Applying Luria's Diagnostic Principles in the Neuropsychological Assessment of Children

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  • Neuropsychology Review, Vol. 9, No. 2, 1999

    Applying Luria's Diagnostic Principles in theNeuropsychological Assessment of Children

    Marit Korkman1,2

    The first part of this article examines the theoretical justification for applying Luria's approach in theassessment of children. It is concluded that Luria's concepts of functional systems and the principleof specifying primary and secondary deficits may be applied to children. However, the selection offunctional components to assess should be based on traditions of child neuropsychology rather thanon Luria's assessment of adults. In addition, the tendency for comorbid disorders, mechanisms ofneural adaptation to damage, and the prevalent types of brain abnormality in children render brain-behavior relationships more complex in children than in adults. The second part of the article describeshow Luria's methods were adapted for use with children. An assessment, NEPSY, was developedby integrating Luria's views with contemporary child neuropsychological traditions. The NEPSYincludes 27 homogeneous and psychometrically developed subtests, standardized in the United Statesand Finland for the age range of 3 to 12 years. The rationale of analyzing disorders of cognitiveprocesses through a comprehensive and systematic assessment of their components, characteristic ofLuria's approach, was preserved, but more specific principles of diagnosis were modified. Researchfindings obtained with a previously published, Finnish NEPSY version are presented.

    INTRODUCTION

    Luria's theory and methods were mainly based on hisexperience of adult patients sustaining focal brain dam-age (Luria, 1973). Compared with children with devel-opmental or congenital neuropsychological dysfunction,who constitute the majority of the children referred forneuropsychological assessments, Luria's patients repre-sented the opposite pole on the dimensions of early ver-sus late and chronic versus acute brain damage. The firstpart of this article examines to what extent there is theo-retical justification for an application of Luria's conceptsand methods to children. The second part describes howLuria's methods have been adapted for the assessment ofchildren with developmental, congenital, or acquired braindysfunction.

    1Helsinki University Central Hospital, Hospital for Children and Ado-lescents, Pediatric Neurology, Helsinki, Finland, and Abo AcademyUniversity, Turku, Finland.

    2 All correspondence should be directed to the author at Avenue AlbertJonnart 89, B-1200 Brussels, Belgium.

    APPLICABILITY OF LURIA'S APPROACHTO CHILD NEUROPSYCHOLOGY

    Luria's Concepts and Methods

    Functional Systems

    The basic concept of Luria's theory is his view ofhigher mental activity, or, in more recent terminology,cognitive processes (author's remark), as dynamic func-tional systems. According to this view, cognitive processesshould be seen as functional systems characterized by aspecific aim but carried out by a system of interconnectedsubprocesses, or components, in a dynamic and variablefashion (Luria, 1973, pp. 26-30).

    Verbal processes, for example, include at least the fol-lowing components: inner speech, comparable to a draftof a verbal formulation; oral articulatory motor series;kinesthetic feedback from articulatory movements; audi-tory phonemic analysis of speech; short-term memory al-lowing processing of the message; perception of spatial

    891040-7308/99/0600-0089$16.0/0 C 1999 Plenum Publishing Corporation

    KEY WORDS: Luria; neuropsychology; neurocognitive; assessment; children.

  • 90 Korkman

    Table I. Components of Cognitive Processes According to Luna"

    AttentionRegulation of vigilance, activity levelSelective attention to biologically relevant stimuliVerbal regulation, goal-directed attentionInhibition of irrelevant stimuli and impulses

    LanguageInner speechMotor programming of successive articulemesArticulation based on kinesthetic feedbackAcoustic phonemic analysis of speechAcoustic memoryLexical-semantic retrieval, namingLogical-grammatical aspects: syntax and concepts

    Movement and ActionIntention and planDynamic organization of motor seriesAfferent (i.e., kinesthetic, tactile, visual) feedbackOrientation of movements in space

    Perceptual FunctionsVisual fieldPerception of surrounding space and own bodyVisual analysis and synthesisPerception of spatial coordinatesConstructional ability

    Memory and LearningAuditory-verbal (short-termb) memoryVisual and spatial (short-termb) memoryCoding and long-term storagePreservation versus inhibition of memory tracesActive memorizing

    Example of Complex PerformanceProblem SolvingAnalysis of conditionsStrategy formationExecution of planEvaluation

    aAfter Luria (1973).b Author's addition.

    dimensions of language, inherent in logical concepts andsyntax; and semantic retrieval.

    The composition of language, memory, attention, mo-tor performance, and thinking is described in detail byLuria (1970,1973). A summary of components of impor-tant functions is presented in Table I.

    Developmental Aspects

    Luria draws attention to some developmental changesto illustrate the dynamic structure of cognitive functions.For example, a young child copying a text needs to activelyidentify and produce the graphic characteristics of eachletter, whereas an adult automatically transfers the per-ceived written text into overlearned motor schemes. Thestructure of acquired skills may thus become more crys-tallized as a function of experience (Luria, 1973, p. 32).

    Of special interest to child neuropsychology is Luria'sview, based on Vygotsky's (1965), of the development ofattention. The young child's attention is automatically at-tracted to novel or exciting stimuli, and the child tendsto react impulsively, in accordance with concrete stim-uli rather than verbalized rules and commands. It is, forexample, very difficult for a 2-year-old child to obey acommand to take off the shoes that he or she has just be-gun to put on.

    The capacity for conscious attention and behavioralcontrol is formed in the child's interaction with the adult.The adult directs the child's attention by gestures, words,and instructions. The child gradually internalizes and takesover this control. By this mechanism, culturally medi-ated motives and behavior programs are transmitted to the

    child. Verbal regulation becomes a particularly forcefulmedium for control of attention, behavior, and complexperformance (Luria, 1961a; 1961b; 1973, pp. 261-264).Luria's concept of verbal regulation is thus comparable tothe concept of executive functions.

    Localization of Functions

    The components of the functional systems reflect theactivity of specific brain regions. The brain is viewed as"a functional mosaic" the parts of which in various com-binations provide the neural basis of cognitive processes(Luria, 1963, pp. ix-x; 1973, pp. 11, 26-30). The func-tional organization of the brain is described in detail byLuria (Luria, 1970, 1973).

    Clinical Assessment

    The components of complex processes are repre-sented in the clinical assessment by specific tasks. Manytasks are designed so that they depend as much as possibleon a specific aspect of functioning; others are more com-plex. Disordered functions are analyzed one componentat a time, to determine which is the primary deficit in thechain of subprocesses.

    The process of determining primary and secondarydeficits is, however, not entirely straightforward, becauseeven very focused tasks are complex and may depend onvarious contributing subprocesses. The interpretation isbased on logical deduction of what underlying deficit issufficient and necessary to explain the findings, a principlecalled syndrome analysis.

  • Applying Luria's Principles in the Assessment of Children 91

    The way in which tasks are failed may also provideimportant clues as to the nature of the deficit. For example,difficulties in speech production, with relative preserva-tion of verbal comprehension, would point to some type ofmotor aphasia. Difficulties in production of phonologicalsequences and perseverative errors would point to a mo-tor programming deficit (efferent motor aphasia), whereasdifficulties articulating particular phonemes may indicatea problem with sensory feedback of articulation (afferentmotor aphasia).

    Specifying primary deficits clarifies the nature of thepatient's cognitive disabilities and provides a basis forplanning rehabilitation as well as for the patient's abilityto cope with his or her problems.

    Another aim of the neuropsychological assessmenthas been to aid in determining the localization of the dam-age. When the primary deficit underlying a patient's find-ings can be specified, the localization of the underlyingbrain dysfunction may also be determined. Modern brainimaging techniques have, however, replaced neuropsycho-logical assessments in the localization of brain damage.When the localization of damage is known, this may, in-stead, provide a source of verification of the interpreta-tion of neuropsychological findings. Findings indicatingdamage to Wernicke's area would, for example, support ahypothesis of a receptive aphasia with impaired phonemicanalysis as the primary deficit.

    The syndrome analysis is facilitated by Luria's taxon-omy of aphasias, apraxias, agnosias, amnesias, and otherdisorders. The descriptions of syndromes include clinicalcharacteristics, primary and secondary deficits, and prob-able localization of damage (Christensen, 1984; Luria,1973).

    The assessment is performed with the aid of tasksof a pass/fail type. An orienting, brief assessment is firstperformed across all domains of functioning: language,memory, sensorimotor functions, visuoperceptual func-tions, orientation and attention, and more complex skills.Thereafter, an in-depth analysis of selective domains isperformed in accordance with the findings on the orient-ing assessment, going from simple to more complex tasks.Tasks are selected in accordance with the hypotheses of theexaminer (Christensen, 1975,1984). The hypothesis-test-ing paradigm may be compared with the selection of testsand examinations in medical diagnosis. The examiner for-mulates, tests, and revises hypotheses concerning the typeof disorder, as a continuous process.

    Contemporary Views in Child Neuropsychology

    Many of the concepts included in Luria's theory areshared by most other neuropsychological views, includ-

    ing those of child neuropsychology. Other concepts arespecific to Luria's theory or expressed in terms that makethem difficult to integrate with contemporary views (seeTable I). As was pointed out previously, children may dif-fer from adults with respect to the structure of functionsas well as the types and mechanisms of cognitive disor-ders. In attempting to apply Luria's theory and methods tochildren, the starting point has been Luria's general viewsof functional systems and his clinical approach. However,the specifications of the components to assess in chil-dren, as well as the detailed elaboration of clinical meth-ods, were based primarily on traditions of child neuropsy-chology.

    Functional Systems

    In agreement with Luria's views, contemporary childneuropsychology frequently views cognitive processessuch as attention (Barkley, 1988; Mirsky, 1989) and arith-metic calculations (Sokol et al., 1994) as complex pro-cesses consisting of several subcomponents. These pro-cesses may be disturbed in different ways, depending onwhich components are deficient, which leads to differentsubtypes of disordersfor example, language disorders(e.g., Rapin et al., 1992). Different authors may, however,emphasize different aspects. For example, some authorssee phonological analysis as crucial for reading acquisi-tion (Bradley and Bryant, 1985; Wagner and Torgesen,1987); others emphasize the role of semantic retrieval(naming) (Korhonen, 1991; Wolf and Obregon, 1992)andverbal memory processes (Benezra and Douglas, 1988;Siegel and Ryan, 1989). The following processes, manyof which approximate Luria's concepts, have been delin-eated as important aspects of complex functions.

    Attention. In analyses of attentional processes in chil-dren, many authors account for the following components:selective attention, sustained attention, attention span ordivided attention, and inhibition and control of behavior(Barkley, 1988; Cooley and Morris, 1990; Douglas, 1984;Mirsky, 1989).

    In empirical studies, children with attention deficithyperactivity disorder (ADHD) have been found to be im-pulsive (Barkley, 1988; Korkman and Peltomaa, 1993), tobe hyperactive (Matier-Sharma et al., 1995), and to havefluctuating attention on vigilance tasks, demanding sus-tained, selective attention (Kinsbourne, 1990; Penningtonet al., 1993).

    Executive Functions. Closely related to attention areexecutive functions, that is, planning and strategy employ-ment, ability to maintain and shift set, organized search,and impulse control (Levin et al., 1991; Welsh et al.,1991).

  • 92 Korkman

    Pennington et al. (1993) found children with ADHDto perform poorer than children with learning disorderson tasks of executive functions: the Wisconsin Card Sort-ing Test (see Pennington et al., 1993) and the Towerof London test (see Levin et al., 1991; Shallice, 1982).ADHD children have also performed poorly on tasks de-manding maintenance and shift of set (Kemp and Kirk,1993).

    Language. One component that has been found nec-essary for normal speech and articulation is oral motorprogramming and control of phonological sequences (Halland Tomblin, 1978; Rapin et al., 1992).

    In addition to articulation problems, language-levelexpressive problems may be observed, for example, ontasks of narration of a story (Davenport et al., 1986; Norrisand Bruning, 1988). This type of task is, however, verycomplex because it involves executive functions and mem-ory, in addition to linguistic abilities.

    An important component of language is the auditoryperception and analysis of the phonemic composition ofwords and speech. A deficit in this component may causereceptive language disorders (Rapin et al., 1977; Tallalet al., 1993). More subtle deficits of phonological analysismay lead to dyslexia rather than overt language disorder(Bradley and Bryant, 1985; Scarborough, 1990; Wagnerand Torgesen, 1987).

    Comprehension deficits may also occur withoutany evident underlying phonemic decoding problem(Korkman and Hakkinen-Rihu, 1994).

    Another deficit that frequently occurs in childrenwith language disorders and/or dyslexia is a deficit of se-mantic retrieval, that is, naming. Although most clearlyrelated to dyslexia (Korhonen, 1991; Scarborough, 1990;Wolf and Obreg6n, 1992), dysnomic problems may, bydefinition, be regarded as a language disorder. In addi-tion, they may occur in the context of more generalizedlanguage disorders (Korkman and Hakkinen-Rihu, 1994;Vellutino and Scanlon, 1989).

    Sensorimotor Functions. Luria (1973) distinguishedbetween dynamic and kinesthetic motor organization(see Table I). A similar distinction was made in children byDewey and Kaplan (1994). These authors arrived at...

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