Influence of consonantal context on the pronunciation of vowels: a comparison of human readers and computational models

In two experiments, we found that college students' pronunciations of vowels in nonwords are influenced both by preceding and following consonants. The predominance of rimes in previous studies of reading does not appear to arise because readers are unable to pick up associations that cross the onset-rime boundary, but rather because English has relatively few such associations. Comparisons between people's vowel pronunciations and those produced by various computational models of reading showed that no model provided a good account of human performance on nonwords for which the vowel shows contextual conditioning. Possible directions for improved models are suggested.     

Sex differences among five sources of motivation in the motivation sources inventory: preliminary findings

Paper reports sex differences among five sources of motivation for a sample of 208 undergraduate students who completed the Motivation Sources Inventory. t tests yielded few statistically significant sex differences for the five sources of motivation; however, Instrumental Motivation was higher among men than women, while the remaining four motives showed no sex difference. Implications and research opportunities are discussed.     

The neural basis of autobiographical and semantic memory: new evidence from three PET studies

A novel, neuropsychologically informed paradigm (extended retrieval of events in response to a cue word) was used to investigate the neural basis of autobiographical and semantic memory. Contrasting retrieval of autobiographical memories with retrieval of semantic facts (ABM-SEM) in 24 subjects across three PET studies revealed bilateral involvement of the middle temporal gyrus (BA 21) and medial frontal cortex (BA 9/10). The opposite contrast, SEM-ABM, resulted in increased regional cerebral blood flow in left posterior temporal regions (BA 37) and left prefrontal cortex (BA 45/46). Laterality maps suggest that the bilateral pattern seen in our studies, but not often in other neuroimaging investigations, reflects the use of a task stressing retrieval of specific personal events. Further comparisons revealed that the activation in the right anterior temporal lobe during autobiographical recall was virtually identical to that seen during retrieval of information about famous people or events in contrast with retrieval of general semantic facts. These findings suggest that the retrieval of an autobiographical event requires participation from conceptual knowledge, and that this type of knowledge is bilaterally distributed in the temporal lobes.     

Direct comparison of episodic encoding and retrieval of words: an event-related fMRI study

Functional magnetic resonance imaging (fMRI) was used to compare directly episodic encoding and retrieval. During encoding, subjects studied visually presented words and reported via keypress whether each word represented a pleasant or unpleasant concept (intentional, deep encoding). During the retrieval phase, subjects indicated (via keypress) whether visually presented words had previously been studied. No reliable differences were found during the recognition phase for words that had been previously studied and those that had not been studied. Areas preferentially active during encoding (relative to retrieval) included left superior frontal cortex, medial frontal cortex, left superior temporal cortex, posterior cingulate, left parahippocampal gyrus, and left inferior frontal gyrus. Regions more active in retrieval than encoding included bilateral inferior parietal cortex, bilateral precuneus, right frontal polar cortex, right dorsolateral prefrontal cortex, and right inferior frontal/insular cortex.     

The PC tachistoscope has 240 pages

Myors (1998) showed how to combine familiar video page switching with bit-plane layering in video mode 0dh to increase the capacity of the PC tachistoscope from 8 to 32 pages. The present article shows how to combine video page switching with color page switching to implement a 240-page tachistoscope, thus producing an almost eightfold increase in the capacity of the PC tachistoscope. The main limitation of this technique is that the images cannot all be located in the same position on the screen. Complete source code in C is included.     

Specificity of disgust sensitivity in the prediction of behavioral avoidance in contamination fear

This study examined the specificity of disgust sensitivity in predicting contamination-related anxiety and behavioral avoidance. Participants high (n=26) and low (n=30) in contamination fear completed self-report measures of disgust sensitivity, contamination cognitions (overestimation of the likelihood and severity of contamination from everyday objects), anxiety, and depression. They then completed three randomly presented contamination-based behavioral avoidance tasks (BATs) that consisted of exposure to a used comb, a cookie on the floor, and a bedpan filled with toilet water. Results indicated that disgust sensitivity was significantly associated with anxious and avoidant responding to the contamination-related BATs. This association remained largely intact after controlling for gender, contamination fear group membership, anxiety, and depression. Contamination cognitions were also significantly related to BAT responses. However, this relationship was fully mediated by disgust sensitivity. These findings indicate that disgust sensitivity has a specific and robust association with contamination concerns commonly observed in obsessive compulsive disorder. The findings are discussed in the context of a disease-avoidance model.     

Learning to control collisions: the role of perceptual attunement and action boundaries

The authors investigated the role of perceptual attunement in an emergency braking task in which participants waited until the last possible moment to slam on the brakes. Effects of the size of the approached object and initial speed on the initiation of braking were used to identify the optical variables on which participants relied at various stages of practice. In Experiments 1A and 1B, size and speed effects that were present early in practice diminished but were not eliminated as participants learned to initiate braking at a rate of optical expansion that varied with optical angle. When size and speed were manipulated together in Experiment 2, the size effect was quickly eliminated, and participants learned to use a 3rd optical variable (global optic flow rate) to nearly eliminate the speed effect. The authors conclude that perceptual attunement depends on the range of practice conditions, the availability of information, and the criteria for success.     

Friend influence over adolescent problem behaviors as a function of relative peer acceptance: to be liked is to be emulated

Friend influence over alcohol intoxication and delinquent behavior was examined as a function of relative peer acceptance in a 3-year study of Swedish youth (N = 184 girls, 145 boys). Participants were in the first year of secondary school (7th grade, M = 11.7 years old) or the first year of high school (10th grade, M = 15.3 years old) at the outset. Friends resembled one another before the friendship; resemblances were even greater after the friendship began. Resemblances continued to grow among those who remained friends one year later, but declined among those whose friendships dissolved. Partners were not equally responsible for increases in similarity. In stable friendships, the more accepted partner exerted greater influence over the less accepted partner, such that the greatest increases in problem behaviors were found among less accepted youth whose friends had higher initial levels of delinquency and alcohol intoxication. Unstable friends resembled random pairs of youth in that more- and less-accepted partners were comparably uninfluential.