Hockenbury Discovering Psychology 5th txtbk

long-term memory The stage of memorythat represents the long-term storage of information(p. 233).long-term potentiation A long-lasting increasein synaptic strength between two neurons(p. 263).loudness The intensity (or amplitude) of asound wave, measured in decibels (p. 102).LSD A synthetic psychedelic drug (p. 174).lymphocytes (LIMF-oh-sites) Specializedwhite blood cells that are responsible for immunedefenses (p. 506).Mmagnetic resonance imaging (MRI) Anoninvasive imaging technique that produceshighly detailed images of the body’s structuresand tissues using electromagnetic signalsgenerated by the body in response to magneticfields (p. 34).main effect Any change that can be directlyattributed to the independent or treatmentvariable after controlling for other possible influences(p. 29).maintenance rehearsal The mental or verbalrepetition of information in order tomaintain it beyond the usual 20-second durationof short-term memory (p. 236).major depression A mood disorder characterizedby extreme and persistent feelings ofdespondency, worthlessness, and hopelessness,causing impaired emotional, cognitive,behavioral, and physical functioning (p. 546).manic episode A sudden, rapidly escalatingemotional state characterized by extreme euphoria,excitement, physical energy, and rapidthoughts and speech (p. 549).manifest content In Freud’s psychoanalytictheory, the elements of a dream that are consciouslyexperienced and remembered by thedreamer (p. 151).marijuana A psychoactive drug derivedfrom the hemp plant (p. 175).MDMA or ecstasy Synthetic club drugthat combines stimulant and mild psychedeliceffects (p. 175).mean The sum of a set of scores in a distributiondivided by the number of scores; themean is usually the most representative measureof central tendency (p. A-5).measure of central tendency A single numberthat presents some information about the“center” of a frequency distribution (p. A-5).measure of variability A single numberthat presents information about the spread ofscores in a distribution (p. A-5).median The score that divides a frequencydistribution exactly in half so that the samenumber of scores lie on each side of it (p. A-5).meditation Any one of a number of sustainedconcentration techniques that focus attentionand heighten awareness (p. 163).medulla (meh-DOOL-uh) A hindbrainstructure that controls vital life functions suchas breathing and circulation (p. 67).melatonin (mel-ah-TONE-in) A hormonemanufactured by the pineal gland that producessleepiness (p. 139).memory The mental processes that enableus to retain and use information over time(p. 232).memory consolidation The gradual, physicalprocess of converting new long-termmemories to stable, enduring long-termmemory codes (p. 264).memory trace or engram The brainchanges associated with a particular storedmemory (p. 261).menarche (meh-NAR-kee) A female’s firstmenstrual period, which occurs during puberty(p. 394).menopause The natural cessation of menstruationand the end of reproductive capacityin women (p. 404).mental age A measurement of intelligencein which an individual’s mental level is expressedin terms of the average abilities of agiven age group (p. 294).mental image A mental representation ofobjects or events that are not physically present(p. 277).mental retardation Disorder characterizedby intellectual function that is significantlybelow average, usually defined as a measuredIQ of 70 or below, and that is caused by braininjury, disease, or a genetic disorder(p. 302).mental set The tendency to persist in solvingproblems with solutions that have workedin the past (p. 284).mere exposure effect The finding that repeatedexposure to a stimulus increases a person’spreference for that stimulus (p. 91).mescaline (MESS-kuh-lin) A psychedelicdrug derived from the peyote cactus (p. 174).meta-analysis A statistical technique thatinvolves combining and analyzing the resultsof many research studies on a specific topic inorder to identify overall trends (p. 19).midbrain The middle and smallest brain region,involved in processing auditory and visualsensory information (p. 67).middle ear The part of the ear that amplifiessound waves; consists of three small bones: thehammer, the anvil, and the stirrup (p. 102).mindfull meditation A tecnique in whichpractitioners focus awareness on present experiencewith acceptance (p. 524).Minnesota Multiphasic PersonalityInventory (MMPI) A self-report inventorythat assesses personality characteristics andpsychological disorders; used to assess bothnormal and disturbed populations (p. 449).mirror neurons A type of neuron that activatesboth when an action is performed andwhen the same action is perceived (p. 219).misinformation effect A memory-distortionphenomenon in which a person’s existingmemories can be altered if the person is exposedto misleading information (p. 254).mode The most frequently occurring scorein a distribution (p. A-5).monocular cues (moe-NOCK-you-ler)Distance or depth cues that can be processedby either eye alone (p. 119).mood congruence An encoding specificityphenomenon in which a given mood tends toevoke memories that are consistent with thatmood (p. 246).mood disorders A category of mental disordersin which significant and persistent disruptionsin mood or emotions cause impairedcognitive, behavioral, and physical functioning;also called affective disorders (p. 546).moon illusion A visual illusion involvingthe misperception that the moon is largerwhen it is on the horizon than when it is directlyoverhead (p. 125).moral reasoning The aspects of cognitivedevelopment that has to do with how an individualreasons about matters of wrong andright (p. 401).motivation The biological, emotional, cognitive,or social forces that activate and directbehavior (p. 319).motor neuron Type of neuron that signalsmuscles to relax or contract (p. 45).Müller-Lyer illusion A famous visual illusioninvolving the misperception of the identicallength of two lines, one with arrowspointed inward, one with arrows pointed outward(p. 124).myelin sheath (MY-eh-lin) A white, fattycovering wrapped around the axons of someneurons that increases their communicationspeed (p. 47).Nnarcolepsy (NAR-ko-lep-see) A sleep disordercharacterized by excessive daytime sleepinessand brief lapses into sleep throughoutthe day (p. 155).natural concept A mental category that isformed as a result of everyday experience(p. 280).natural experiment A study investigatingthe effects of a naturally occurring event onthe research participants (p. 32).Glossary G-9