psych 5-6

• neuroplasticity


  the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience.
• lesion [LEE-zhuhn]


  tissue destruction. Brain lesions may occur naturally (from disease or trauma), during surgery, or experimentally (using electrodes to destroy brain cells).
• hindbrain


  consists of the medulla, pons, and cerebellum; directs essential survival functions, such as breathing, sleeping, and wakefulness, as well as coordination and balance.
• midbrain


  found atop the brainstem; connects the hindbrain with the forebrain, controls some motor movement, and transmits auditory and visual information.
• forebrain


  consists of the cerebral cortex, thalamus, and hypothalamus; manages complex cognitive activities, sensory and associative functions, and voluntary motor activities.
• brainstem


  the central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions.
• medulla [muh-DUL-uh]


  the hindbrain structure that is the brainstem's base; controls heartbeat and breathing.
• thalamus [THAL-uh-muss]


  the forebrain's sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla.
• reticular formation


  a nerve network that travels through the brainstem into the thalamus; it filters information and plays an important role in controlling arousal.
• cerebellum [sehr-uh- BELL-um]


  the hindbrain's "little brain" at the rear of the brainstem; its functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory.
• limbic system


  neural system located mostly in the forebrain — below the cerebral hemispheres — that includes the amygdala, hypothalamus, hippocampus, thalamus, and pituitary gland; associated with emotions and drives.
• amygdala [uh-MIG-duh-la]


  two lima-bean-sized neural clusters in the limbic system; linked to emotion.
• hypothalamus [hi-po-THAL- uh-muss]


  a limbic system neural structure lying below (hypo) the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system, and is linked to emotion and reward.
• hippocampus


  a neural center in the limbic system that helps process explicit (conscious) memories — of facts and events — for storage.
• cerebral [seh-REE-bruhl] cortex


  the intricate fabric of interconnected neural cells covering the forebrain's cerebral hemispheres; the body's ultimate control and information-processing center.
• frontal lobes


  the portion of the cerebral cortex lying just behind the forehead. They enable linguistic processing, muscle movements, higher- order thinking, and executive functioning (such as making plans and judgments).
• parietal [puh-RYE-uh-tuhl] lobes


  the portion of the cerebral cortex lying at the top of the head and toward the rear; it receives sensory input for touch and body position.
• occipital [ahk-SIP-uh-tuhl] lobes


  the portion of the cerebral cortex lying at the back of the head; it includes areas that receive information from the visual fields.
• temporal lobes


  the portion of the cerebral cortex lying roughly above the ears; it includes the auditory areas, each of which receives information primarily from the opposite ear. They also enable language processing.
• motor cortex


  a cerebral cortex area at the rear of the frontal lobes that controls voluntary movements.
• somatosensory cortex


  a cerebral cortex area at the front of the parietal lobes that registers and processes body touch and movement sensations.
• association areas


  areas of the cerebral cortex that are not involved in primary motor or sensory functions, but rather are involved in higher mental functions such as learning, remembering, thinking, and speaking.
• neurogenesis


  the formation of new neurons.
• corpus callosum [KOR-pus kah-LOW-sum]


  the large band of neural fibers connecting the two brain hemispheres and carrying messages between them.
• split brain


  a condition resulting from surgery that separates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them.
• consciousness


  our subjective awareness of ourselves and our environment.
• cognitive neuroscience


  the interdisciplinary study of the brain activity linked with cognition (thinking, knowing, remembering, and communicating).
• dual processing


  the principle that information is often simultaneously processed on separate conscious and unconscious tracks.
• blindsight


  a condition in which a person can respond to a visual stimulus without consciously experiencing it.
• parallel processing


  processing multiple aspects of a stimulus or problem simultaneously.
• sequential processing


  processing one aspect of a stimulus or problem at a time; generally used to process new information or to solve difficult problems.
• sleep


  a periodic, natural loss of consciousness — as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation. (Adapted from Dement, 1999.)
• circadian [ser-KAY-dee-an] rhythm


  our biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle.
• REM sleep


  rapid eye movement sleep; a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active. (Sometimes called R sleep.)
• alpha waves


  the relatively slow brain waves of a relaxed, awake state.
• NREM sleep


  non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep.
• hallucinations


  false sensory experiences, such as seeing something in the absence of an external visual stimulus.
• hypnagogic sensations


  bizarre experiences, such as jerking or a feeling of falling or floating weightlessly, while transitioning to sleep. (Also called hypnic sensations.)
• delta waves


  the large, slow brain waves associated with deep sleep.
• suprachiasmatic nucleus (SCN)


  a pair of cell clusters in the hypothalamus that controls circadian rhythm. In response to light, the SCN adjusts melatonin production, thus modifying our feelings of sleepiness.