S. Marc Testa

Neuropsychological Functioning in Bipolar Disorder and Schizophrenia

BACKGROUND Some patients with bipolar disorder (BD) demonstrate neuropsychological deficits even when stable. However, it remains unclear whether these differ qualitatively from those seen in schizophrenia (SZ). METHODS We compared the nature and severity of cognitive deficits shown by 106 patients with SZ and 66 patients with BD to 316 healthy adults (NC). All participants completed a cognitive battery with 19 individual measures. After adjusting their test performance for age, sex, race, education, and estimated premorbid IQ, we derived regression-based T-scores for each measure and the six cognitive domains. RESULTS Both patient groups performed significantly worse than NCs on most (BD) or all (SZ) cognitive tests and domains. The resulting effect sizes ranged from .37 to 1.32 (mean=.97) across tests for SZ patients and from .23 to .87 (mean=.59) for BD patients. The Pearson correlation of these effect sizes was .71 (p<.001). CONCLUSIONS Patients with bipolar disorder suffer from cognitive deficits that are milder but qualitatively similar to those of patients with schizophrenia. These findings support the notion that schizophrenia and bipolar disorder show greater phenotypic similarity in terms of the nature than severity of their neuropsychological deficits.

Frequency and bases of abnormal performance by healthy adults on neuropsychological testing

The frequency and determinants of abnormal test performance by normal individuals are critically important to clinical inference. Here we compare two approaches to predicting rates of abnormal test performance among healthy individuals with the rates actually shown by 327 neurologically normal adults aged 18-92 years. We counted how many participants produced abnormal scores, defined by three different cutoffs with test batteries of varied length, and the number of abnormal scores they produced. Observed rates generally were closer to predictions based on a series of Monte Carlo simulations than on the binomial model. They increased with the number of tests administered, decreased as more stringent cutoffs were used to identify abnormality, varied with the degree of correlation among test scores, and depended on individual differences in age, education, race, sex, and estimated premorbid IQ. Adjusting scores for demographic variables and premorbid IQ did not reduce rates of abnormal performance. However, it eliminated the contribution of these variables to rates of abnormal test performance. These findings raise fundamental questions about the nature and interpretation of abnormal test performance by normal, healthy adults.

The utility of regression-based norms in interpreting the minimal assessment of cognitive function in multiple sclerosis (MACFIMS)

The Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) is a consensus neuropsychological battery with established reliability and validity. One of the difficulties in implementing the MACFIMS in clinical settings is the reliance on manualized norms from disparate sources. In this study, we derived regression-based norms for the MACFIMS, using a unique data set to control for standard demographic variables (i.e., age, age2, sex, education). Multiple sclerosis (MS) patients (n = 395) and healthy volunteers (n = 100) did not differ in age, level of education, sex, or race. Multiple regression analyses were conducted on the performance of the healthy adults, and the resulting models were used to predict MS performance on the MACFIMS battery. This regression-based approach identified higher rates of impairment than manualized norms for many of the MACFIMS measures. These findings suggest that there are advantages to developing new norms from a single sample using the regression-based approach. We conclude that the regression-based norms presented here provide a valid alternative to identifying cognitive impairment as measured by the MACFIMS.

Mood, Personality, and Health‐related Quality of Life in Epileptic and Psychogenic Seizure Disorders

Summary:  Purpose: Patients with psychogenic nonepileptic seizures (PNES) rate their health‐related quality of life (HRQOL) more poorly than those with epileptic seizures (ES). This has been explained in part by mood state. We sought to investigate whether HRQOL differences between diagnostic groups (PNES vs. ES) can be explained by additional, perhaps chronic, aspects of mood and personality. An understanding of these relationships may inform treatment designed to improve HRQOL in ES or PNES.

Accuracy of Self-Reported Neuropsychological Functioning in Individuals with Epileptic or Psychogenic Nonepileptic Seizures

The aim of this study was to determine the degree to which subjective ratings of neurocognitive ability accurately reflect objectively measured neuropsychological functioning in patients diagnosed with epileptic (ES, n = 45) or psychogenic nonepileptic (PNES; n = 37) seizures. Patients received a battery of neuropsychological tests, measures of current mood state, and the Quality of Life In Epilepsy-89 questionnaire. Results indicated that subjective ratings of neuropsychological functioning were only partially accurate within each group. Patients with ES accurately rated their memory function, but overestimated language and attention abilities. Patients with PNES accurately rated attention, but underestimated memory and overestimated language. In both groups, poorer self-reported neurocognitive functioning was strongly related to poorer mood state; however, mood state did not predict objectively measured neurocognitive abilities. Given the inaccuracies that exist in patient self-report, results highlight the importance of a comprehensive neuropsychological assessment when evaluating the neurocognitive status of individuals with seizures.

Development, Psychometric Properties, and Validity of the Hopkins Adult Reading Test (HART)

We describe the development of a 35-item, oral word-reading test with two equivalent forms (HART-A and HART-B) designed to estimate premorbid abilities. Both forms show excellent internal consistency (coefficients alpha >.91) and test–retest reliability (Pearson rs >.90). HART performance was combined with demographic variables to generate regression equations that predict IQ scores obtained concurrently and 4–8 years earlier. The resulting models explained 61% of full scale IQ (FSIQ) variability in 327 healthy adults. The FSIQs that can be estimated range from below 73 to above 131. Combined with demographic variables, these two brief word reading tests accurately predict a broader range of IQs than Blair and Spreens (1989) longer version. Equivalent forms make it especially useful for longitudinal studies.

Preoperative assessment of confrontation naming ability and interictal paraphasia production in unilateral temporal lobe epilepsy

The present study examined the diagnostic utility of confrontation naming tasks and phonemic paraphasia production in lateralizing the epileptogenic region in patients with temporal lobe epilepsy (TLE). Further, the role of intelligence in moderating the diagnostic utility of confrontation naming tasks was assessed. Eighty patients with medically intractable complex partial seizures (40 left TLE, 40 right TLE) received the Boston Naming Test (BNT) and the Visual Naming subtest (VNT) of the Multilingual Aphasia Examination. The BNT was diagnostically more sensitive than the VNT in identifying left TLE (77.5% vs 17.5%, respectively). The utility of BNT performance and paraphasias was maximal in patients with Full Scale IQs >or=90 who were 6.8 times more likely to have left TLE than patients without paraphasias. Preoperative assessment of confrontation naming ability and phonemic paraphasia production using the BNT provided diagnostically useful information in lateralizing the epileptogenic region in left TLE.

Stressful life event appraisal and coping in patients with psychogenic seizures and those with epilepsy

Understanding stress and coping among individuals with psychogenic nonepileptic seizures (PNES) may have important treatment implications. 40 patients with PNES, 20 with epilepsy (EPIL), and 40 healthy control (HC) participants reported the frequency of various stressful life events (both positive and negative) and appraised the distress these events induced. They also described their habitual coping behaviors. PNES patients reported no more frequent stressful life events than EPIL patients or HC. In addition, the stressors they experienced are not objectively more severe. However, they reported more severe distress due to negative life events, especially in the domains of work, social functioning, legal matters, and health. PNES patients also engaged in less planning and active coping than HC. Neither of these two coping behaviors was associated with distress ratings. The PNES group did not engage in more denial than either group. However, greater denial among PNES patients was associated with greater perceived distress. Coping in PNES is characterized by elevated levels of perceived distress and fewer action strategies than are normally employed to reduce the impact of a stressor. These findings may inform cognitive behavioral therapy of PNES patients.

Personality Assessment Inventory among patients with psychogenic seizures and those with epilepsy.

The Personality Assessment Inventory (PAI) is a widely used self‐report questionnaire designed to detect and quantify dimensions of adult psychopathology. Previous studies that examined the ability of the PAI to differentiate between patients with psychogenic nonepileptic seizures (PNES) and those with epilepsy (EPIL) have yielded inconsistent results. We compared the full PAI profiles of 62 patients with PNES, 55 with EPIL, and 45 normal control (NC) participants to determine the diagnostic accuracy of the PAI. We also sought to highlight psychopathologic symptoms that may inform psychological treatment of patients with PNES or epilepsy. PNES and EPIL patients reported more somatic concerns and symptoms of anxiety and depression than did NC persons. PNES patients reported more unusual somatic symptoms, as well as greater physical symptoms of anxiety and depression than did patients with EPIL. Classification accuracy of the “NES Indicator” was not much better than chance, whereas the Conversion subscale alone had reasonable sensitivity (74%) and specificity (67%). Overall, the PAI demonstrated only moderate classification accuracy in an epilepsy monitoring unit sample. However, the inventory appears to identify specific psychopathological symptoms that may be targets of psychological/psychiatric intervention.

What Does the Family Pictures Subtest of the Wechsler Memory Scale-III Measure? Insight Gained from Patients Evaluated for Epilepsy Surgery

The Family Pictures (FP) task is a new subtest of the Wechsler Memory Scale Version III (WMS-III) used to assess visual memory and learning. This study assessed the extent to which different cognitive abilities contribute to performance on the FP task in 125 patients evaluated for epilepsy surgery. Results indicated that the FP task relies heavily on auditory-verbal based cognitive abilities, as well as visual memory, and may better represent a general measure of memory performance. These results raise questions about the appropriateness of including FP task performance in the calculations of the WMS-III Visual Index scores.