Biomedical subjects

Daniel L Drane

Publications and source records attributed to Daniel L Drane.

4 recordsLinked to original sources

PubMed2006

Structured cueing on a semantic fluency task differentiates patients with temporal versus frontal lobe seizure onset.

Patients with frontal lobe dysfunction (e.g., Huntington's disease) reportedly benefit more from cueing on measures of semantic fluency than do patients with damage to temporal lobe structures (e.g., Alzheimer's disease). This differential benefit from cueing suggests that different neurocognitive functions are impaired in these two groups. Patients with frontal lobe dysfunction are presumed to have difficulty with the executive aspects of this generative fluency task, whereas patients with temporal lobe impairment are limited by deficits in semantic memory. We studied the performance of patients with complex partial seizures of frontal or temporal lobe onset, as determined by video/EEG monitoring, on standard and cued measures of semantic fluency administered in a counterbalanced sequence across groups. These groups did not differ significantly in terms of age, education, gender, age at seizure onset, total number of antiepileptic drugs, or IQ, and all patients subsequently underwent surgery for intractable epilepsy. Patients with frontal lobe dysfunction (FL group) performed significantly worse than patients with temporal lobe impairment (TL group) on the standard semantic fluency paradigm (TL group: M=18.4, SD=4.7; FL group: M=11.1, SD=5.3), t(27)=-3.75, P<0.001. Nevertheless, results of an ANCOVA demonstrated that the FL group showed significantly greater performance improvement than the TL group when provided with a cued semantic fluency format, even after controlling for baseline differences in ability on the standard semantic fluency task (TL group: M=0.45, SD=3.8; FL M=9.4, SD=5.1), F(1,29)=12.37, P=0.002. These findings support previous research suggesting that frontal and temporal structures contribute uniquely to semantic generative fluency and suggest that using a combination of standard and cued semantic fluency tasks may help confirm localization of seizure onset in partial epilepsy by localizing the associated cognitive dysfunction.

Adult↗

PubMed2006

Cognitive impairment is not equal in patients with epileptic and psychogenic nonepileptic seizures.

PURPOSE: Patients with psychogenic nonepileptic seizures (PNES) and those with epileptic seizures (ES) purportedly have roughly equal neurocognitive deficits. However, recent findings suggest that patients with somatoform disorders exhibit more variable effort on neurocognitive testing than do controls. We reexamined neurocognitive function in patients with ESs and PNES by using symptom validity testing to control for variability in effort. METHODS: Patients referred for video-EEG monitoring were administered the Word Memory Test (WMT), a measure of symptom validity, as part of neuropsychological evaluation. Patients classified with ictal video-EEG recordings as having ES (n = 41) or PNES (n = 43) were compared on neurocognitive and WMT performance and demographic, psychiatric, and medical variables. RESULTS: Striking rates of WMT failure were observed in the PNES (51.2%) group, but not in the ES (8.1%) group (p = <0.001) after controlling for false-positive errors. Although the PNES and ES groups reported equivalent neurologic histories, the PNES group exhibited less objective evidence of impairment as measured by valid neuropsychological testing, MRI of the brain, and video-EEG monitoring. CONCLUSIONS: Many patients with PNES do not put forth maximal effort during neuropsychological assessment. When patients with PNES put forth valid effort, they demonstrate less objective evidence of neuropathologic injury or disease than do patients with ES. The cognitive impairment reported by this group appears to be more a function of motivational (although not necessarily intentional) factors than of verifiable neuropathology.

Adult↗

PubMed2003

Healthy older adult performance on a modified version of the Cognistat (NCSE): demographic issues and preliminary normative data.

Normative data for a healthy sample of older adults (n = 108) ranging in age from 60 to 96 are provided for the Cognistat, a mental status exam previously known as the Neurobehavioral Cognitive Status Examination (NCSE). A Cognistat Composite Score is also introduced that is intended to be used as a marker of general cognitive impairment, allowing the Cognistat to be used to match patients in terms of the severity of their cognitive dysfunction. The "screen and metric" approach of the Cognistat was abandoned in order to improve the reliability and standardization of this measure by administering the entire metric to all patients. The impact of demographic variables on Cognistat performance was examined, demonstrating that both age and education contribute uniquely to a number of Cognistat subtests as well as to the Cognistat Composite Score. This study highlights the importance of matching an examinee's demographic background to the normative sample with which his or her test score is being compared. Normative data were stratified accordingly by age and by both age and education. Current results indicate that the Cognistat is sensitive to normal aging and promises greater sensitivity to the impact of age than the commonly employed Mini-Mental State Examination (MMSE).

Aged↗

PubMed2002

Demographic characteristics and normative observations for derived-trail making test indices.

OBJECTIVE: The Trail Making Test (TMT) is a psychomotor task that is used routinely in clinical evaluations and consists of two parts: TMT-A and TMT-B. The purpose of the present study was to examine the relations of two derived-TMT indices with age, education, and gender and to establish normative data. BACKGROUND: Prior research has suggested that these derived indices provide purer measures of the executive skills required to complete TMT-B. It has also been suggested that these scores can be effectively used to detect cognitive impairment, and that they are relatively free from the impact of age. METHOD: Difference scores (B minus sign A) and ratio scores (B:A) were computed from the TMT performance of 285 adults who have no history of substance abuse or psychiatric or neurologic disorder and who are not currently being treated with any type of psychotropic medication. RESULTS: Subjects ranged in age from 18 to 90 years and in education level from 6 to 20 years. For the entire sample, (B minus sign A) scores ranged from 6 to 248 seconds (M, 62.15; SD, 49.44), and (B:A) scores ranged from 1.23 to 9.54 (M, 2.81; SD, 1.13). Significant correlations were noted with age and (B minus sign A) and (B:A) scores, accounting for 28% and 6% of the variance, respectively. Subjects were assigned to one of eight age groups, which were formed by decade. Univariate analyses of variance were significant for (B minus sign A) (p < 0.0001) and (B:A) (p < 0.0004) scores. Post hoc analyses indicated that the two oldest age groups had significantly larger (B minus sign A) scores than the younger age groups. However, post hoc analyses with (B:A) scores indicated that only the 70-79-year-old age group significantly differed from the three youngest age groups. No other age groups significantly differed from another on this measure. CONCLUSIONS: Normative data are presented for clinical use, and recommendations are made for future research. In addition, the current results suggest that normal aging has a significant impact on cognitive flexibility and indicate that previous suggestions for impairment cut-off scores based on the (B:A) ratio may result in erroneous classification of healthy older adults.

Adult↗