Babinski reflex: A baby’s response to stroking on the bottom of the foot; when the foot is stroked, the toes fan out. 9
backward conditioning: Presenting the unconditioned stimulus before the conditioned stimulus, thereby reversing the usual order. 6
backward search: A heuristic in which a person begins at the end (or resolution) of a problem and then works backward in order to discover the steps involved. 8
basal ganglia: An area in the forebrain that coordinates fine motor activity. 3
basic anxiety: According to Karen Horney, the helplessness and insecurity a child feels when parents’ behavior is indifferent, disparaging, and erratic. 13
basic hostility: According to Karen Horney, a child’s feeling of deep resentment toward parents who arouse the child’s basic anxiety. 13
basilar membrane: An elastic membrane in the inner ear that helps transmit sound waves to the auditory nerve. 4
behavior modification: The conscious use of operant conditioning principles to change human behavior. 6
behavior therapies: The application of experimentally derived principles of learning in an attempt to change maladaptive thoughts, feelings, and behaviors. 16
behavioral genetics: The study of the relative contributions of environmental and heredity factors to differences in human thought and behavior. 2
behaviorist perspective: The view that explains behavior by asserting that environmental stimuli shape and control an individual’s actions. 1
beta waves: Rapid or high-frequency brain waves common when a person is fully awake and alert. 5
bi-directional influence: The mutual effects of parent and child on each other, as each responds to the other. 10
binocular disparity: The difference between the retinal images of the two eyes. 4
biofeedback: A specialized procedure for monitoring and controlling the physiological aspects of stress (and pain). 12
biological perspective: A view of social and personality development as guided by inherited biological tendencies. 10, 15
biomedical model: The traditional view of illness as the result of a biological malfunction that can be explained and treated without reference to the victim’s psychological state or social situation. 12
biopsychosocial approach: A multi-approach view of illness suggesting that treatment requires consideration of the biological, psychological, and social causes. It is the basis for the field of health psychology. 12
bipolar cells: Cells in the eye that are stimulated by rods or cones and in turn stimulate ganglion cells. 4
bipolar disorder: A mood disorder that involves periods of both depression and excessive elation. 15
borderline personality disorder: A personality disorder characterized by an instability of self-image, interpersonal relations, and mood. 15
bounded rationality: The theory of problem solving proposed by Nobel-prize-winning psychologist Herbert Simon. According to him, we search for a solution until we have found one that will work, even if it isn’t the best possible solution; in other words, we behave rationally, within certain constraints. 8
bulimia: An eating disorder that involves periodic bingeing alternating with purging to avoid gaining weight. 12