Self-Reported Memory Problems: New Data on the Influence of Psychiatric Status and Normative Dissociative Experiences
Sam Goldstein, Ph.D.
In a number of my Legal Updates over the past ten years, I have summarized research on the effects of multiple phenomena such as pain, related life stress and specific psychiatric problems upon neuropsychological test performance and daily functional impairment. Among these phenomena the role depression may play in an individual’s perception of their cognitive abilities in every day functioning has likely been the most debated. Such findings have varied significantly with issues raised concerning researcher’s ability to control for confounding differences between control and experimental groups. Issues such as age, education, comorbid psychiatric problems, life history, medications and traumatic brain injury have all been questioned as possibly responsible for many of the differences found between studies. In fact a number of researchers have reported that there is a lack of a coherent theory to explain any true impact psychiatric disorders such as depression might have on memory function. Many of these studies did not include groups of individuals with neurological problems such as traumatic brain injury or for that matter individuals involved in litigation as the result of injury. Yet, this issue has and continues to be a critical phenomena when neuropsychologists are asked to determine whether an individual’s daily complaints about memory or cognitive inefficiency are the result of psychiatric conditions, trauma, premorbid status or a combination. It is still not uncommon in the forensic neuropsychological literature for differences in test performance to be randomly attributed to psychiatric and/or organic causes.
In 2002, Martin Rohling and colleagues, examined a population of 420 individuals with a two day comprehensive neuropsychological evaluation completed as part of compensation disability claims. Half of the individuals were referred as the result of actual or alleged head injuries. Twenty percent for depression, 10% for other neurological problems, 5% with Chronic Fatigue Syndrome, 4% with orthopedic injuries, 4% with chronic pain and 6% with miscellaneous other diagnoses. As I reported in NLBC Legal Update Issue #16 in 2002, the results were extremely interesting and inconsistent with a number of previous research studies. Insignificant correlations between measures of depression and various clusters of neurocognitive testing were found. No significant relationships were found between objective performance and severity of depression either. Patients with high symptoms of depression reported significantly more daily problems with memory than did patients who were in a low depression symptom group. However, when memory complaints were compared to actual performance, no relationship was revealed. Self-perceptions and memory function bore little relation to objective performance.
A recent study further adds to this important and emerging literature. James Bruce at the University of Missouri-Kansas City and colleagues, recently published the results of an examination of self-reported memory problems in patients with Multiple Sclerosis. In this population there is research literature demonstrating that self-reported cognitive difficulties do not typically correlate well with objective neuropsychological evaluation. The authors examined the relationship between self-reported memory, dissociation (defined as the disruption of an individual’s usually integrated cognitive processes such as consciousness, memory, identity or perception) and test scores. Self-reported memory problems were found to be associated with more reports of depression and anxiety. Self reported memory was not significantly associated with performance on any of the neuropsychological variables. The authors pose a causal model for normative dissociation mediating the relationship between emotional problems and perceived cognitive problems. They suggest that increased depression, anxiety and related psychiatric conditions were all significantly correlated with more dissociative, cognitive failures which in turn were strongly associated with perceived memory problems. The authors note that dissociative experiences are present to a greater or lessor degree in everyone and can take many forms. They suggest, based on a review of the research literature, that 80% to 90% of normal individuals report dissociative symptoms at least some of the time. While the majority of adults report mild dissociative experiences such as losing awareness while driving then suddenly discovering some distance has been traveled, few adults report more extreme dissociative experiences such as multiple identities. Researchers have demonstrated that in normal populations a pattern of dissociative symptoms are associated with both psychiatric disturbance and perceived cognitive difficulty. In contrast, dissociation is not typically associated with objective measures of cognitive performance.
If these results can be replicated in populations of primary psychiatric patients as well as those with neurological problems the data may ultimately be used to assist neuropsychologists in making a better determination as to the cause of self-reported cognitive inefficiency and memory problems, particularly in populations of individuals with traumatic brain injury. It may certainly be the case that disruption of every day life secondary to even a mild traumatic brain injury, may lead to increased dissociative states that in the end disrupt functional ability regardless of neurological status. Nonetheless, results of this study provide further evidence that the relationship between self-reported memory problems and neurocognitive testing in many populations is often non-existent or weak. These findings hold significant theoretical and clinical implications. In clinical and forensic settings a better understanding of these processes may inform practice and validate patients’ perceptions of cognitive decline while simultaneously offering reassurance that dissociative events can be normal and transient for their conditions.
Related References
Bruce, J.M., & Arnett, P. (2005). M.S. patients with depressive symptoms exhibit affective memory biases when verbal and coding strategies are suppressed. Journal of the International and Neuropsychological Society, 11, 514-521.
Bruce, J.M., Bruce, A.S., Hancock, L., & Lynch, S. (2010). Self-reported memory problems in Multiple Sclerosis: Influence of psychiatric status and normative dissociative experiences. Archives of Clinical Neuropsychology, 25, 39-48.
Christodoulou, C., Melville, P., Cherl, W.F., Morgan, T., MacAllister, W.S., Canforid, M., et al. (2005). Perceived cognitive dysfunction in observed neuropsychological performance: Longitudinal relation in persons with Multiple Sclerosis. Journal of International Neuropsychological Society, 11, 614-619.
Gershuny, B.S., & Thayer, J.F. (1999). Relations among psychological trauma, dissociative phenomena and trauma related distress: A review and integration. Clinical Psychology Review, 19, 631-637.
Ray, W.J., & Faith, M. (1995). Dissociative experiences in a college age population: Follow-up with 1,190 subjects. Personality and individual differences, 18, 223-230.
Rohling, M.L., Green, P., Allen, L.M., & Iverson, G.L. (2002). Depressive symptoms and neuropsychological test scores in patients passing symptom validity tests. Archives of Clinical Neuropsychology,17, 205-222.
