Malingering or expected deficits? A case of herpes simplex encephalitis

CVLT-II Forced Choice Recognition Trial as an Embedded Validity Indicator: A Systematic Review of the Evidence

OBJECTIVES

The Forced Choice Recognition (FCR) trial of the California Verbal Learning Test, 2nd edition, was designed as an embedded performance validity test (PVT). To our knowledge, this is the first systematic review of classification accuracy against reference PVTs.

METHODS

Results from peer-reviewed studies with FCR data published since 2002 encompassing a variety of clinical, research, and forensic samples were summarized, including 37 studies with FCR failure rates (N=7575) and 17 with concordance rates with established PVTs (N=4432).

RESULTS

All healthy controls scored >14 on FCR. On average, 16.9% of the entire sample scored ≤14, while 25.9% failed reference PVTs. Presence or absence of external incentives to appear impaired (as identified by researchers) resulted in different failure rates (13.6% vs. 3.5%), as did failing or passing reference PVTs (49.0% vs. 6.4%). FCR ≤14 produced an overall classification accuracy of 72%, demonstrating higher specificity (.93) than sensitivity (.50) to invalid performance. Failure rates increased with the severity of cognitive impairment.

CONCLUSIONS

In the absence of serious neurocognitive disorder, FCR ≤14 is highly specific, but only moderately sensitive to invalid responding. Passing FCR does not rule out a non-credible presentation, but failing FCR rules it in with high accuracy. The heterogeneity in sample characteristics and reference PVTs, as well as the quality of the criterion measure across studies, is a major limitation of this review and the basic methodology of PVT research in general. (JINS, 2016, 22, 851-858).

Cognitive dysfunction during anti-NMDA-receptor encephalitis is present in early phase of the disease

Anti-NMDA-receptor encephalitis is an autoimmune disorder with a well-defined set of clinical features including psychiatric changes (anxiety, agitation, bizarre behaviour, delusional or paranoid thoughts), epileptic seizures and cognitive disturbance followed by movement disorders including orofacial dyskinesias, alterations in the level of consciousness and dysautonomia. Although the cognitive changes are not always very clear at presentation, they can persist after recovery from the acute and often prolonged illness. However, there are few studies describing neuropsychiatric changes in depth, both in the early course of the disease and in long-term follow-up.

Amnesic disorders

Memory disturbances frequently occur after brain damage, but can be associated with psychiatric illnesses as well. Amnesia--the most severe form of memory impairment--has several variants, including anterograde and retrograde amnesia, material-specific and modality-specific amnesia, and transient global amnesia. We searched databases to obtain an overview of amnesia research from the past 5 years. Research into amnesia has increased exponentially, probably because of the availability of modern brain-imaging techniques. In line with the view that memory is not a unity but is organised into several systems, amnesia is described as a multifaceted disease with a frequently poor prognosis.