▼RAPID REVIEW CHP.1 HISTORY AND RESEARCH Psychology is the scientific study of behavior and mental processes. The goals of psychology are to describe, explain, predict, and control the behaviors and mental process of both humans and animals. Wilhelm Wundt established the first psychology laboratory in Germany in 1879, using the method of objective introspection in an attempt to study human thought processes. Edward Titchener, a student of Wundt’s, expanded Wundt’s ideas and brought the method of introspection to the United States, calling his approach structuralism. William James was focused on discovering how our mental processes help us to function in our daily lives and began to promote his viewpoint known as functionalism. Gestalt psychologists were studying how sensation and perception create a pattern that is greater than the sum of the individual components. Sigmund Freud developed his theory of psychoanalysis, assigning a primary role to the unconscious. John Watson expanded the findings of Russian physiologist Ivan Pavlov, to promote the perspective of behaviorism. Today eight major perspectives make up the field of psychology: psychodynamic, behavioral, humanistic, biological, cognitive, sociocultural, biopsychosocial, and evolutionary. The field of psychology offers a range of professional opportunities, many based on direct practice. For example, psychiatrists, psychoanalysts, and psychiatric social workers provide varying forms of mental health care with varying specializations and training. Psychologists might also perform clinical work, but can specialize in many other areas and work in many different settings. Psychologists, like all scientists, use the scientific method. Specific research techniques include naturalistic observation, participant observation, case studies, surveys, and strategies that take a correlational approach. In an experiment, the researcher manipulates an independent variable and measures some response from the participants on the dependent variable. In order to accomplish this, the researcher usually observes two groups: an experimental group and a control group. The researcher will most likely use random assignment to determine which participants will go into which group. Often, the control group receives a bogus treatment in order to control for the placebo effect. Normally, the participants are not told which group they are in (single-blind study). In order to control for any expectations the experimenter might have (the experimenter effect) the study might be designed so that neither the participants nor the experimenter know who is in which group (double-blind study). Relying on the scientific method can help foster a more general attitude of critical thinking. ▼RAPID REVIEW CHP.2 BIOLOGICAL The nervous system is composed of a complex network of cells throughout the body. The cells in the nervous system that carry information are called neurons. Information enters at the dendrites, flows through the cell body (or soma) and down the axon. Although neurons are the cells that carry the information, most of the nervous system consists of glial cells, that provide food, support, and insulation to the neuron cells. The insulation around the neuron is called myelin and works in a way similar to the plastic coating on an electrical wire. Bundles of myelincoated axons are wrapped together in cable-like structures called nerves. The movement of an electrical signal across a neuron is called an action potential. A neuron fires in an all-or-none manner: The neuron either has an action potential or it does not. When the electrical signal travels down the axon and reaches the other end of the neuron called the axon terminal, it causes the neurotransmitters in the synaptic vesicles to be released into the fluid-filled synapse between the two cells. The central nervous system (CNS) is made up of the brain and the spinal cord. Afferent (sensory) neurons send information from the senses to the spinal cord, whereas efferent (motor) neurons send commands from the spinal cord to the muscles. Interneurons connect sensory and motor neurons and help to coordinate the signals. The peripheral nervous system (PNS) is made up of all the nerves and neurons that are NOT in the brain or spinal cord, and is divided into two parts — the somatic nervous system and the autonomic nervous system. The autonomic nervous system is in turn divided into two parts: the sympathetic division and the parasympathetic division. Two techniques used to study the brain involve either destroying a specific area of the brain (lesioning) or stimulating a specific brain area (electrical stimulation of the brain or ESB) to see the effect. Researchers have developed several methods to observe the structure and activity of a living brain, such as CT scan, MRI, EEG, PET, fMRI, or TMS. The brain can be roughly divided into three sections: the forebrain, the midbrain, and the hindbrain. The many structures within each division are discussed, such as the brainstem, medulla, reticular formation, limbic system, thalamus, hypothalamus, hippocampus, amygdala, cortex, cerebral hemispheres, corpus callosum, occipital lobes, parietal lobes, temporal lobes, and frontal lobes. Association areas are the areas within each of the lobes that are responsible for ―making sense‖ of all the incoming information. Broca’s area is located in the left frontal lobe and Wernicke’s area is located in the left temporal lobe; both play a role in language. The cerebrum is made up of the two cerebral hemispheres and the structures connecting them. Split-brain research helped scientists understand that the two cerebral hemispheres are not identical. The endocrine glands represent a second communication system in the body. The endocrine glands secrete chemicals called hormones directly into the bloodstream. The pituitary gland is located in the brain and secretes the hormones that control milk production, salt levels, and the activity of other glands. The pineal gland is also located in the brain and regulates the sleep cycle through the secretion of melatonin. The thyroid gland is located in the neck and releases a hormone that regulates metabolism. The pancreas controls the level of blood sugar in the body, whereas the gonad sex glands—called the ovaries in females and the testes in males — regulate sexual behavior and reproduction. The adrenal glands play a critical role in regulating the body’s response to stress. Mirror neurons, neurons that fire when we perform an action and also when we see someone else perform that action, may explain a great deal of the social learning that takes place in humans from infancy on. ▼RAPID REVIEW CHP.3 SENSATION AND PERCEPTION Sensation allows us to receive information from the world around us. External stimuli activate sensory receptors which convert the stimulus into an electrochemical message that our nervous system can understand. This process is called sensory transduction. Ernst Weber and Gustav Fechner were two pioneers in the study of sensory thresholds. Weber studied the smallest difference between two stimuli that a person could detect 50 percent of the time; the just noticeable difference (jnd). Fechner investigated the lowest level of a stimulus that a person could detect 50 percent of the time; the absolute threshold. Habituation and sensory adaptation are two methods our body uses to ignore unchanging information. There are three psychological aspects to our experience of light: Brightness, color, and saturation. Light travels through the vitreous humor in the middle of the eyeball to reach the retina. The eye contains two types of sensory receptors, rods and cones. The place where the information from the rods and cones leaves the eye is called the blind spot because there are no visual receptors there to receive information. The trichromatic theory and the opponentprocess theory are two account of how color vision works. Our sense of hearing is activated by the vibrations of molecules in the air. We respond to three features of sound waves: pitch, volume, and timbre. Sound waves enter our auditory system through the pinna, travel down the auditory canal, and then vibrate the eardrum which causes the hammer, anvil, and stirrup to vibrate. The vibrations of the stirrup cause the oval window to move back and forth which causes the fluid in the cochlea to vibrate. The fluid causes the basilar membrane to vibrate which causes the organ of Corti to move up, and this causes the hair cells to bend. The hair cells are the sensory receptors of the auditory system, and the movement of the hair cells triggers an action potential. There are three theories that explain how the brain receives information about pitch: place theory, frequency theory, and the volley principle. The sense of taste, or gustation, is activated by chemicals that dissolve in the mouth. The sense of smell, or olfaction, is also a chemical sense. The sense of touch is actually composed of several sensations and is more accurately referred to as the somesthetic senses; skin, kinesthetic, and vestibular. The skin contains at least six different types of sensory receptors and transmits information about touch, pressure, temperature, and pain. The currently accepted theory about pain is called gate-control theory and suggests that pain information is regulated by a number of factors in the brain and spinal cord. Perception is the interpretation of sensation and seems to follow some basic principles, such as perceptual constancies in size, shape, and brightness. Gestalt psychologists hold that people interpret information according to certain expected patterns or rules, such as figureground relationships, closure, similarity, continuity, contiguity, proximity, and common region. Depth perception appears to be present at a very early age. Visual cues for depth that require the use of one eye are referred to as monocular cues and include linear perspective, relative size, overlap or interposition, aerial perspective, texture gradient, motion parallax, and accommodation. Visual cues that use two eyes are called binocular cues and include convergence and binocular disparity. An illusion is a perception that does not correspond to reality. Perceptions can be influenced by perceptual sets or expectancies. ▼RAPID REVIEW CHP. 4 CONSCIOUSNESS Consciousness is defined as a person’s awareness of the world around him or her. Altered states of consciousness describe a shift in the quality or pattern of a person’s awareness. The sleep–wake cycle is a circadian rhythm, meaning one cycle takes about a day to complete. The cycle is regulated by the suprachiasmatic nucleus (SCN) located in the hypothalamus. Sleep deprivation results in an increase in microsleeps, concentration problems, and an inability to perform simple tasks. Sleep has been divided into two different types, rapid eye movement (REM) sleep and non-REM sleep. A large number of disorders are associated with sleep, such as sleepwalking, night terrors, insomnia, sleep apnea, and narcolepsy. Several theories have been proposed to explain why dreams occur. Sigmund Freud believed that dreams represented our unconscious thoughts and desires. He called the actual content of a dream the manifest content and the real meaning of the dream the latent content. The activationsynthesis hypothesis was originally proposed by Hobson and McCarley and suggests that dreams occur when the cerebral cortex attempts to fit together (or synthesize) random neural input from the lower brain structures. Hypnosis is a state of consciousness in which a person is especially susceptible to suggestion. One theory of hypnosis proposed by Ernst Hilgard suggests that the hypnotized person is in a state of dissociation with one part of the brain unaware of the activities happening under hypnosis and another part aware and simply watching what is happening, much like a hidden observer. The social-cognitive theory of hypnosis posits that people who are hypnotized are not in an altered state but are simply playing the role they feel is expected of them in the situation. A psychoactive drug is any drug that alters a person’s thinking, perception, or memory. Physical dependence on a drug occurs when the user’s body does not function normally without the drug. Two signs of physical dependence are drug tolerance and symptoms of withdrawal when deprived of the drug. Psychological dependence occurs when a drug is needed to maintain a feeling of emotional or psychological well-being. Psychoactive drugs can be classified into major categories including stimulants, depressants, narcotics, and hallucinogens. ▼RAPID REVIEW CHP. 5 LEARNING Learning is the process that allows us to adapt to the changing conditions of the environment. It is any relatively permanent change in behavior brought about by experience or practice. Ivan Pavlov discovered one of the simplest forms of learning called classical conditioning, and advanced our understanding of concepts such as the UCS, UCR, CS, and CR. Stimulus acquisition, stimulus generalization, stimulus discrimination, extinction, spontaneous recovery, and higher-order conditioning are other elements in classical conditioning. John Watson demonstrated conditional emotional responses with Little Albert and his learned phobia of white rats. Vicarious conditioning, conditioned taste aversions, biological preparedness, and stimulus substitution are all nuanced elements of classical conditioning that have been discovered since the initial investigations of this type of learning. Contemporary psychologists adopt the cognitive perspective, which argues that the CS must provide some information about the upcoming UCS, and that it is this expectancy that causes the association to occur. Operant conditioning is a type of learning more strongly associated with voluntary behavior and is based on Edward Thorndike’s work with cats in a puzzle box. B.F. Skinner expanded on Thorndike’s law of effect and coined the term operant conditioning for this type of learning. Reinforcement is a consequence that is pleasurable and strengthens the response that came before it. Primary reinforcers satisfy basic needs and don’t need to be learned. Secondary reinforcers get their reinforcing power through prior associations with a primary reinforcer and thus are learned. Continuous reinforcement occurs when a reinforcer is presented after every response, whereas partial reinforcement occurs when a reinforcer is given after some, but not all, of the correct responses. The timing of partial reinforcement is referred to as the schedule of reinforcement. Punishment, on the other hand, decreases the likelihood of a response. Typically punishment only temporarily suppresses the response. Shaping involves the use of operant conditioning to reward successive approximations until the desired response is obtained. Various types of behavior modification strategies have been applied to solving realworld problems. Cognitive learning theorists focus on the mental processes that occur during learning. Latent learning, learned helplessness, and insight are examples. Observational learning refers to the learning of a new behavior by observing someone else who is performing that behavior. Albert Bandura argued that four elements were needed for observational learning to occur: attention, memory, imitation, and motivation. ▼RAPID REVIEW CHP. 10 STRESS AND HEALTH Health psychology focuses on how physical activities, psychological traits, and social relationships affect overall health. Stress is the physical, emotional, cognitive, and behavioral responses to events that are perceived as threatening or challenging, and can take the form of distress or eustress. The events that cause stress are called stressors and can be either internal or external events, such as catastrophes, hassles, pressure, uncontrollability, and frustration. Conflict is another source of stress and occurs when a person feels pulled toward two or more goals but can only achieve one of them. Approach-approach conflict occurs when an individual is attempting to choose between two desirable goals. Avoidance-avoidance conflict occurs when someone must choose between two undesirable goals. Approachavoidance conflict describes a single goal that has both desirable and undesirable outcomes. An individual faced with two options in which each option has positive and negative aspects is dealing with a double approach-avoidance conflict. If there are more than two options, the conflict is called a multiple approach-avoidance conflict. Hans Selye was a pioneer in the study of the physical consequences of exposure to stressors, and proposed the general adaptation syndrome, consisting of alarm, resistance, and exhaustion phases. Researchers in the field of psychoneuroimmunology who study the effects of psychological factors on the immune system, have found that stress causes an increase in the activity of the immune system. High levels of stress have been linked to increased risk of heart disease. Also, stress can decrease the amount of natural killer cells, which are the cells responsible for fighting cancerous growths. The cognitive-mediational theory of emotions proposed by Richard Lazarus states that the way people think about and appraise a stressor is a major factor in their stress response. Primary appraisal involves estimating the severity of the stressor and classifying it as a threat, challenge, or loss, whereas secondary appraisal allows an individual to determine what resources he or she has available for dealing with the threat or loss. Type A personalities (people who are competitive, ambitious, hostile) were more likely to develop heart disease than people with a Type B personality, due primarily to the hostility dimension of the personality cluster. The Type C personality (in which people hold in their emotions and tend to be pleasant) is currently being investigated for its possible link with cancer rates. Hardy personality is associated with decreased illness due to stress. Pessimists have been found to have significantly more stress-related health problems than optimists. Social factors also play a role in the amount of stress an individual experiences. Living in poverty and job stress are two major sources of stress. A serious consequence of job stress is burnout, or negative changes in thoughts, emotions, and behaviors as a result of prolonged stress or frustration. Acculturative stress describes the stress an individual experiences when having to adapt to a new culture. The method of adaptation can affect the stress level. Some of the methods of adapting to a new culture include integration, assimilation, separation, and marginalization. The effects of negative social factors on health can be minimized by a strong social support system. Coping strategies are actions that people take to master, tolerate, reduce, or minimize the effects of stressors, and include both behavioral and psychological strategies. Problem-focused coping occurs when a person tries to eliminate the source of stress or reduce its impact by taking some action, whereas emotion-focused coping involves a person changing the way she or he feels about or reacts to a stressor. Concentrative meditation has also been found to be effective coping strategies. Culture and religion can affect an individual’s level of stress as well as the strategies used to cope with that stress.
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