Review of Smith, S., Gorske, T., Wiggins, C. & Little, J. “Personality Assessment Use by Clinical Neuropsychologists.” International Journal of Testing, 10(1), 6 – 20.
Neuroscientists now are on the verge of developing persuasive etiologies for complex psychopathology such as schizophrenia and personality disorder spectra. They have identified precise genetic and neurochemical contributors with highly granulated detail. Genetic markers, for example, occur at the allele level; neurochemical ones are based on specific transmitters within the GABAminergic or dopaminergic systems. Using these techniques such conditions can be empirically modeled – validating one of psychology’s long-cherished objectives, which only can speculate about them at the level of “mind” or “behavior.” This leads however to a serious confound, which is that personality assessment tests such as the MMPI, TAT and Rorschach only measure traits at a gross level, frequently in as few as a half-dozen categories. This is a poor match for the literally millions of genetic and neurochemical data points. What correlates with what?
This article evaluates frequency of use of personality assessment tests by clinical neuropsychologists. The authors sent a questionnaire to 1,000 practitioners and received 404 responses. The authors conclude their use is relatively uncommon. When they were used, MMPI was used more frequently than TAT or Rorschach (both of which had low reliability and validity). All three were used primarily to assess younger patients, where learning disabilities, forensic issues and psychiatric issues may be more prominent. While the authors believe personality assessment measures can be used to assess psychopathology in patients with neurological impairments, they reluctantly conclude there is little relationship between neurophysiological measures and (alleged) personality correlates. They characterize this as presenting a “clinical challenge” when in fact what they should have said is that it is philosophically dubious, for the reasons I set forth.