The association between intelligence level and brain volume measures: a negative finding

Ratings of pre-morbid intelligence level, derived from the hospital charts of 26 chronic schizophrenics, were correlated with the post-mortem brain volume measures of cortex, white matter, central grey matter, and ventricles. Contrary to hypothesis, no significant correlations were found.     

A SURVEY OF MANAGEMENT TRAINING AND EDUCATION PRACTICES IN U.S. COMPANIES

A survey was systematically developed to assess issues related to management training and education, and it was sent to 1,000 randomly selected U.S. companies with at least 1,000 employees. Based on a 61% response rate, findings were obtained regarding issues such as needs assessment, management training and development approaches, reasons for selecting particular programs, characteristics of participants, how decisions are made regarding who will participate, preparation and follow-up of participants, evaluation of management training programs, future management training trends, and needed training content. Significant findings by company size and industry type also are reported.     

IES Arrow Dot performance and success in a cocaine detoxification program

The IES Arrow-Dot was administered to 41 cocaine detoxification patients. This group's scores indicated lower ego functioning and higher impulsivity and superego functioning than other clinical samples. No significant differences were noted between the Arrow-Dot scores of patients who successfully completed the program and those who did not.     

Heart-rate response to water-immersion isolation as a function of spatial orientation

The present study investigates the effect of spatial orientation of the body on heart rate during conditions of water-immersion sensory isolation. Two groups of three men and three women each were exposed to one of two isolation conditions. In one condition the subject was suspended in a buoyant but vertical attitude; in a second condition the subject was suspended in a buoyant but horizontal attitude. Heart-rate data were obtained continuously during each session. There was no significant difference in mean heart rate between the two conditions. The data were interpreted as providing support for the position that studies comparing recumbent subjects in air isolation with underwater subjects in a vertical suspension attitude are valid, at least for some measures, and are not an artifact of spatial bodily orientation. The possible importance of neutral buoyancy in accounting for the nonsignificant effect of body attitude on heart rate is discussed.     

Font regularity constraints on the process of letter recognition

Strings of four unrelated letters were presented for subjects to identify, followed by a patterned mask and then a forced choice test of each letter position. In Experiment 1, the type style in the regular conditions was consistent--all of the letters were of a single type font--whereas in the mixed condition, each string contained letters from two type fonts. Compared with the mixed condition, accuracy in the regular conditions was higher overall and increased at a faster rate as a function of processing time. This held across four sessions. In Experiment 2, the font in the mixed condition was varied either between or within letter strings; sizeable advantages for the regular conditions were found with both mix-methods. The results are consistent with the idea of a schemalike perceptual system that becomes tuned to the regularities of a particular font in order to process visual information efficiently.     

Problem structure and the use of base-rate information from experience

This article is concerned with the use of base-rate information that is derived from experience in classifying examples of a category. The basic task involved simulated medical decision making in which participants learned to diagnose hypothetical diseases on the basis of symptom information. Alternative diseases differed in their relative frequency or base rates of occurrence. In five experiments initial learning was followed by a series of transfer tests designed to index the use of base-rate information. On these tests, patterns of symptoms were presented that suggested more than one disease and were therefore ambiguous. The alternative or candidate diseases on such tests could differ in their relative frequency of occurrence during learning. For example, a symptom might be presented that had appeared with both a relatively common and a relatively rare disease. If participants are using base-rate information appropriately (according to Bayes' theorem), then they should be more likely to predict that the common disease is present than that the rare disease is present on such ambiguous tests. Current classification models differ in their predictions concerning the use of base-rate information. For example, most prototype models imply an insensitivity to base-rate information, whereas many exemplar-based classification models predict appropriate use of base-rate information. The results reveal a consistent but complex pattern. Depending on the category structure and the nature of the ambiguous tests, participants use base-rate information appropriately, ignore base-rate information, or use base-rate information inappropriately (predict that the rare disease is more likely to be present). To our knowledge, no current categorization model predicts this pattern of results. To account for these results, a new model is described incorporating the ideas of property or symptom competition and context-sensitive retrieval.     

Is it smart to play the horses? Comment on "A day at the races: a study of IQ, expertise, and cognitive complexity" (Ceci & Liker, 1986)

Ceci and Liker (1986b) presented data that they contended shows two things: (a) Handicapping harness races is a cognitively complex undertaking that can be captured by a multiple regression model, and (b) neither overall skill at handicapping nor the complexity of the mental model used is related to standard measures of intelligence. The first contention is not at issue. But the second contention, that handicapping performance is unrelated to IQ, is not supported by the data presented; in fact, the opposite conclusion seems more likely. The purpose of this comment is to point out errors frequently made in individual-differences research concerning population definition, sample selection, dependent and independent variable reliability and validity and interpretation of results.     

Chronic sweet intake lowers pain thresholds without changing brain mu- or delta-opiate receptors

Sprague-Dawley rats drank sweetened (3% dextrose + 0.144% saccharin, w/v) or unflavored water for 18 days and subsequent pain reactivity was assessed using a hot plate. Compared to the rats that consumed unflavored water, the rats that consumed sweet water responded more quickly on the hot plate indicating that their threshold for pain was lowered. Another group of rats given identical exposure to the fluids had their brains prepared for measuring opiate receptor binding using the delta-receptor ligand [3H]D-Ala-D-Leu-enkephalin ([3H]DADLE) and the mu-receptor selective ligand [3H]Tyr-D-Ala-Gly-MePhe-Gly-ol ([ 3H]DAGO). Binding of these opiates to mu- and delta-receptors in the cerebral cortex, striatum, hippocampus, hypothalamus, brain stem, and remaining brain regions was the same for the rats that drank sweet fluids and those that drank unflavored water. These findings suggest that drinking sweet fluids lowers pain thresholds but does not alter mu- and delta-receptors.