Memory versus Conceptualization

Each of the seven WAIS-III Verbal subtests makes demands on a person's memory and concept formation, although they differ considerably in the relative role assigned to each function. At one extreme is Digit Span, a test of short-term memory with a small conceptual component, the ability to reverse digits. Similarities occupies the opposite extreme of high conceptual-low memory. The ability to find the common, preferably abstract, element that unites two verbal concepts is perhaps a prototypical conceptual task. Memory is required to remember the examiner's question (short-term) and to retrieve the two concepts from storage (long-term), but the demands are minimal on both counts. The questions are short, and reduce to just two words, the concepts to be compared; further, the concepts themselves are simple, common, and usually overlearned.

Whereas dividing the Verbal scale into memory and conceptual halves is neither pure nor unequivocal, there has been some consensus on this type of dichotomy within the literature. In both Guilford's and Horn's models, the following subtests have a clear-cut memory component: Letter-Number Sequencing, Digit Span, and Arithmetic (Information is considered by Guil-ford to have a semantic memory component and involves long-term retrieval of facts). In contrast, Vocabulary, Comprehension, and Similarities are considered good measures of one or more of the following by Bannatyne, Guilford, Rapaport, or Dean: concept formation, judgment, cogni tion, evaluation, abstract thought, and social comprehension. Indeed, this triad of subtests composes Bannatyne's Verbal Conceptualization category.

Nonetheless, Arithmetic is classified by Guilford as a measure of cognition as well as memory, and Vocabulary is categorized by Rapaport as a dual measure of concept formation and memory. Hence, when examiners search for a memory-conceptualization split within the WAIS-III Verbal Scale, they must do so with flexibility and with the awareness that most Verbal subtests are complex.

Ben's Verbal profile (below) provides a good example of a clear-cut memory-reasoning split (conceptual subtests are in bold face).

Verbal Subtest Scaled Score

Information 9

Digit Span 8

Vocabulary 16

Arithmetic 10

Comprehension 11

Similarities 15

Letter-Number Sequencing 10

Without computing significant strengths and weaknesses, and without following a systematic, sequential method of hypothesis generation, simultaneous processors should immediately detect a strength in conceptualization, contrasted with a generalized weakness in short- and long-term memory. Ben's highest memory score was one point less than his lowest conceptualization score. To ensure that this configuration is significant, compute his mean score in each category (14.0 in conceptualization—averaging Vocabulary, Similarities, and Comprehension, versus 9.3 in memory—averaging Digit Span, Arithmetic, Letter-Number Sequencing, and Information) and subtract these means (4.7 points, or 5 points after rounding the means to whole numbers). This value exceeds the rule of thumb of 3 points needed to denote a meaningful difference.

Of the Verbal subtests, Digit Span and Letter-Number Sequencing are generally the "cleanest" measures of memory, while Comprehension and Similarities are the "purest" tests of verbal conceptualization. Sometimes these two competing dyads will be considerably different from each other, in either direction, suggesting a possible difference in the person's memory and conceptual abilities; in this instance, examiners relying on a configuration approach to hypothesis generation need to be prepared to ignore the complex Arithmetic and Vocabulary subtests and focus on the best measures of each ability. As stated, whenever examiners use the configuration approach to subdivide a person's WAIS-III subtests into strong and weak areas, they should routinely confirm the significance of the finding by the simple procedure of verifying that the mean scaled scores differ by at least 3 points.

Further, the fact that the groupings discussed in this section have been labeled "memory" and "conceptualization" is no guarantee that an obvious split of a Verbal profile into these groups reflects differences in these skill areas. The interpretation of the person's strength and weakness must be verified with behavioral and background data, inasmuch as other explanations are possible, even conceivable. This point becomes apparent in the next section, which deals with a competing interpretation of the same Verbal scale dichotomy.

Understanding And Treating Autism

Understanding And Treating Autism

Whenever a doctor informs the parents that their child is suffering with Autism, the first & foremost question that is thrown over him is - How did it happen? How did my child get this disease? Well, there is no definite answer to what are the exact causes of Autism.

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