Biological Bases of Behavior
central nervous system (CNS)
Division of the nervous system that consists of the brain and spinal cord
peripheral nervous system (PNS)
the sensory and motor neurons that connect the CNS to the rest of the body
somatic nervous system
division of the peripheral nervous system that control’s the body’s skeletal muscles.
a nerve cell; basic cell of the nervous system
sensory (afferent) neurons
neurons that carry information from the receptors to the spinal cord and brain
motor (efferent) neurons
neurons that carry information from the brain and spinal cord to the muscles
autonomic nervous system (ANS)
division of the peripheral nervous system involved in the control of (generally unconscious/automatic) bodily functioning through organs and glands; its sympathetic division arouses while the parasympathetic division calms
sympathetic nervous system
subdivision of the autonomic nervous system responsible for mobilizing the body in times of stress, and preparing for flight or fight
parasympathetic nervous system
subdivision of the autonomic nervous system responsible for calming the body
automatic behavior in response to a specific stimulus; does not involve communication with the brain
the oldest part and central core of the brain; responsible for automatic survival functions and composed of medulla, pons, and reticular formation.
structure of the brainstem that allows for communication between the cerebellum, cerebral cortex, & brain stem; has nuclei that are important for sleep and arousal
base of the brainstem; controls heartbeat & breathing
band of nerve fibers that run through the center of the brain stem; important in controlling arousal levels
structure of the hindbrain that coordinates voluntary muscular movements
wide band of neural fibers that connects the two hemispheres of the brain
a group of structures located beneath the cerebral cortex that are involved in regulating emotions and motivated behaviors
subcortical structure that relays incoming sensory information to the cerebral cortex and other parts of the brain; a.k.a “sensory switchboard”
device that monitors and records waves of electric activity within the brain; measured by electrodes placed on the scalp
positron emission tomography (PET scan)
visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task
computed tomography (CT scan)
imaging technique that involves the production of a large number of X-rays interpreted by a computer
MRI (magnetic resonance imaging)
imaging technique that involves the use of radio waves and a strong magnetic field to produce a signal that can be interpreted by computer
short, branchlike structures of a neuron that receive information from receptors and other neurons
technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans; capable of showing BOTH structure and function of the brain
cell body of a neuron
part of a neuron tha transmits information to other neurons and to muscles and glands
fatty protein substance that covers some axons, increasing speed of transmission
chemical messengers that cross the synaptic gap between neurons
site where two or more neurons interact but do not touch
method of clearing a neurotransmitter from the synaptic cleft, in which the neurotransmitter is reabsorbed into the terminal buttons
small pockets or sacs located in terminal buttons that contain a neurotransmitter
a molecule (e.g., drug) that enhances the operation of a neurotransmitter
a molecule (e.g., drug) that blocks or inhibits the operation of a neurotransmitter
“morphine within”; natural, opiate-like neurotransmitters linked to pain control and to pleasure
electrical charge (negative) of a neuron when it is not firing
brief electrial charge that travels down the axon; a process also called “depolarization”
the level of stimulation required to trigger a neural impulse
period, after firing, during which the neuron is unable to fire because it is repolarizing
loss of ability to speak or understand written or spoken language
the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream
chemicals produced by the glands of the endocrine system that are carried by the bloodstream to other body tissues
gland located below the thalamus and hypothalamus; called the “master gland” of the endocrine system because it controls many other glands
branch of psychology concerned with the links between biology and behavior
a neurotransmitter that enables muscle action, learning and memory; an undersupply is linked with Alzheimer’s disease
a neurotransmitter that influences movement, learning and attention; overactivity of receptors linked to schizophrenia while an undersupply linked to Parkinson’s disease
a neurotransmitter that affects mood, hunger, sleep, and arousal. An undersupply of this neurotransmitter is linked with depression.
a neurotransmitter that controls alertness and arousal; undersupply can depress mood
a major inhibitory neurotransmitter; undersupply linked to seizures, tremors, and insomnia
a major excitatory neurotransmitter; oversupply can overstimulate brain, producing migraines or seizures
bundled axons that form neural “cables” connecting the CNS to the rest of the body
central nervous system neurons that internally communicate and intervene between sensory inputs and motor outputs
brain destruction; can be naturally caused or created for experimentation
structure in the limbic system important in processing memories
structure in the limbic system responsible for directing several maintenance activities (eating, drinking, body temp); helps govern endocrine system via the pituitary gland
responsible for discovering the area on the left frontal lobe responsible for coordinating muscle movements involved in spoken language
discovered a brain area responsible for interpreting meaning of language
process of neural firing; when action potential is generated and the neuron briefly takes on a positive charge
neuron will only fire (if threshold is reached) OR not fire (if stimulation is insufficient)
the two almond-shaped nerve clusters in the limbic system believed to be responsible for fear and aggressive responses
wrinkled, gray covering of the brain that accounts for 80% of brain weight is responsible for complex processing of information, planning, learning, memory storage, etc.
famous case study in neuroscience; sustained catastrophic damage to his frontal lobes
located on the rear of the frontal lobes; responsible for directing voluntary movement on the opposite side of the body
located on the front of the parietal lobes; registers and processes body touch and movement sensations
portion of the cerebral cortex at the “back” of the head; contains the visual cortex
portion of the cerebral cortex located on the “sides” of the brain lying roughly above the ears; includes auditory areas, each receiving information primarily from the opposite ear
Roger Sperry & Michael Gazzaniga
studied split brain patients
early, misguided attempt at studying the functions of parts of the brain; held that bumps on the skull revealed the person’s personality traits
early comparative brain anatomist; developed phrenology
area (usually in the left frontal lobe) that directs the muscle movements involved in speech
brain area involved in language comprehension; usually in left temporal lobe
Areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking
transforms visual representations into an auditory code; damage to this leaves the person unable to speak and understand, but able to read
Brain’s ability to reorganize and change its structure and function throughout the life span, in reponse to injury or new learning
Traumatic Brain Injury (TBI)
blow to head or a penetrating head injury that damages brain
This is also called lateralization; refers to the fact that the left and right hemispheres of the brain have some specific functions that exist only in those hemispheres.
The left hemisphere controls the right side of the body and the right hemisphere controls the left side.
the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the central and peripheral nervous systems.
A pair of endocrine glands that sit just above the kidneys and secrete hormones that help arouse the body in times of stress.
Portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position.
glial cells (glia)
Cells in the nervous system that support, nourish, and protect neurons.
the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments
formation of new neurons
A condition in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them
Awareness of ourselves and our environment
The interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language).
The principle that information is often simultaneously processed on separate conscious and unconscious tracks; also known as “parallel processing”
a progressive disease of the nervous system that involves a degeneration of the myelin that surrounds nerve fibers in the brain and spinal cor
Assess hereditary influence by examining the resemblance between adopted children and both their biological and their adoptive parents.
the study of the relative power and limits of genetic and environmental influences on behavior
English natural scientist who formulated a theory of evolution by natural selection
Threadlike, gene-carrying structures found in a cell’s nucleus (46 in body cells; 23 in sex cells). Each chromosome consists of one very long DNA molecule and associated proteins.
The percentage of cases where both twins share the same trait or disorder
Russian geneticist who, through artificial selection, bred tame foxes
DNA (deoxyribonucleic acid)
a complex molecule containing the genetic information that makes up chromosomes
study of how the environment can alter gene expression or function (e.g. light, nutrition, temperature, presence of other species); example of interaction of nature & nurture
The study of the evolution of behavior and the mind, using principles of natural selection.
Twins who develop from separate eggs; dizygotic (DZ) twins. They are genetically no closer than brothers and sisters, but they share a fetal environment.
biochemical units of heredity that make up the chromosomes; a segment of DNA capable of synthesizing a protein
All the genetic information in an organism; all of an organism’s chromosomes.
the proportion of variation among individuals that is related to genetic variation; estimates may vary depending on the range of populations and environments studied
Also known as monozygotic (MZ) twins; twins who develop from a single fertilized egg that splits in two, resulting in two individuals that share the exact same DNA.
the subfield of biology that studies the molecular structure and function of genes
A random error in gene replication that leads to a change in nucleotide sequence.
A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
the “letters” of the DNA alphabet; they appear in pairs on the DNA molecule
U of M researcher who studied identical twins separated at birth
A hormone produced by the adrenal glands that has a vital role in the function of the sympathetic nervous system (and its “fight or flight” response). Also sometimes referred to as a neurotransmitter.
the front-most portion of the frontal lobes; involved in planning and reasoning; one of the last areas of the brain to mature (and sometimes used to explain adolescents’ relative lack of impulse control).