contains a dopamine-releasing system of neurons.
Monoamine oxidase inhibitors (MAOIs)
A class of antidepressant drugs that increase the level of norepinephrine and serotonin.
Monogenic traits
Traits determined by a single gene.
Mutations
Small changes in genes.
Myelin sheath
The fatty coating around some axons that increases the speed of neural impulse transmission. (White matter in the brain)
Narcotics
Drugs that can relieve pain; also called opiates.
Nerves
Bundles of axons extending from many neurons.
Neurons
Nervous system cells that communicate via electrochemical signals to receive, transmit, and integrate information.
Neurotransmitters
These chemicals messangers are the chemical portion of the electrochemical communication of the nerveous system. They are released from a neuron, go across the synaptic gap, and activate another neuron.
Norepinephrine
A neurotransmitter involved in learning, memory, dreaming, awakening, emotion, and responses to stress.
Nucleotides
Biochemical units that make up DNA and genes.
Parasympathetic nervous system
Part of the autonomic nervous system that keeps the body still and conserves energy. It is active during states of relaxation.
Peripheral nervous system
The part of the nervous system outside the brain and the spinal cord that includes the somatic nervous system and the autonomic nervous system.
Pineal gland
A gland that secretes melatonin.
Pituitary
The master gland of the endocrine system, which regulates the function of many other glands.
Polygenic traits
Traits influenced by several genes.
Pons
A part of the hindbrain involved in sleeping, waking, and dreaming.
Positron emission tomography (PET)
A method for studying the brain that involves injecting a radioactive substance, which collects in active brain areas.
Postsynaptic neuron
At a synapse, the neuron that receives a neurotransmitter.
Postsynaptic potential
The voltage change that occurs at a receptor site of a postsynaptic neuron when a neurotransmitter molecule links up with a receptor molecule.
Presynaptic neuron
At a synapse, the neuron that releases a neurotransmitter.
Primary auditory cortex
In the temporal lobe of the cerebrum, the brain part involved in processing auditory information.
Primary motor cortex
In the frontal lobe of the cerebrum, the brain part involved in controlling muscle movement.
Primary somatosensory cortex
In the parietal lobe of the cerebrum, the brain part involved in handling touch-related information.
Primary visual cortex
In the occipital lobe of the cerebrum, the brain part involved in handling visual information.
Reticular formation
A structure that includes parts of the hindbrain and midbrain and that is involved in sleep, wakefulness, pain perception, breathing, and muscle reflexes.
Reuptake
The process by which neurotransmitter molecules return to presynaptic neurons.
Selective serotonin reuptake inhibitors (SSRIs)
A class of antidepressant drugs that increase the level of serotonin.
Serotonin
A neurotransmitter involved in sleep, wakefulness, appetite, aggression, impulsivity, sensory perception, temperature regulation, pain suppression, and mood.
Soma
The central area of a neuron; also called the cell body. (Gray matter in the brain)
Somatic nervous system
The part of the peripheral nervous system that is connected to the skeletal muscles and sense organs.
Split-brain surgery
A surgical operation in which the corpus callosum is cut, separating the two hemispheres of the brain.
Spinal reflexes
Automatic behaviors that require no input from the brain.
Suprachiasmatic nucleus
The main biological clock regulating circadian rhythms of sleep in humans.
Sympathetic nervous system
Part of the autonomic nervous system that prepares the body for action and expends energy.
Synapse
The junction between the axon of one neuron and the cell body or dendrite of a neighboring neuron.
Synaptic cleft
The gap between two cells at a synapse.
Synaptic vesicles
Small sacs inside a neuron’s terminal buttons, in which neurotransmitters are stored.
Terminal buttons
Bulges at the end of axons that secrete neurotransmitters.
Thalamus
The part of the brain through which almost all sensory information goes on its way to the cerebrum.
Wernicke’s area
A part of the brain, in the left temporal lobe, that is involved in understanding language.
Forebrain
The biggest and most complex part of the brain, which includes structures such as the thalamus, the hypothalamus, the limbic system, and the cerebrum.
Lobotomy
A surgical procedure that severs nerve tracts in the frontal lobe, formerly used to treat certain psychological disorders but now rarely performed.
Monoamine oxidase inhibitors (MAOIs)
Monoamine oxidase inhibitors (MAOIs) - A class of antidepressant drugs that increase the level of norepinephrine and serotonin.
Resting potential
The slight negative charge inside an inactive neuron.
Resting state
The period during which the inside of a neuron has a slightly higher concentration of negatively charged ions than the outside does. A neuron during this time is inactive.
Tricyclics
A class of antidepressant drugs that increase the level of norepinephrine and serotonin.
Lesioning studies
An invasive method of studying the brain in which a specific, small area of the brain is destroyed.
Nervous system
The body’s communication network. It handles, receives, transmits, and integrates information just as the circulatory system handles blood. This complex, highly coordinated network of tissues communicates via electrochemical signals.
Spinal cord
Connects the brain to the rest of the body.
Spinal reflexes
Automatic behaviors that require no input from the brain.
Multiple sclerosis
A myelin degeneration disease, causing loss of muscle control, etc. due to loss of transmission efficiency in the nervous system when the myelin sheaths deteriorate.
