Diagnosis Threat Research Articles

Slowing Down after a Mild Traumatic Brain Injury: A Strategy to Improve Cognitive Task Performance?

Long-term persistent attention and memory difficulties following a mild traumatic brain injury (TBI) often go undetected on standard neuropsychological tests, despite complaints by mild TBI individuals. We conducted a visual Repetition Detection working memory task to digits, in which we manipulated task difficulty by increasing cognitive load, to identify subtle deficits long after a mild TBI. Twenty-six undergraduate students with a self-report of one mild TBI, which occurred at least 6 months prior, and 31 non-head-injured controls took part in the study. Participants were not informed until study completion that the study's purpose was to examine cognitive changes following a mild TBI, to reduce the influence of "diagnosis threat" on performance. Neuropsychological tasks did not differentiate the groups, though mild TBI participants reported higher state anxiety levels. On our working memory task, the mild TBI group took significantly longer to accurately detect repeated targets on our task, suggesting that slowed information processing is a long-term consequence of mild TBI. Accuracy was comparable in the low-load condition and, unexpectedly, mild TBI performance surpassed that of controls in the high-load condition. Temporal analysis of target identification suggested a strategy difference between groups: mild TBI participants made a significantly greater number of accurate responses following the target's offset, and significantly fewer erroneous distracter responses prior to target onset, compared with controls. Results suggest that long after a mild TBI, high-functioning young adults invoke a strategy of delaying their identification of targets in order to maintain, and facilitate, accuracy on cognitively demanding tasks.

Effects of “Diagnosis Threat” on Cognitive and Affective Functioning Long After Mild Head Injury

Persistent cognitive complaints are common following a mild head injury (MHI), but deficits are rarely detected on neuropsychological tests. Our objective was to examine the effect of symptom expectation on self-report and cognitive performance measures in MHI individuals. Prior research suggests that when MHI participants are informed they may experience cognitive difficulties, they perform worse on neuropsychological tests compared to MHI participants who are uninformed. In this study, undergraduate students with and without a prior MHI were either informed that the study's purpose was to investigate the effects of MHI on cognitive functioning ("diagnosis threat" condition) or merely informed that their cognitive functioning was being examined, with no mention of status ("neutral" condition). "Diagnosis threat" MHIs self-reported more attention failures compared to "diagnosis threat" controls and "neutral" MHIs, and more memory failures compared to "diagnosis threat" controls. In the "neutral" condition, MHIs reported higher anxiety levels compared to controls and compared to "diagnosis threat" MHIs. Regardless of condition, MHIs performed worse on only one neuropsychological test of attention span. "Diagnosis threat" may contribute to the prevalence and persistence of cognitive complaints made by MHI individuals found in the literature, but may not have as strong of an effect on neuropsychological measures.

Giving Context to Post-Deployment Post-Concussive-Like Symptoms: Blast-Related Potential Mild Traumatic Brain Injury and Comorbidities

In the military and Veterans Administration systems, individuals with potential MTBI are presenting with symptoms in excess of what would be expected based on initial injury characteristics and/or at unexpected time periods based on current research findings. This article investigates factors that might account for the discrepancy between current research expectations and some occurrences in clinical practice. The physics of blast waves, as well as animal and human research, relevant to explosions are reviewed. Additional factors that occur within the military blast exposure milieu are also explored because the context in which an injury occurs can potentially impact symptom severity and course of recovery. Differential diagnoses, iatrogenic illness, diagnosis threat, and symptom embellishment are also considered.

Further exploration of the effect of “diagnosis threat” on cognitive performance in individuals with mild head injury

The present study further explored the phenomenon of "diagnosis threat" (Suhr & Gunstad, 2002), by examining the potential explanatory roles of anxiety, effort, and depression. Individuals with mild head injury history were randomly assigned to receive either neutral instructions (controls, N = 25) or to have attention called to their head injury history as a reason for invitation into the study (diagnosis threat, N = 28). Depression was measured at baseline. Following the neuropsychological battery, ratings of effort, test pressure, and state anxiety were completed. The diagnosis threat group performed worse than controls on attention/working memory, psychomotor speed, and memory tasks, but not on measures of executive functioning, post-test anxiety, or effort. Effort, anxiety and depression were not related to cognitive performance, nor did depression interact with expectations in explaining group differences in performance. Results provide further support for the "diagnosis threat" effect, but offer no support for effort, anxiety, or depression explanations for diminished performance.

“Diagnosis Threat”: The Effect of Negative Expectations on Cognitive Performance in Head Injury

The present study examined the effect of negative expectations on neuropsychological test performance. It was hypothesized that having attention called to a history of prior head injury and the potential effects of head injury on cognition would result in diminished neuropsychological test performance relative to individuals with a similar head injury history but who did not have their attention called to their head injury history (‘diagnosis threat’). Of 36 participants with a history of mild head injury, 17 were randomly assigned to diagnosis threat and 19 to neutral test directions. The diagnosis threat group performed significantly worse on tests measuring general intellect and memory, but were not different from the neutral group in basic attention or psychomotor speed. The diagnosis threat group rated themselves as putting forth less effort on the neuropsychological battery, and self-rated effort correlated with test performance in that group. Overall, results serve as a reminder that neuropsychological tests are measures of behavior, and thus can be influenced by nonneurological factors.