Depression and cognitive impairment in disability-free early multiple sclerosis

Cognitive and emotional capabilities were evaluated in 73 female patients with stable relapsing-remitting definite, and/or laboratory-supported multiple sclerosis (MS) and were compared with 32 matched healthy controls. Patients were categorized according to their score in the expanded disability status scale (EDSS) to either no (EDSS 0, n = 33) or few clinical signs (EDSS 1-2, n = 40) of MS without physical disability. Patients with EDSS > 0 were characterized by significantly (p < 0.001) higher scores on "von Zerssen's" depression scale, compared to controls. Patients with higher EDSS scores (1-2) showed significantly decreased performance with respect to the total score of Kimura's Recurring-Figures-Test (p < 0.001), in addition. Regarding visuo-constructive functioning, patients with EDSS=0 performed to a significantly lower level (p < 0.001), compared to controls. These results indicate that depression may present as an early sign in MS followed by cognitive impairment, in particular visuo-spatial short-term memory, before physical disability appears. Neuropsychological tests as mentioned here could serve as early diagnostic tools to detect subtle disease progression and to initiate and monitor disease modifying therapies.     

Medical slang in British hospitals

The usage, derivation, and psychological, ethical, and legal aspects of slang terminology in medicine are discussed. The colloquial vocabulary is further described and a comprehensive glossary of common UK terms provided in appendix. This forms the first list of slang terms currently in use throughout the British medical establishment.     

Confirmatory factor analysis of the WMS-III in patients with temporal lobe epilepsy

Five competing models specifying the factor structure underlying the Wechsler Memory Scale-Third Edition (D. Wechsler, 1997b) primary subtest scores were evaluated in a sample of patients with intractable temporal lobe epilepsy (N = 254). Models specifying separate immediate and delayed constructs resulted in inadmissible parameter estimates and model specification error. There were negligible goodness-of-fit differences between a 3-factor model of working memory, auditory memory, and visual memory and a nested--more parsimonious--2-factor model of working memory and general memory. The results suggest that specifying a separate visual memory factor provides little advantage for this sample--an unexpected finding in a population with lateralized dysfunction, for which one might have predicted separate auditory and visual memory dimensions.     

Observing one's hand become anarchic: an fMRI study of action identification

The self seems to be a unitary entity remaining stable across time. Nevertheless, current theorizing conceptualizes the self as a number of interacting sub-systems involving perception, intention and action (self-model). One important function of such a self-model is to distinguish between events occurring as a result of one’s own actions and events occurring as the result of somebody else’s actions. We conducted an fMRI experiment that compared brain activation after an abrupt mismatch between one’s own movement and its visual consequences with an abrupt mismatch between one’s own movement and somebody else’s visually perceived hand movement. A right fronto-parietal network was selectively active during a sudden mismatch between one’s own observed and performed hand action.     

Posthypnotic suggestion and the modulation of Stroop interference under cycloplegia

Recent data indicate that under a specific posthypnotic suggestion to circumvent reading, highly suggestible subjects successfully eliminated the Stroop interference effect. The present study examined whether an optical explanation (e.g., visual blurring or looking away) could account for this finding. Using cyclopentolate hydrochloride eye drops to pharmacologically prevent visual accommodation in all subjects, behavioral Stroop data were collected from six highly hypnotizables and six less suggestibles using an optical setup that guaranteed either sharply focused or blurred vision. The highly suggestibles performed the Stroop task when naturally vigilant, under posthypnotic suggestion not to read, and while visually blurred; the less suggestibles ran naturally vigilant, while looking away, and while visually blurred. Although visual accommodation was precluded for all subjects, posthypnotic suggestion effectively eliminated Stroop interference and was comparable to looking away in controls. These data strengthen the view that Stroop interference is neither robust nor inevitable and support the hypothesis that posthypnotic suggestion may exert a top-down influence on neural processing.     

Lesions of orbitofrontal cortex and basolateral amygdala complex disrupt acquisition of odor-guided discriminations and reversals

Recent work indicates that both orbitofrontal cortex (OFC) and the basolateral complex of the amygdala (ABL) are involved in processes by which cues are associated with predicted outcomes. To examine the respective roles of these structures in discrimination learning, rats with bilateral sham or neurotoxic lesions of either OFC or ABL were trained on a series of four 2-odor discrimination problems in a thirst-motivated go, no-go task. After acquisition of the series of odor problems, the rats were trained on serial reversals of the final odor problem. Performance on each problem was assessed by monitoring accuracy of choice behavior, and also by measuring latency to respond for fluid outcomes after odor sampling. During discrimination learning, rats in both lesioned groups had similar deficits, failing to show normal changes in response latency during learning, while at the same time exhibiting normal choice behavior relative to controls. Choice behavior was affected only during the reversal phase of training, in which OFC and ABL lesions produced distinctive deficits. Rats with ABL lesions were impaired on the first reversal (S1−/S2+), but were unimpaired at acquiring a reversal back to the original odor-outcome contigencies (S1+/S2−), whereas rats with OFC lesions were impaired on both types of reversals. These findings suggest that OFC and ABL serve partially overlapping roles in the use of incentive information that supports normal discrimination performance.     

Human nonverbal counting estimated by response production and verbal report

In three experiments, people were shown sequential displays and were prevented from verbal counting by being required to perform other cognitive tasks. In Experiment 1, the subjects were shown three 1.target (target5 = 8, 16, or 32) sequences of colored geometric shapes. On occasional question trials, the subjects were asked to estimate the target number after the final item in the sequence. On other test trials, items continued to appear beyond the target, and the subjects estimated the target manually by tapping a space bar. In Experiments 2 and 3, a matching-to-sample procedure required the subjects to estimate the same sequence of items (target = 8, 11, 14, 17, or 20) both verbally and manually. The results indicated that (1) manual and verbal estimates closely approximated target size in Experiments 1 and 2, (2) coefficients of variation were constant across target size, and (3) correlations between manual and verbal estimates were positive in Experiments 2 and 3. Requiring the subjects to perform a counting task during presentation of items led to underestimation of number in Experiment 3. nt]mis|This research was funded by a research grant from the Natural Sciences and Engineering Research Council of Canada to W.A.R. and by the Ontario Graduate Scholarship in Science and Technology and the Ontario Graduate Scholarship to M.J.B.     

Cost-effectiveness and test-performance factors in relation to universal newborn hearing screening

The first portion of this paper reviews current understanding of the cost of universal newborn hearing screening (UNHS), including capital and operating expenses, as well as the costs for follow-up testing on infants who do not pass the hearing screening test in the perinatal period. Capital expenses include the cost of equipment. Operating expenses include the costs for disposables and personnel. Follow-up costs relate to the diagnostic testing that must be performed in order to determine hearing status in those infants who do not pass the newborn hearing screening test. This section is followed by a more theoretical approach, in which test performance, prevalence, program costs, and "costs of hearing loss" are combined in a model that includes all costs of hearing loss, including screening, follow-up testing, and costs (benefits) associated with identifying hearing loss early in life. While some of the model's cost/benefit assumptions may be incorrect, the general approach of taking into account both costs and benefits provides a framework for evaluating the utility of UNHS in a more global manner. Model assumptions (costs, benefits, prevalence, sensitivity, specificity) can be changed to values deemed more appropriate, but the general approach is still informative. With the present assumptions, it is shown that initially, the costs of UNHS exceed its benefits. However, after only four years of operation, UNHS programs will result in a net savings to society. These savings increase rapidly, reaching a maximum annual benefit of seven billion dollars 75 years after initiation of the program, which is also the societal benefit for all years thereafter.