Does Chronometry Have a Place in Assessing Math Disorders

Abstract The purpose of this pilot study was to determine if a single math-based chronometric task could accurately discriminate between college students with and without a diagnosed math disorder. Analyzing data from 31 students (6 in the case group, 25 in the clinical comparison group), it was found that the single chronometric task could accurately predict students who did not have a diagnosed math disorder, but not students who had the diagnosis. Moreover, no other non-math psychometric task could add to the predictive power of the chronometric task, indicating that the role of chronometry warrants further study. ********** Scientists have long made use of mental chronometry (Jensen, 1985). Chromometric (i.e., time-based measures) tasks made their way into psychological research in the late 1800s with the work of Franciscus Donders (1868-1869/1969) and Francis Galton (1883). While Donders was interested in using chronometric tasks to uncover details involved in elemental cognitive processes (e.g., discrimination, apprehension), Galton was more concerned about using them to study individual differences. Donders' research agenda has been carried on in the field of experimental psychology (Meyer, Osman, Irwin, & Yantis, 1988), whereas Galton's branch of inquiries largely halted after his death. In the late twentieth century though, a group of researchers began to reinvestigate Galton's ideas and produced a formidable literature on the subject (Deary, 2000; Jensen, 1998; Vernon, 1987). While a significant portion of research in the individual differences renaissance sought to determine how performance on time-based tasks related to overall cognitive functioning, defined as g by Spearman (1904), others sought to see how they differed across various psychopathologies (Posner, 1978). Some have even argued that chronometric tasks have the potential for use in clinical batteries (i.e., assessing the presence of learning disorders; Jensen, 1987; Kulak, 1993; Swanson, 1987). For example, Jensen (1987) and Kranzler (1994) assert that research and theory on learning disabilities (LD) cannot significantly advance until researchers and clinicians use instruments that are more sensitive to the nexus of the brain-behavior relationship than are more traditional psychometric instruments (e.g., the Wechsler scales). Consequently, they have suggested the use of mental chronometric instruments. Because chronometric tasks minimize extraneous influences on task performance (e.g., task strategies), they tend to be much more sensitive to the individual differences involved in various aspects of information processing. If one were to develop subject-specific chronometric tasks (e.g., math facts), it would be assumed that they could better measure individual differences in information processing within that specific domain than more traditional psychometric instruments. To date, minimal research has been conducted in the field of LD with chronometric tasks, especially concerning processing differences between those with and without an LD. Existing findings have been encouraging, however. For example, Whyte, Curry, and Hale (1985) and Kranzler (1994) found significant differences in the performance of various chronometric tasks between individuals with and without a reading disorder, although the specific tasks used (e.g., inspection time) tend to be a proxy for general cognitive ability (Kranzler & Jensen, 1989; Luciano et al., 2004). Cisero, Royer, Marchant, and Jackson (1997), in a series of studies with chronometric tasks designed specifically to assess various components of the reading process, found that college students with reading learning disabilities consistently took longer to process and respond to various lexical stimuli (e.g., word and pseudo-word naming)--a result that not only differentiated them from a non-diagnosed sample, but also from a "generalized learning disability" sample. Likewise, Hayes, Hynd, and Wisenbaker (1986) found significant differences on a battery of chronometric tasks between college students with and without a diagnosed LD, even after controlling for cognitive ability. …