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Mark Todd

Publications and source records attributed to Mark Todd.

3 recordsLinked to original sources

Can the MMPI-2 discriminate between mild-moderate TBI and other neurologic and psychiatric populations?

MMPI-2 maintains an extensive empirical base with psychiatric populations, although more recently, neurologically compromised patients have documented unique elevation patterns. This study examined mild-moderate TBI patients, Alzheimer's Dementia patients, and Psychiatric controls on MMPI-2 scales. Participants included 160 outpatients (TBI n = 26, AD n = 74, Psychiatric n = 60). Controlling for family-wise-error, five ANCOVAs were conducted on five MMPI-2 scales, correcting for age and education. TBI and Psychiatric group means were significantly higher than AD group means for scales Hypochondriasis, Depression, and Hysteria at an alpha of .01. Results support previous research with mild TBI patients, and further document a unique pattern of elevations in this population.

Adult↗

Dolphin continuous auditory vigilance for five days.

The present report describes the first study of continuous vigilance in dolphins. Two adult bottlenose dolphins (Tursiops truncatus), WEN (male) and SAY (female), maintained a very high detection rate of randomly presented, infrequent, 1.5-s target tones in a background of frequent 0.5-s equal-amplitude tones over five continuous 120-h sessions. The animals were able to maintain high levels (WEN 97, 87, 99%; SAY 93, 96%) of target detection without signs of sleep deprivation as indicated by behavior, blood indices or marked sleep rebound during 24 h of continuous post-experiment observation. Target response time overall (F = 0.384; P = 0.816) did not change between day 1 and day 5. However, response time was significantly slower (F = 21.566, P = 0.019) during the night (21.00-04.00 h) when the dolphins would have ordinarily been resting or asleep.

Animals↗

Differential performance of Alzheimer's and vascular dementia patients on a brief battery of neuropsychological tests.

The purpose of this article was to examine the differences in neuropsychological test performance between groups with Alzheimer's and vascular dementia. Patients included in this study were those diagnosed with Alzheimer's Disease (AD) or Vascular Dementia (VAD) through a series of neuroradiological tests that included at a minimum a CT or MRI scan and a SPECT scan. Of the 113 AD patients, the average age was 80.08 (SD = 5.91) years and average education was 12.85 (SD = 2.88). Of the 109 VAD patients, average age was 78.67 (SD = 5.35) and average education was 13.10 (SD = 2.65). Tests included selected subtests of the WAIS-R, Word Fluency, Rey Figure, Boston Naming Test, Math, Reading, and subtests from the WMS-R. Five tests showed significant differences in favor of the VAD group: Information, Similarities, Picture Completion, WRAT Mathematics, and the Boston Naming Test. Both groups did well on Reading, while both did poorly on the Rey and Word Fluency. Although both groups did poorly on memory measures, the VAD patients showed better performance. Overall, the two groups did not differ significantly on the more complex tests, but did differ on more basic tests and all the memory tests. This pattern of similar score on complex tests and different scores on basic tests demonstrates the theory that both types of dementia affected higher, more complex skills. Differences between the groups were only apparent when basic skills were compared and were not reflected in more complex and neuropsychologically "sensitive" tests.

Aged↗