Commentary on “Cogniform disorder and cogniform condition: Proposed diagnoses for excessive cognitive symptoms” by Dean C. Delis and Spencer R. Wetter

Abstract

In 1999, Slick, Sherman, and Iverson presented the first diagnostic algorithm designed to be used to identifylevels of “malingered neurocognitive dysfunction (MND).” The term “definite MND” was used to designate thoseindividuals who had motive to feign and obtained significantly below chance performance on one or more forcedchoice paradigms, while “probable MND” was used to refer to individuals who did not fall significantly below chanceon forced choice measures but did have incentive to feign and failed two or more non-forced choice effort measures,or failed one non-forced choice measure and displayed at least one example of non-plausible self-reported symptomsor test data discrepancy. “Possible MND” was used to identify those individuals with incentive to underperform andwho evidenced discrepant information on self-report. However, since the publication of that pivotal and widely citedmanuscript, questions have arisen as to whether we are in fact detecting “malingering” when poor performance oneffort indicators is observed.Malingering refers to the conscious, deliberate feigning of symptoms for external gain, but it has long been appreci-ated that non-conscious symptom fabrication, including feigned cognitive dysfunction, can also occur. For example, inFreud’soriginalreportsofindividualswithconversiondisorder(whichinvolvesnon-consciouscreationofneurological-type symptoms), cognitive complaints were prominent; “Freud’s remarks about Frau Cecile von M indicate that herhysterical attacks and neuralgias were accompanied by reversible amnesia and clouding of consciousness” (Mace,1994, p. 186). In the ensuing decades, interest in conversion disorders increasingly focused on the dramatic non-plausible physical symptoms, and the accompanying cognitive pseudosymptoms, while still prevalent, unfortunatelylost visibility.If we are to use the Slick, Sherman, and Iverson (1999) criteria to diagnose “malingered” cognitive symptoms, wemust have objective means by which to differentiate between consciously versus non-consciously produced symp-tom fabrication. However, no such techniques exist. For example, while forced choice measures are now frequentlytouted as the “gold standard” for identifying malingered cognitive performance (see Bianchini, Mathias, & Greve,2001), in fact this paradigm was originally used to document conversion disorder (Pankratz, 1979). Of relevance, inhypnotized individuals, whose behavior is presumed not to be under conscious control, significantly below chanceperformance on forced choice measures occurs in 25% of those instructed to produce amnesia (Spanos, James, & deGroot, 1990). Unfortunately, personality inventories are similarly unhelpful in distinguishing between consciously and