neuropsychology t 181

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WPM~ObSV WQLOGVof the skin, known as cafk-au-lait spots, are the abnormali-ties most important in establishing the diagnosis of neurofi-bromatosis. Both first appear in childhood but increase innumber with advancing age. The soft, flesh-colored skin forms of communictumors arise anywhere along the paths of the nerves that classified but can, on occasupply the skin, and they may number in the thousands.They tend to be most numerous on the trunk of the bodyand occur infrequently on the palms or soles. They maycoalesce to form large masses, producing a grotesque ap-pearance, similar to that seen in the elephant man. Bonelesions occur in up to half of individuals with neurofibro-matosis, sometimes causing disfiguring curvature of thespine. Forty percent are either mentally retarded or have alearn ing disability.Treatment of neurofibromatosis is limited chiefly to sur- James formulated ideasgery. Sometimes it is necessary to remove tumors encroach-ing upon vital structures. In addition, attempts have beenmade to perform reconstructive surgery in people with themo re disfiguring form s of the disease.The outlook for people with neurofibromatosis is highlyvariable. Some who are severely afflicted may succumb needed to be anfrom one of the complications of the disease, such as the different from those odevelopment of cancer in the tumors. Individuals who havea minor form of the disease, however, have a normal lifeexpectancy. KENNETH. GREERNEUROBSYCHOLOGY the study of how the brainorganizes experience. Observations and experiments are car-ried out in the clinic and in the experimental laboratory.Brain tissue is electrically stimulated, electrical recordings ar emade from various sites in the brain, and/or parts of the This change in direction was consistent withbrain are resected. Observations of verbal and nonverba l iorist orient ation of psychology du rin g the mibehavior serve as indicators of the subject's experience. Studies century. Neuropsychologists, however, realizedof the effects of drugs on brain function a nd on behavior a re noring verbal behavior, scientistsalso often included in ne~ro~sychologicalxperiments. source of information. Ne uroIn t he clinic, electrical record ings from the scalp of patients showed that instrumental and ver

are regularly undertaken to determine whether any abnor- psychological processes and in tmality in the brain function exists. On the basis of the work understanding much o f what we call mental.done in experimental laboratories, it would seem that such exemplified by blirecordings ought to be don e while the patient is performing injury to the backbehavioral tasks, which place a processing load on func- Most body parts are connectedtion-that is, the recordings ought to reflect a specific mo de the opposite side-the conn ectin g nerof func tioning of the b rain. SO far, however, this sort of From the eyes the connections are so atesting is not standard procedure. Recordings are ordinarily to their term inus in the back end ofmade while the patient is daydreaming or resting or evenasleep.major area of clinical neuropsychology concerns thebehavioral competence of patients who have suffered braindamage. Chemical tracers using radioactive substances in-jected into the arteries that feed blood to the brain are usedto determine the degree of brain damage that has occurredafter a stroke or head injury. Recordings (computerized tions. Afte r all, were nontomography, or CT scans) mad e with such tracers take from having them press a panel15 minutes to a half hour, durin g which the patient is asked as observers, would (incorreto perform some prolonged activity such as reading, reciting, behavior that the animals clistening to music, or solving mathematical problems. Th e Another instance of theresults of these investigations have shown that the brain is verbal reports of patientsmade up of many systems, which differ from one another in who have had the hemfunction. T he systems are defined by the influence they exert separated for treatment ofon experience and behavior, and they ar e delineated anatom- show n to their right, thesically and by their chemical differences, objects verbally, since inHistory. As a science, neuropsycholog y is a branc h of both cultur e, speech is cexperimental psychology and clinical neurology. Psychology however, the objects arebecame a science when, toward the end of the 19th century, cannot describe the objects verbally but canit was realized that mental experience could be gauged by an appropria te picture also show n on the lestudying behavior. In humans, behavior is one of two kinds: states that he did not see the object on the


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h cho~ogy ecame recog n~z eds a separate dlsc~plrn e, d b h J T o f he 20th ce ntur y. The ea rly h ls to ry thatb&@?$#gnltion can be told in ter ms of a han dfu l of

applied the behavioralJohn B. Watson. He wasand Karl Pribram

at the rear are severed from the rest of thePribram explored changes in behavior and experienceJting from lobotomy. H e focused on nonh uman primatech, establishing an experim ental psychosurgery labo-rj; at Yale University. Pribram discovered that the psy-ds'ukgical effect of lobotom y w as d ue to the close conne ctionthe far frontal cortex with the hypothalamus and thelimbuc in Latin) of the cerebral hemispheres)well as the hypothalamus regulated visceral and endocrine

eriments led P ribra m to investigate not only th e func tionsebrain, but also other systems of the bra in that had untilbeen overlooked. In the process Prib ram and his studentsly established neuropsychology as an experim ental science.

1981 Sperry exposed

usness. B lind s~g ht s just one of the disturbances'reflective self-consciousness" result fr om inju ry to t he

a part of their body on the side opposite to theonly to be caught in the sheets. When her arm wasbe the cause of the obstructed movement, sheattached to her body she was surprised and flustered.

The arm just did not seem to belong to her. If it were aspeechless animal being observed, we would be unable tonote that anything had gone awry. The behavior of theanimal toward its environment would be essentially unim-paired. Its behavior is guided by the contents of a moreelementary form of consciousness. A cat running across thecoffee table is certainly judged conscious. If, however, one'sneighbor suddenly did the same thing and you asked himwhy, he might well reply that he did not know, that he justhad the urge to climb on the table. Only later would it bediscovered that he had been hypnotized and given thesuggestion to climb onto the coffee table. Like the cat theneighbor had acted without reflective self-consciousness,except that he had the verbal capacity to say soH v~ no si s nduces an alternate state of consciousness. Or-,dinarily we experience such alternate states when we fallasleep. Dreams that occur during sleep are difficult orimpossible to recall when we awaken. Alternate states ofconsciousness are often exclusive: what we experience in onestate becomes inaccessible when we are in another. W hen weare depressed everything seems hopeless; when we are elated,we cannot but wonder that we could ever feel anything butoptimism. Drugs that act on the brain are known to changestates of consciousness. That is why they are called "psy-choactive." A practical offshoot of neuropsychology, neuro-psychopharmacology, is ma king great strides .in relatingvarious chemical brain states to various mood states, statesof consciousness.Not only are the contents of consciousness determined bystates, but th e converse is true: pass a bakery and the smellsquickly induce an appetitive state. The connections betweenstate and content are studied by experimental and neuro-psychologists as the processes of attention. T he states and thecontents of consciousness, and the attentional processes thatconnect them, provide animals with sufficient awareness toadapt successfully to the events experienced by them duringtheir lifetime. What is the role, then, of reflective self-consciousness in the economy of being? With reflectiveconsciousness comes the search for identity, the separation ofa perceiving self from that which is perceived. With reflectiveconsciousness comes the search for communion, communionthat allows consciousness to transcend self. With reflectioncomes conscience (in French no distinction is made between"consciousness" and "conscience"). T hese asp ects of conscious-ness are hallm arks of h um an existence. But, as properties ofa physical system that is not that different in appearancefrom that of certain other animals, their emergence anddevelopment is less explicable in evolutionary terms thanmore strictly "biological" traits.Le a r n ing a nd Memory There is considerable memorystored in t he bod y: muscles ,become larger w ith practice;immune systems protect against recurrent onslaughts ofmicroorganisms; respiratory, heart rate, and digestive cyclesbecome established and entrained by experience. But in orderto remember grandmother, the high school prom, multipli-cation tables, and th e first date, a normally functioning brainis required.There are a sufficient number of brain cells to storeprodigious amounts of experience. More important, eachbrain cell is endowed with many branching nerve fibers.Most neuropsychologists believe the experience becomes storedin the junctions between the nerve fiber branches, althoughthis has not been firmly established. What is known is thatin the brains of newborns there are myriads of such connec-tions. During the lifelong learning process, some of theseconnections atrophy and disappear, others show a thickening


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of their active membranes. This indicates that connectivitybecomes more selective: when a previously experienced eventrecurs, it triggers a network of interconnected brain cells inthe same fashion as it did originally. Thus, the originalexperience is remembered. On e would expect that such asystem of connectivities could become damaged or evencleanly excised in the experimental laboratory. But this is notthe case. When individuals have strokes or when neuropsy-chologists take out chunks of brain tissue, no single isolatedmemory trace is removed. A woman who has had a strokeyet still recognizes her children does not then turn to herhusband to ask who he might be. Memory is more of awhole and this has posed a serious problem to under standing .Two discoveries enabled neuropsychologists at least tobegin an explanation. The first was the mathematical for-mulation that led to holography. A hologram stores eventsin a peculiar fashion. Instead of making an image on aphotographic film, as in ordinary photography, a hologramis composed of the nodes of intersection of various waveforms of light reflected from a scene. In such nodes theintersecting waves either reinforce or cancel each other.Mathematically the photographic image and the hologramare invertible transforms of each other, which means that animage can be transformed into a hologram and a holograminto an image.The second discovery is more of an invention than adiscovery. Scientists have found ways to mimic the connec-tivities of brain cells in com puter p rograms. Tech niques havebeen developed allowing the programs to learn any thing fromphrases of music to language. What is of special interest isthat when the programs are examined, the memory for amusical phrase or of a particular word can no t,b e located inany particular part of the network of connections. Storage isdistributed. The events to be remembered are first disrnem-bered and stored in a nonlocal fashion. Mathematicallv. thesecomputer programs are derived from the same invertibletransformations that also spawned holography. By recordingfrom sing le brain cells located in the visual system of mo nkey sand cats, scientists established that visual processing can bedescribed bv the same mathematical formulations that char-- ~acterize holography and parallel distributed processingPDP). as the comDuter simulations are called. The brainprocesses responsible for a distributed memory store can,therefore. be described bv these formulations.Experimental psychologists and neuropsychologists havedistinguished several different sorts of learning and memory.O ne is sensory memo ry, tied closely to a sensory system andlasting from a few seconds to minutes and occasionally hours.Another is skill learning and memory, which become dis-turbed when the motor systems of the brain are damaged.Reference (also called semantic) memory is the kind ofmemo ry stored in a dictionary Th e posterior systems of thebrain construct this sort of memo ry store. By con trast, .thefrontal and limbic parts of the forebrain process episodes.Memory of this s ort hangs together because it was experiencedas a unit marked at its beginning and end by an orientingreaction. This sort of memory is closely related to what iscalled workin g me mory , the type of mem ory used in everydaylife to keep track of what needs to be done.Lang uage. Hu ma ns are distinguished by their ability tocommunicate via a bevy of signals that reference their ownexperience and evoke similar experiences in others. Thenatural languages, mathem atics, and music are signals of thissort. In most hum ans raised in Western cultures the functionsof the hemispheres of their brains have specialized theprocessing of such signals. Basic to the specialization of the

functions of the hemispheres of the brain is the precedeof language development given to the left hemisphere.discover of hemisph eric specialization goes back to the ancGreeks. Hippocrates and Galen knew that damage toleft side of the brain resulted in disturbances of speechmodern times this fact was rediscovered by Paul Bralthough the brain region which, when damaged, is ressible for speech disorders lies somewhat behind theBroca thought to be critical. This region was better d hby Carl Wern icke , who also d is ti ngu ished two types o f sdisturbance. One type, named Broca's aphasia bec usresults from damage to the front of the entire region neawhere Broca had placed it, is a disturbance of expresjTh is type of aphasia (speech disturbance d ue to brain injis often characterized by telegraphic speech: only a t e

however, it becomes aptogether a meaningless ssignify anything.There are other, even more severe,more extensive brain damage. Also tspeech disturbances due to disconnections of nerve fibbetween the various brain systems responsible not onlyspeech but for what the speech signifies (its reference)the effect it is to have (itinvolved in language, the speech sythem.By studying the relation between braineuropsychologists have learned much aorganization of the brain. T he fact tof brain connection networks bywere able to learn to reproduceorganization m ust be a combinatioconstructed of networks that can oprocessors. The systems are ordistance connections, which fobetween senses and brain, brthe brain w ith one another. The PDP netwof sho rt-distance micro-conne

training and practice), the

framework within which we had organno longer serves. Reorganization can beprecipitous, as wh en we are convertedPersonality. T o each ofmeaning is mediated by prelevant to present experience. It is thare involved in processing relevance. T hconnected to others that lie within thehave many chemica

heir. But this much is already known: s


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of sensory input. In turn, the limbicis going on in the sensory and motorof the brain, thus influencing whathas a critical relation to

KARL RIBRAM.. 4=-'.> cc;*WEUROSHS or neurotic disorder, a condition of emo-maladjustment manifested by a variety of mental,d o n a l , physical, and behavioral symptoms. Whe n thern&tion is mild, organic and mental faculties are essentially

it. In more sevire cases, it can develop into an almostin&pacitatingdisturbance of thinking, feeling, and acting.Origins The traditional view of psychotherapy, stemming' .from the work of Sigmund Freud, is that neuroses, orpsgchoneuroses, arise from certain unconscious inner con-kg These conflicts may be between opposing wishes orbpween wishes and the norms of conduct established bysociety People who are unable to resolve their conflicts

nervous tension. Abnormal fatigue, unrelieved by rest andwithout any physical disorder to account for it, is anotherfrequent neurotic symptom.The most significant symptom of neurosis is anxiety. Fearof insanity, infection, venereal or heart disease, cancer, deathor suicide, people, or animals is found in many neuroticpatients. Most of the m have no overt cause for their fears, yetthey are harassed by them constantly. Anxiety is a state ofchronic fear, a distressing uneasiness of the mind over ananticipated ill, that pervades the lives of most neuroticindividuals. Attacks o f acute anxiety may occur suddenly a ndbe so intense as to develop into severe panic or terror.Treatment Psychotherapy is the psychological treatmentof emotional maladjustment, personality problems, and otherneurotic disorders. Its goal is to make the emotionallydisturbed and unstable patient a happier, more mature, andmore stable person. Psychoanalysis is an especially intensiveform of psychotherapy that employs such specialized tech-niques as free association, dream analysis, exploration offantasies, and so forth.In another form of psychological treatment, group therapy,patients are organized into small therapeutic communities, orgrou ps, with the psycho:herapist as leader. A dyna mi c rela-tionship usually develops quickly, not only between thetherapist and the group but among the group membersthemselves. The various psychodynamic factors (identifica-

tion, resistances, hostility, competitiveness, escape mecha-nisms) operative in such a setting come to the fore an d can beexplored, understood, and ultimately dealt with.A variety of tranquilizing drugs has been introduced intothe treatment of neurotically disturbed patients. Many ofthese chemicals and ':psychotropic agen ts have becom epopular an d are widely used because they have helped paiientswith disturbing symptoms to feel reasonably comfortable, towork, to sleep, or at least to function better than before. Theuse of chemical compounds is limited, however, not only bythe fact that they do not cure the basic disorder but alsobecause they may produce a variety of unwanted side effects.Conditioning therapy, a relatively recent form of treat-ment, often depends upon the patient's ability to achievecomplete physical relaxation. Conditioning therapy may in-clude negative conditioning, such as electric shock, to elimi-nate undesirable acts or habits.Classification. Citing a lack of agreement among mentalhealth professionals concerning the definition of neurosis;the iagnostic and Statistical Manual of Mental Health isordersof the Ame rican Psychiatric A ssociation (3rd ed., 1980) omitsthe class of neuroses as a separate diagnostic category. Instead,these disorders are grouped under the headings affectivedisorders (depressive neurosis), anxiety disorders (phobias,panic disorder, obsessive-compulsive disorder), somatoformdisorders (hysteria, or conversion disorder, hypochondria),dissociative disorders (psychogenic amnesia, multiple person-ality), and psychosexual disorders. See alro AMNESIA;NXIETYDISORDERS;ONVERSIONISORDER;ISSOCIATIVEISORDERS;HYPOCHONDRIA;ULTIPLE ERSONALITY;HOB IA; SYCHO-ANALYSIS;SYCHOLOGY:bnormal Psychology; PSYCHOSEXUALDISORDERS;SYCHOSIS;SYCHOTHERAPY;NCONSCIOUS.

with themselves repress them; that is, they remove them

NEUROTRANSMITTER a chemical substance pro-duced by nerve cells that transmits nerve impulses across avery nar row space, called a synaptic gap, to other cells. Someneurotransmitters may also inhibit the generation of nerveimpulses. After a transmitter has exerted its effect, it isusually destroyed by enzymes.Approximately 30 different neurotransmitters are known.

orn their consciousness so that they ar e apparently forgot-tcn But the forgotten mate rial, which consists of repressedmental processes and painful and unpleasant memories, stillkccps its dynamic force and nature. It does not remaindormant within the deeper, unconscious layers of the mind,bot exerts active pressure from within, influencing thepason's thinkin g, feeling, and behavior. Th e term neurosisk sometimes used to denote this neurotic process itself as a~ C h o l o ~ i c a lechanism that produces symptoms.number of psychiatrists reject the Freudian approach toauosis, however, insisting instead that the problem of

to a bad habit, and subjectcure by conditioning. Others attempt to explain the

Symptoms. The average personality is relatively unham-by mental conflicts, has a satisfactory working capacity,is able to love someone other than himself. Har dsh ip andare endured without excessive impairment of thedual personality. A neur otic person do es not fully answ errequirements and often fails completely in these areas.Contrary to popular belief, imagination does not play the

t important part in neurotic conditions. The frequentic and nonsoma tic com plaints of neur otic indivi duals,as anxiety, headache, dizziness, fatigue, Indigestion,not imaginary. Although not caused by any organicor lesion, they are present and real. They are usuallyintensified during periods of emotional upsets or acute

neuropsychology t 181

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