Emotional variables and neuropsychological test performance

Although previous studies have demonstrated the general success of neuropsychological tests in discriminating brain-impaired patients from normals and patients with psychiatric disorders, limited attention has addressed the more specific effects of emotional disturbance on test performance. This study investigated MMPI correlates of Halstead-Reitan test (HRB) performance in a sample of 105 neuropsychological referrals (predominantly psychiatric) who had negative neurologic findings. The results indicated significant effects for age and education on many of the tests, with smaller but statistically significant relationships between the quality of HRB test performance and MMPI scores.     

Depression and neuropsychological test performance in acute spinal cord injury patients: lack of correlation.

Factors which have been causally related to neuropsychological deficits in acute spinal cord injury (SCI) patients include advanced age, limited educational level, acute traumatic brain injury, alcohol and/or substance abuse. Concomitant depression may impair motivation, prolong reaction time, and produce fatigue during neuropsychological testing, resulting in impaired performance. To test the hypothesis that abnormal neuropsychologic test results may be associated with depression, the Zung Self-Rating Depression Scale (ZUNG) and a comprehensive, predominantly motor-free neuropsychological test battery were administered to 66 acute SCI patients approximately 8 weeks following injury. Spinal cord injury groups were dichotomized based on their ZUNG scores. Comparison of neuropsychological test scores between SCI groups failed to demonstrate any impairment in neuropsychological performance, within the limits of the test battery administered, suggesting that cognitive performance in this sample of acute SCI patients may not be influenced by the presence of depression.     

Enhanced memory performance on an internal-internal source monitoring test following acute psychosocial stress

Research on the effect of acute stress and high levels of glucocorticoids on memory has largely focused on memory tasks involving the medial temporal lobe (e.g., declarative memory). Less is known, however, about the effects of stress and glucocorticoids on more strategic memory processes regulated by the prefrontal cortex (e.g., source monitoring). In the current study, the authors investigated whether exposure to acute psychosocial stress would result in altered source monitoring performance relative to the performance of a nonstressed control group. To this end, the authors assigned nonsmoking, healthy, young men to either a stress (n = 22) or a control (n = 18) condition, after which the men were given an internal source monitoring test. Results show that relative to control participants, stressed participants made fewer source monitoring errors. This study suggests that stress may have differential effects on memory, depending on whether the memory test is regulated by the prefrontal cortex or the medial temporal lobe.     

Relationship between reaction time and neuropsychological test performance.

Reaction time (RT) has been used to discriminate individuals with brain damage from controls, but little is known about the relationship between RT and neuropsychological (NP) tests. This relationship was examined 3 ways. First, the mean, median, and SD scores of simple and choice RT for 213 referrals were used as potential predictors of NP impairment in discriminant analyses; cross-validation produced a significant hit rate. Second, the hit rate (NP impairment vs. no) using RT was compared to hit rates using fluency, IQ, and memory measures; the RT rate did not significantly exceed the others. Third, the abilities of RT and of a NP impairment score to classify 28 subjects into brain injury and control groups were compared; the hit rates were not significantly different. Results are interpreted to indicate moderate agreement between RT and NP tests regarding impairment classifications and to suggest roles for RT in NP assessment.     

Psychophysiological activity and neuropsychological test performance in alcoholics.

This study examined electromyogram (EMG) and skin conductance level (SCL) as mediators of neuropsychological test performance of alcoholics. Alcoholics and controls with high EMG performed less well than low EMG subjects on 12 measures of neuropsychological performance. For SCL, the alcoholics and controls in the Low Group did not differ from those in the High Group on any measure. Analyses that used information intake (Low EMG and High SCL) and rejection (High EMG and Low SCL) information postures (IPs) demonstrated that the intake group outperformed the rejection group on 10 neuropsychological measures. Subjects with intake IPs reported more stimulation, concentration, and interest during the tasks than did subjects with rejection IPs. Results suggest that IPs can be used to identify alcoholics with neuropsychological deficits.     

The effect of effort on baseline neuropsychological test scores in high school football athletes

ObjectivePoor effort on baseline neuropsychological tests is expected to influence interpretation of post-concussion assessment scores. Our study examined effort in an athletic population to determine if poor effort effects neuropsychological test performance.MethodsHigh school athletes (N = 199) were administered a brief neuropsychological test battery, which included the Dot Counting Test (DCT) and the Rey 15-Item Test with recognition trial. One-way analyses of variance were used to compare groups with adequate and poor effort test performance.ResultsMost athletes (N = 177; 89%) exerted adequate effort while a number of athletes (N = 22; 11%) exerted poor effort on the DCT. Statistically significant differences existed between effort groups (p < 0.05) on several of the neuropsychological tests.ConclusionsPoor effort was observed in the athletic population during baseline testing and athletes with poor effort displayed statistically significant differences in performance on neuropsychological tests. Adding an effort test to baseline examinations may improve post-concussion test score interpretations.     

The relation of neuropsychological test performance to performance of functional tasks in dementia of the Alzheimer type

Canonical analysis was used to related a battery of neuropsychological tests to a set of functional tasks in a sample of 126 healthy older adults and individuals with a clinical diagnosis of dementia of the Alzheimer type. The functional tasks included activities that ranged from relatively simple motoric functions to much more cognitively demanding abilities. In general, functional behavior was substantially correlated with neuropsychological test performance. With the exception of well-routinized motor activities that probably represent procedural memory, both functional tasks and neuropsychological tests appear to assess the same global cognitive deterioration that characterizes Alzheimer's disease.     

The intermediate visual and auditory continuous performance test as a neuropsychological measure.

The Intermediate Visual and Auditory (IVA) Continuous Performance Test (CPT) and Neuropsychological Impairment Scale (NIS) were completed with adults diagnosed with mild traumatic brain injury (mTBI), adults diagnosed with Attention Deficit Hyperactivity Disorder (ADHD), and controls. On the IVACPT, the mTBI and ADHD groups performed significantly lower on the full and secondary scales for attention and response accuracy. For individual scales, the mTBI and ADHD groups showed lower performance on measures of reaction time, inattention, impulsivity, and variability of RT. The mTBI and ADHD groups showed similar patterns of performance on the IVA. On the NIS, the mTBI and ADHD groups reported more neuropsychological symptoms than the control group and the mTBI group reported more neuropsychological symptoms than the ADHD group. The results are discussed in regard to changes in cognitive processing and sustained attention in individuals diagnosed with mTBI and ADHD.     

The effect of post-exercise hydrotherapy on subsequent exercise performance and heart rate variability

We investigated the effect of hydrotherapy on time-trial performance and cardiac parasympathetic reactivation during recovery from intense training. On three occasions, 18 well-trained cyclists completed 60 min high-intensity cycling, followed 20 min later by one of three 10-min recovery interventions: passive rest (PAS), cold water immersion (CWI), or contrast water immersion (CWT). The cyclists then rested quietly for 160 min with R–R intervals and perceptions of recovery recorded every 30 min. Cardiac parasympathetic activity was evaluated using the natural logarithm of the square root of mean squared differences of successive R–R intervals (ln rMSSD). Finally, the cyclists completed a work-based cycling time trial. Effects were examined using magnitude-based inferences. Differences in time-trial performance between the three trials were trivial. Compared with PAS, general fatigue was very likely lower for CWI (difference [90% confidence limits; −12% (−18; −5)]) and CWT [−11% (−19; −2)]. Leg soreness was almost certainly lower following CWI [−22% (−30; −14)] and CWT [−27% (−37; −15)]. The change in mean ln rMSSD following the recovery interventions (ln rMSSD_Post-interv) was almost certainly higher following CWI [16.0% (10.4; 23.2)] and very likely higher following CWT [12.5% (5.5; 20.0)] compared with PAS, and possibly higher following CWI [3.7% (−0.9; 8.4)] compared with CWT. The correlations between performance, ln rMSSD_Post-interv and perceptions of recovery were unclear. A moderate correlation was observed between ln rMSSD_Post-interv and leg soreness [r = −0.50 (−0.66; −0.29)]. Although the effects of CWI and CWT on performance were trivial, the beneficial effects on perceptions of recovery support the use of these recovery strategies.     

Visual reaction time and its relationship to neuropsychological test performance.

The purpose of this study was to investigate the relationship between simple and choice reaction time (RT) measures and neuropsychological test performance (as assessed by the Impairment Index of the Halstead-Reitan Neuropsychological Test Battery). Both median RT scores and intraindividual variability of RT scores were evaluated in three groups: impaired TBI, nonimpaired TBI, and normal controls. In all three groups, there was a statistically significant correlation between both reaction time measures and level of cognitive functioning. In addition, SRT, speed of information processing (as measured by CRT), and intraindividual variability of RT scores continued to be impaired in many brain-damaged individuals who, according to the Impairment Index, had fully recovered from their cognitive deficits. Median RT scores were better able to discriminate between impaired TBI patients and normal controls; but intraindividual variability of RT scores was better able to discriminate between nonimpaired TBI patients and normal controls. It was concluded that, by adding the two short RT tests to the neuropsychological test battery, more accurate predictions can be made about a patient's level of cognitive functioning and the nature of treatment needed for continued recovery.     

The potentiating effect of low oxygen tension exposure during training on subsequent cardiovascular performance

Summary The effect of exhaustive bicycle ergometer training in hypoxia (FIO₂ 0.110–0.125) on several cardiovascular parameters was measured in an Olympic oarsman by serial measurements made daily over a period of 3 months. The hypoxic training had a potentiating effect on ventilation and oxygen uptake both of which attained upper limiting values in all-out tests at the end of one month of training. Acid-base balance changes were measured from arterialized capillary blood and showed a decreasing negative base excess (BE) and low pH response to exhaustive exercise. It has been hypothesized that once maximum oxygen intake ability has been developed an additional training effect was shown either by an increasing buffering capacity to non-volatile acid or by improved oxygen transport at tissue level so that there was a diminished need for an exergonic process of the type glycogen to lactic acid. The effect of interposing normoxic training during the middle month of the whole exercise period negatively affected exhaustive tests in hypoxia but had much less effect on the rate of improvement in exhaustive normoxic tests.     

Meta-analysis of intellectual and neuropsychological test performance in attention-deficit/hyperactivity disorder

Cognitive measures are used frequently in the assessment and diagnosis of attention-deficit/hyperactivity disorder (ADHD). In this meta-analytic review, the authors sought to examine the magnitude of differences between ADHD and healthy participants on several commonly used intellectual and neuropsychological measures. Effect sizes for overall intellectual ability (Full Scale IQ; FSIQ) were significantly different between ADHD and healthy participants (weighted d =.61). Effect sizes for FSIQ were significantly smaller than those for spelling and arithmetic achievement tests and marginally significantly smaller than those for continuous performance tests but were comparable to effect sizes for all other measures. These findings indicate that overall cognitive ability is significantly lower among persons with ADHD and that FSIQ may show as large a difference between ADHD and control participants as most other measures.     

The effects of acute test anxiety on NBME Part I performance.

This study examined the associated effects of acute test-taking anxiety on the performance of a class of second-year medical students who took Part I of the National Board of Medical Examiners (NBME) Examination. The study is a follow-up of a previous study that examined the related effects of chronic anxiety on NBME Part I performance. The purpose of this study was to observe whether there was a relationship between acute anxiety and NBME performance and, further, if there were distinguishable differences in the effects of acute and chronic test anxiety on NBME performance. The first study indicated a significant relationship between chronic anxiety and NBME performance. The results of the present study indicate a relationship between acute test anxiety and NBME performance, but not to the extent associated with chronic anxiety, thus chronic test anxiety may be a more critical factor affecting test performance on critical examinations such as the NBME. Implications concerning anxiety and test performance are discussed.     

The influence of cognitive reserve on neuropsychological functioning following coronary artery bypass grafting (CABG).

Neuropsychological impairment is common, yet variable, after coronary artery bypass grafting (CABG). Similar variability has been observed in other CNS-related diseases. Empirical findings in Alzheimer's disease and HIV, among other areas, suggest cognitive reserve (CR) may mediate the cognitive impact of these diseases. The present study examined whether CR mediates neuropsychological outcome after CABG. Participants were 42 (N=42) individuals who underwent elective, normothermic CABG. Each was placed in high (n=22) or low (n=20) CR groups based on estimated premorbid intelligence and occupational attainment. All were administered neuropsychological tests preoperatively and at discharge. The total incidence of neuropsychological decline (66.7%) was not significantly different between CR groups. However, on working memory and executive function tests, specifically, the high CR group demonstrated greater post-operative decline compared to the low CR group. These data are considered in the context of a threshold model of CR theory.     

Ethnic differences in functional and neuropsychological test performance in older adults.

Numerous studies outline discrepancies in neuropsychological test profiles in African American and European American samples, despite similarities on major background factors. In our clinical sample of convenience, African American and European American older adults did not diverge on age, years of formal education, or global cognitive impairment. We predicted that ethnic groups would differ on a financial index, reading, and naming measures, but not on form discrimination and health problem-solving tasks. Results showed the expected patterns with the exception of form discrimination, which was lower in the African American group. Ethnicity no longer predicted standing on financial and nonverbal discrimination measures once we adjusted scores to equate for word-reading ability. In contrast, ethnicity status continued to explain significant variance in confrontation naming following adjustment for reading. When ethnic groups were subdivided by sex, European American men tended to have the highest scores of all four subgroups despite having equivalent levels of education. Therefore, future studies should examine the impact of cognitive activity throughout adulthood on real-world function and neuropsychological test performance among groups defined by both ethnicity and sex. In conclusion, in African American and European American elders seen for clinical assessment, literacy appeared to be associated with discrepant scores on a measure of real-world financial knowledge and skill, as well as with differences in verbal and nonverbal neuropsychological measures.