Susan McPherson

SENSITIVITY AND SPECIFICITY OF FINGER TAPPING TEST SCORES FOR THE DETECTION OF SUSPECT EFFORT

ABSTRACT Past studies indicate that patients with incentive to fake neuropsychological symptoms are likely to have lower finger tapping scores than credible patients. The present study builds upon past research by investigating finger tapping performance for seven groups: (a) noncredible patients (as determined by failed psychometric and behavioral criteria), and patients with (b) closed head injury, (c) dementia, (d) mental retardation, (e) psychosis, or (f) depression, and (g) healthy older controls. Results showed that men tapped faster than women, requiring that groups be divided by gender. Noncredible male and female patients tapped slower than their comparison group counterparts. Dominant hand score proved to be more sensitive to noncredible performance than other scores (nondominant, sum of both hands, difference between dominant and nondominant), especially for women. Sensitivity, specificity, and positive and negative predictive values tables are presented. With specificity set at 90% for the comparison groups combined, a dominant hand cutoff score of ≤35 for men yielded 50% sensitivity, while a score of ≤28 yielded 61% sensitivity for women. Specificity values for specific cutoff scores varied significantly across the comparison groups, indicating that cutoffs should be adjusted for the particular differential diagnosis. In conclusion, results indicate that when using finger tapping scores to detect noncredible performance: (a) Dominant hand performance is more sensitive, and (b) cutoffs should be selected based on gender and claimed diagnosis.

Apathy and executive function in Alzheimer's disease.

Apathy is a common behavioral disturbance in patients with Alzheimers disease (AD). Recent studies have linked the presence of apathy to alterations in frontal lobe functions, but few studies have explored the relationship using standard neuropsychological measures in patients with AD. We administered a comprehensive battery of neuropsychological tests and a behavior rating scale to 80 patients with AD. We explored the relationship of apathy to executive dysfunction. AD patients with apathy performed significantly worse on tests of executive function (WAIS-R Digit Symbol, Trail-Making, Stroop Color Interference Test) than AD patients without apathy. The presence of dysphoria did not modify these results and no significant relationships were found between tests of executive functions and dysphoria. Performance on executive measures as a group were effective in correctly classifying patients as apathetic or nonapathetic with 75% accuracy. Neuropsychological measures not dependent on executive functions were unrelated to apathy. Apathy is associated with executive dysfunction and not with other neuropsychological deficits. Apathy is distinct from dysphoria.

Relational Integration and Executive Function in Alzheimer's Disease.

Executive functions depend on the ability to represent relations between objects and events, and the prefrontal cortex provides the neural substrate for this capacity. Patients with probable Alzheimers disease (AD) and control participants were administered measures of working memory and reasoning that varied systematically in their relational complexity. AD patients showed impairment on reasoning measures that required the online integration of relations but performed as well as control participants on nonrelational items and items requiring the processing of only single relations. When AD patients were divided into subgroups based on their performance on relational reasoning measures, the subgroup that showed significant impairment on relational integration measures exhibited a neuropsychological profile consistent with prefrontal cortical dysfunction.

Gender-related cognitive deficits in Alzheimer's disease.

Recent studies have identified cognitive deficits in semantic memory and verbal language abilities among women with Alzheimers disease (AD). Few studies to date have explored gender differences in episodic memory function in AD. The present study compared the performance of men and women diagnosed with AD on a battery of neuropsychological measures. Results indicated the presence of gender-related cognitive deficits on tasks of confrontation naming, expressive word knowledge, and both episodic and semantic memory for women with AD, relative to findings in men.

Cognitive performance in relatives of patients with probable Alzheimer disease : an age at onset effect ?

Cognitive performance of 32 siblings and children of patients with probable Alzheimer disease was assessed longitudinally over an interval averaging 4 years. Mean scores were within normal limits for age on all measures at both test times. However, relatives of patients with early-onset dementia (less than or equal to 67 years) were more likely to show a decline in performance from the first to second testing than relatives of patients with late-onset dementia. Additional follow-up will be needed to determine the reliability of performance trajectories and to assess whether mild cognitive changes are related to future dementia. However, findings suggest that it may be important to consider family history of dementia in studies of normal cognitive aging.

Functional ability in executive variant Alzheimer's disease and typical Alzheimer's disease

A frontal, or executive, variant of Alzheimers disease (EAD) has been described in the literature in which frontal dysfunction accompanies temporal and parietal changes in the early stages of the illness. However, no study has empirically investigated associated aspects, such as neuropsychiatric symptoms, instrumental activities of daily living, or caregiver burden in this EAD subgroup. We compared the performance of two subgroups of mild Alzheimers disease patients (e.g., EAD and typical Alzheimers disease; TAD) on neuropsychological and associated measures. Results revealed that the EAD group, selected based on poor executive scores, did not significantly differ from the TAD group on nonexecutive neuropsychological tests of intelligence, language, verbal and nonverbal memory, or visual-spatial abilities. However, the EAD group evidenced more severe neuropsychiatric symptoms, impaired activities of daily living, and greater caregiver distress than the TAD group. Thus, the EAD subgroup is characterized by executive dysfunction, neuropsychiatric symptoms, and functional disability in excess of that seen in TAD. Whether our EAD subgroup represents an actual frontal variant of Alzheimers disease awaits replication in a larger sample including neuroimaging and pathological confirmation, as well as longitudinal assessment of cognition and neuropsychiatric symptoms.

Subjective memory loss in age-associated memory impairment: Family history and neuropsychological correlates

Abstract Self-ratings of everyday memory function and performance on memory tests were examined in 61 first-degree relatives of patients with Alzheimers disease (AD) and 41 matched controls without a family history of dementia. Subjective memory ratings were significantly related to depression scores, despite the low levels of depressive symptoms in this healthy sample. Relatives of patients with early-onset dementia had higher levels of memory complaints compared to control participants, mediated in part by higher levels of depressive symptoms among these relatives. For the sample as a whole, there was little relationship between subjective memory ratings and performance on memory tests, but among early-onset AD relatives, subjective perceptions of memory decline were associated with poorer memory performance.

Self-Reports of Memory Problems in Relatives of Patients With Probable Alzheimer's Disease

This study examined the relationship between subjective memory complaints and performance on tests of memory by relatives of patients with probable Alzheimers disease (AD) and by older adults without a family history of dementia. Relatives of AD patients did not differ significantly from controls either in level of complaint or in performance on neuropsychological tests. However, among relatives of patients with early-onset AD, significant correlations were found between performance on memory tests and self-rated changes in everyday memory. These findings raise the possibility that relatives who have entered the age range in which their parents or siblings developed dementia symptoms are monitoring their memory performance more diligently than relatives of patients whose illness began at much later ages or persons who have no close relatives with AD.

The Satz-Mogel Short Form of the Wechsler Adult Intelligence Scale Revised: Effects of Global Mental Status and Age on Test-Retest Reliability

Abbreviated versions of the Wechsler Adult Intelligence Scale-Revised (WAIS-R) have been developed as time saving devices that provide accurate estimates of overall level of general intellectual functioning while decreasing test administration time. The Satz-Mogel short form of the WAIS-R has received substantial attention in the literature as an accurate measure of intellectual functions when compared with the Full WAIS-R. However, most studies comparing the Satz-Mogel version to the Full WAIS-R have only provided correlational analyses. Our study was an attempt to apply a more rigorous statistical methodology in determining if the Full WAIS-R and abbreviated versions are equivalent. We explored the impact of level of global mental status and age on the Satz-Mogel version. Although the two forms of the test correlated highly, repeated measures design indicated significant differences between Satz-Mogel and Full WAIS-R when participants were divided into groups based on level of global impairment and age. Our results suggest that the Satz-Mogel version of the test may not be equivalent to the full WAIS-R and is likely to misrepresent a patient’s level of intellectual functioning, particularly for patients with progressive degenerative conditions. The implications of applying Satz-Mogel scoring to the Wechsler Adult Intelligence Scale-III (WAIS-III) are discussed.

Neuropsychiatric Symptoms in Alzheimer’s Disease: Assessment and Management

Neuropsychiatric disorders are common in AD and other dementias and reflect changes in brain function. Regional pathological and neurochemical alterations determine the profile of neuropsychiatric symptoms observed in different disorders and among different patients with the same disorder. Clinical trials of agents intended to improve cognition in AD should include behavioral assessment. Behavioral changes may influence cognition, activities of daily living, caregiver burden, and quality of life; neuropsychiatric assessments are needed to understand changes in these domains. The psychotropic effects of anti-AD drugs may be of benefit to AD patients who have no cognitive response to the agents, and behavioral changes may be the primary outcome measures of some trials of anti-AD therapies. Conventional psychotropic agents may benefit patients unresponsive to cholinergic compounds.