[Influence of mnemonic, semantic, and conceptual factors on the performance of aphasic patients in the Token Test (author's transl)]. / Zum Einfluss mnestischer, semantischer und konzeptueller Faktoren auf die Leistungen aphasischer Patienten im Token Test.

Three experimental modifications of the Token Test were presented to 40 aphasics with predominantly expressive disturbances and 40 control patients with diffuse brain damage. On each token a human figure was drawn (a man, woman, boy, or girl); the size, color, and form of the token were given in the instructions, or the depicted figure was given as the target either in addition to or instead of the size and form. The mere fact that a figure was depicted on the tokens did not affect the performance of the patients. However, when the figures were mentioned in the instructions, the aphasics' performance improved significantly, although it never reached the level of the controls. An analysis of the error types suggested that the poor performance of the aphasics in the Token Test is at least in part due to difficulties identifying complex stimuli when the features are separately named in the instructions.

Cognitive impairment of aphasics in a colour-to-picture matching task.

Broca's and Wernicke's aphasics, non-aphasic brain-damaged patients and chronic schizophrenics were tested in a colour-to-picture matching task. For each of 42 black-and-white drawings of objects the most "typical" colour was to be selected from a set of 24 colour strips. Separate scores for the appropriateness of the choices as to hue, brightness, and saturation were obtained by comparison with the data from 50 normal Ss. The choices of both aphasic groups were more deviant than those of brain-damaged controls for chromatically coloured objects with respect to all three colour dimensions, and for achromatically coloured objects with respect to saturation and brightness. Wherever the aphasics' performance was worse than that of the controls, the deviancy-scores correlated significantly with the Token Test. Results are interpreted as an impairment of aphasics in the ability to isolate analytically specific features of objects or concepts which might be conceived of as a prerequisite of propositional language.

"Semantic" and "acoustic" errors of aphasic and schizophrenic patients in a sound-picture matching task.

Broca's aphasics, Wernicke's aphasics, brain-damaged patients without aphasia, and chronic schizophrenics were tested on a task to match meaningful sounds to one of four pictures. One of the depicted objects was the natural source of the sound, one was an object belonging to the same semantic category as the correct object, one was an object producing acoustically similar sounds as the correct object, and one was an object not related either semantically or acoustically to the correct object. In one item set the "semantic" distractors produced a sound completely different from the presented one; in another item set the "semantic" distractors made practically no specific sounds at all. Broca's and Wernicke's aphasics were shown to have significantly higher total error scores than brain-damaged patients without aphasia and to make significantly more "semantic" errors only on the first item set and "acoustic" errors on both item sets than the brain-damaged patients without aphasia. However, after correcting for guessing the differences between groups with respect to "semantic" and "acoustic" errors vanished. The aphasics' difficulties in coping with the sound-picture matching task might be difficulties in processing the acoustic dimensions of the items. It is, however, suggested that the impairment is not perceptual but of the cognitive kind repeatedly demonstrated in tasks which require the analytic extraction of features of the stimulus or of the concept represented by the stimulus.

Validity of the Sklar Aphasia Scale.

A German version of the Sklar Aphasia Scale (SAS) was administered to groups of fluent aphasics, nonfluent aphasics, and three control groups (brain-damaged patients without aphasia, schizophrenics, and normal subjects). The SAS discriminated fluent and nonfluent aphasics from schizophrenic brain-damaged, and normal control subjects with a high level of confidence; 91.8% of the aphasic and 81.5% of the brain-damaged patients without aphasia were correctly classified. However, the SAS did not discriminate between fluent and nonfluent aphasics. A factor analysis, which also included the subtests of the Token Test and eight other variables, showed the SAS and the Token Test to load mainly on the same general factor, which represents the severity of language disorders or the impairment of those left-hemisphere functions that might be basic to language. Subtests II and IV of the SAS also had loadings on a memory factor, but none of the subtests had variance on the third factor which represented the sensory-motor or fluency/nonfluencey dimension.

Restricted associations of aphasics and schizophrenics.

Matched groups (N = 25) of fluent and nonfluent aphasics, brain-damaged and normal controls as well as schizophrenics were requested to name (1) as many animals and (2) as many things that are typically yellow as possible within 5 min. The main results of Gloning & Müller (1972) as to smaller numbers of correct responses, higher percentages of repetitions, shorter association clusters, and higher popularity in aphasics could be replicated for animal task. Comparing the data from both tasks for fluent and nonfluent aphasics with the various control groups led to considerable doubts as to what extent these results follow directly from quantitative differences in verbal output or have to be interpreted as qualitative differences in memory storage, retrieval, and self-editing processes.

Aphasic disorders in matching tasks involving conceptual analysis and covert naming.

Aphasic, non-aphasic brain-damaged, schizophrenic and normal Ss were required to select which of two pictures in each item was indicated by a third picture. The latter was related to the referent not through direct associations but only through a mediator: a homonym -- the name for clue and referent --, a situational association, or a perceptual feature common to both. The availability of these mediators was to be tested. Aphasics were as good as normals when the task could be solved via situational associations (e.g. guitar/violin -- bullfight; mediator: "Spain"). They showed poorer performance than all the control-groups not only when the solution depended on the availability of a word but also when it was necessary to identify analytically a perceptual feature characteristic for clue and referent (e.g. swan/turkey -- snowman; mediator: "white"). This result is seen as possibly corresponding to the specific deficiency of both non-fluent and fluent aphasics in the Token Test which might be characteristic of left hemisphere dysfunctions in the analytical decomposition into separate features of what presents itself perceptually and experientally as a unit or Gestalt.