To investigate the semantic memory of aphasic patients, classification tasks were administered to Broca's, Wernicke's, Mixed aphasics, and normal adults in two experiments. The subjects were shown some drawings of various objects and asked to classify them into two conceptual categories.
If the semantic memory were impaired, the drawings would not be classified into conceptual categories well.
The aphasics classified them into conceptual categories less well than the normals. And the Mixed aphasics did less well than the Broca's and Wernicke's aphasics. The semamtic distance between the two categories in each task had an effect on all the aphasic groups, especially on the Wernicke's aphasics. The visual similarity between them had an effect on the Broca's and Mixed aphasics, especially on the Mixed aphasics.
The findings indicate that many aphasic patients have a disturbance in semantic memory.

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Western Aphasia Battery (Japanese edition, 1986) and a calculation test were administered to 50 aphasic patients. The severity of aphasia and the degree of calculation disorder were found to have a signsificant positive correlation. However, apart from the average population, there were two types of patients who demonstrated severe language disorder but relatively less impaired calculation ability, and vice versa.
The two group's performance on calculation tasks and aphasia subtests were arranged in a correlation matrix. Non-verbal intellectual ability was found to be the most significant factor affecting calculation ability, followed by auditory comprehension and reading comprehension.
The identical calculation problems, which were designed to be simple for normal adults, were administered in three modes: verbal calculation, written calculation, and multiple choice format conveyed in a verbal and written mode. The patients' performance levels varied depending on the language modalities used for the task. This seemed to be due to the involvement of language competence at the phase of decoding the problem and the phase of the formation of the response. These observations suggest that the calculation inability of aphasics is a combination of non-verbal intellectual dysfunction and language disorder.

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Metaphors supply flexibility, expressibility, and a method by which to expand language.
In this study, verbal and nonverbal tests that probed metaphoric capacity were devised using body parts-i. e. eyes, hands, mouth and legs. The subjects were 30 aphasic patients (15 fluent and 15 nonfluent) and 10 normal controls. There tests included basic tests of non-metaphoric operations, metaphor tests and spatial analogy tests. The metaphor tests involved production and comprehension tasks to identify whether the subjects could apply the words of body parts to other objects which have a physical similarity. The spatial analogy tests required the subjects to map body parts onto trees in either upright, horizontal, or upside-down orientation.
The results showed that the aphasics had difficulty in applying the well-known words of body parts to the parts of other objects as metaphor, the use of which is familiar in normal language. When all the heights of relative positions of the mapped body parts on trees were compared, some vertical reversals were present in aphasics. Certain responses of fluent aphasics implied the deficits of semantic components underlying the mechanism of naming. Therefore methods must be developed for lexical training, for aphasic patients, which will help them transfer words metaphorically.

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