Behavioral complications of early pallidotomy

A review of stereotactic medial pallidotomy of the 1950s in five neurosurgical centers is presented. The surgical technique varied from one center to the other. The results of surgery, however, seemed to be quite equal, being positive in 70-90% of the patients. The surgical mortality ranged from 0 to 13%. Behavioral complications were adequately analyzed and reported from one center only and published by three independent neurologists. The side effects included drowsiness (12%), confusion (13.6%), mental deterioration (5%), memory deficit (13.6%), and dysphasia (7.5-24%, the rate depending on the concomitant brain atrophy). Among permanent side effects, 5% of the patients presented with a mild postoperative mental deterioration, whereas 13.6% had a severe memory deficit. In the four other centers, the results and side effects were analyzed only by the surgeons and were more biased. A comparison of the results and complications between Leksell's early medial pallidotomy of 1951-1957 and recent medial pallidotomies of the 1990s from two centers showed that 40 years ago Leksell had at least as good results as, and less serious complications than, two representative neurosurgeons of today. Even when positive clinical results of GPi pallidotomy have recently been reported from several centers, the patients seem to have improved relatively little, the dyskinesias excepted, and the rate of side effects has been quite high. The author is afraid that medial pallidotomy will soon be abandoned as a method of choice in the surgical treatment of Parkinson's disease, as in fact happened 40 years ago. One should look for better surgical alternatives and targets outside of the medial pallidum.     

Varying intertrial interval reveals temporally defined memory deficits and enhancements in NTAN1-deficient mice

The N-end rule is one ubiquitin-proteolytic pathway that relates the in vivo half-life of a protein to the identity of its N-terminal residue. NTAN1 deamidates N-terminal asparagine to aspartate, which is conjugated to arginine by ATE1. An N-terminal arginine-bearing substrate protein is recognized, ubiquitylated by UBR1/E3α, and subsequently degraded by 26S proteasomes. Previous research showed that NTAN1-deficient mice exhibited impaired long-term memory in the Lashley III maze. Therefore, a series of studies, designed to assess the role of NTAN1 in short- and intermediate-term memory processes, was undertaken. Two hundred sixty mice (126 −/−; 134 +/ +) received Lashley III maze training with intertrial intervals ranging from 2–180 min. Results indicated that inactivation of NTAN1 amidase differentially affects short-, intermediate-, and long-term memory.     

The effects of averaging subjective probability estimates between and within judges

The average probability estimate of J > 1 judges is generally better than its components. Two studies test 3 predictions regarding averaging that follow from theorems based on a cognitive model of the judges and idealizations of the judgment situation. Prediction 1 is that the average of conditionally pairwise independent estimates will be highly diagnostic, and Prediction 2 is that the average of dependent estimates (differing only by independent error terms) may be well calibrated. Prediction 3 contrasts between- and within-subject averaging. Results demonstrate the predictions' robustness by showing the extent to which they hold as the information conditions depart from the ideal and as J increases. Practical consequences are that (a) substantial improvement can be obtained with as few as 2-6 judges and (b) the decision maker can estimate the nature of the expected improvement by considering the information conditions.     

Dyskinesias differentiate autistic disorder from catatonia

Autistic disorder and catatonia are neuropsychiatric syndromes defined by impairments in social interaction, communication, and restricted, stereotypical motor routines. Assessments of children with these disorders are typically restricted in scope by the patients' limited ability to comprehend directions. The authors performed systematic assessments of dyskinesias on six prepubertal boys with autistic disorder and mental retardation and on one adolescent male with catatonia to determine if this type of information could be routinely obtained. The boys with autistic disorder had more stereotypies and tics, a greater degree of akathisia and hyperactivity, and more compulsions than the adolescent with catatonia. Catatonia was associated with catalepsy and dystonic postures. The authors conclude that the diagnostic accuracy and specificity of neuropsychiatric syndromes may be enhanced by the systematic assessment of the dyskinesias associated with each condition.     

The use of genetic test information in insurance: The argument from indistinguishability reconsidered

In the bioethical literature, discrimination in insurance on the basis of genetic risk factors detected by genetic testing has been defended and opposed on various ethical grounds. One important argument in favour of the practice is offered by those who believe that it is not possible to distinguish between genetic and non-genetic information, at least not for practical policy purposes such as insurance decision-making. According to the argument from indistinguishability, the use of genetic test information for insurance purposes should be permitted, because genetic test information is no different from non-genetic medical information in any relevant respect, therefore it would be inconsistent to prohibit the former whilst permitting the latter. This paper discusses and defends this argument and suggests a new, more tenable foundation.     

Mean response times, variability, and skew in the responding of ADHD children: a response time distributional approach

Response time (RT) distributions from three fixed foreperiod conditions (2, 4, and 8 s) in a warned four-choice RT task were obtained for a group of boys with attention-deficit/hyperactivity disorder, combined type (ADHD; n = 17) and for two groups of normal control boys (age-matched, n = 18, and younger-aged, n = 10). Quantitative measures of distributional shape were derived by fitting the ex-Gaussian distributional model to the individual RT data. Statistical results indicate that the ADHD distributions differ from the age-matched control distributions with respect to the size of the tail (larger for the ADHD boys), but differ from the younger control distributions with respect to the location of the leading edge (slower for the younger control boys). Receiver operating characteristic (ROC) results reveal that the ex-Gaussian exponential component is highly diagnostic of the ADHD boys.     

"You have to have somebody watching your back, and if thats God, then thats mighty big": the church's role in the resilience of inner-city youth

This study was designed to explore Freeman's (1986) finding that the institution that made the greatest contribution to male African-American youths' socioeconomic success was the church. Thirty-two African-American, Haitian-American, and Latino male and female teenagers--16 drawn from inner-city Protestant churches and 16 comparison teenagers from the same communities-were interviewed. The interviews revealed that churched teenagers were less stressed and less likely to have psychological problems than were teenagers in the comparison group. They also appeared more likely to be living with both biological parents, less likely to have a family member on welfare, and more likely to have a job when compared with the other teenagers. They described the church as being central to their lives and as having multiple functions, many of which have been identified in the resilience literature as contributing to positive developmental outcomes. Results are interpreted in light of the transactional model, and recommendations are made, such as expanding the role of the church within these ethnic communities.     

Subjective organization and the visibility of illusory contours

The effects of the differential organization of a Necker cube on the perceived salience of an embedded illusory triangle were examined. Overall figural salience was greater when the triangle appeared to be localized on the front rather than the back cube face. Illusory contour salience also increased with increasing inducing area contrast and was greater when the figure was oriented on cardinal as compared to oblique coordinates. However, the latter effects were independent of perceived location within the cube. The finding that subjective organizational and structural factors influenced the perceived salience of the illusory figure but did not interact is consistent with van Tuijl and Leeuwenberg's (1982) suggestion that top-down and bottom-up determinants can operate independently in illusory contour perception.     

The task-specific nature of domain-general reasoning

This paper develops a theory of how interpretative processes constrain inferential performance on conditional reasoning tasks. Experiment 1 investigated the hypothesis that performance on common reasoning tasks is mediated by different interpretive variables. Necessity and sufficiency relations predicted performance on the conditional arguments task, whereas on the Wason task, performance was predicted by whether the conditional statement instantiated a deontic or a factual relation. Performance on the truth-table task was predicted by both sets of variables. Experiment 2 explored the mapping relation between interpretation, representation, and inference. It was observed that conditional responses to the Wason and arguments tasks were based on different representations of the conditional relationship. These data rule out a simple model of the interplay between interpretation and reasoning in which the interpretation of a statement is driven solely by its content, and instead, indicate that the interpretation of conditional relations is task-specific.