Differential prefrontal-temporal neural correlates of semantic processing in children

This study used functional magnetic resonance imaging (fMRI) to examine brain-behavior correlations in a group of 16 children (9- to 12-year-olds). Activation was measured during a semantic judgment task presented in either the visual or auditory modality that required the individual to determine whether a final word was related in meaning to one of two previous words (e.g., found-tank-lost). The main finding was that higher performers (i.e., accuracy) were associated with more activation in posterior representational systems including the inferior and middle temporal gyri, whereas lower performers were associated with more activation in anterior regions including the inferior and middle frontal gyri. This pattern of results was interpreted as reflecting an elaborated semantic representational system in temporal areas for the high accuracy performers that allowed them to efficiently and accurately make meaning based judgments. The low accuracy performers may have an inaccurate or weakly interconnected semantic system that results in greater use of frontal areas in a feature selection process.     

What is the relationship between synaesthesia and visuo-spatial number forms?

This study compares the tendency for numerals to elicit spontaneous perceptions of colour or taste (synaesthesia) with the tendency to visualise numbers as occupying particular visuo-spatial configurations (number forms). The prevalence of number forms was found to be significantly higher in synaesthetes experiencing colour compared both to synaesthetes experiencing taste and to control participants lacking any synaesthetic experience. This suggests that the presence of synaesthetic colour sensations enhances the tendency to explicitly represent numbers in a visuo-spatial format although the two symptoms may nevertheless be logically independent (i.e. it is possible to have number forms without colour, and coloured numbers without forms). Number forms are equally common in men and women, unlike previous reports of synaesthesia that have suggested a strong female bias. Individuals who possess a number form are also likely to possess visuo-spatial forms for other ordinal sequences (e.g. days, months, letters) which suggests that it is the ordinal nature of numbers rather than numerical quantity that gives rise to this particular mode of representation. Finally, we also describe some consequences of number forms for performance in a number comparison task.     

Renewal of cue-elicited urge to smoke: implications for cue exposure treatment

The effects of cue exposure therapy are limited, because renewal after extinction is an important source of relapse. In this study, 33 smokers were exposed to a cue predicting smoking availability and a cue predicting smoking unavailability in one context (acquisition context A). Following extinction in another context (extinction context B), a test for renewal took place in the original acquisition context A (i.e. ABA renewal). Urge to smoke was measured using a Visual Analogue Scale. Renewal of differential conditioned urge responding occurred when participants were tested in the acquisition context, while differential urge responding remained extinguished when tested in the extinction context. This experiment provides evidence that ABA renewal occurred in smokers. Clinical implications are discussed.     

Consequences of lexical stress on learning an artificial lexicon

Four experiments examined effects of lexical stress on lexical access for recently learned words. Participants learned artificial lexicons (48 words) containing phonologically similar items and were tested on their knowledge in a 4-alternative forced-choice (4AFC) referent-selection task. Lexical stress differences did not reduce confusions between cohort items: KAdazu and kaDAzeI were confused with one another in a 4AFC task and in gaze fixations as often as BOsapeI and BOsapaI. However, lexical stress did affect the relative likelihood of stress-initial confusions when words were embedded in running nonsense speech. Words with medial stress, regardless of initial vowel quality, were more prone to confusions than words with initial stress. The authors concluded that non-initial stress, particularly when wor segmentation is difficult, may serve as "noise" that alters lexical learning and lexical access.     

The structure of frontoparallel haptic space is task dependent

In three experiments, we investigated the structure of frontoparallel haptic space. In the first experiment, we asked blindfolded participants to rotate a matching bar so that it felt parallel to the reference bar, the bars could be at various positions in the frontoparallel plane. Large systematic errors were observed, in which orientations that were perceived to be parallel were not physically parallel. In two subsequent experiments, we investigated the origin of these errors. In Experiment 2, we asked participants to verbally report the orientation of haptically presented bars. In this task, participants made errors that were considerably smaller than those made in Experiment 1. In Experiment 3, we asked participants to set bars in a verbally instructed orientation, and they also made errors significantly smaller than those observed in Experiment 1. The data suggest that the errors in the matching task originate from the transfer of the reference orientation to the matching-bar position.     

One hundred and fifty years of philosophy

Looking back from 2049 over one-hundred and fifty years of philosophy, a student's essay reveals what became of rival strands in Western philosophy – with a sidelong glance at the special Topoi issue on the theme “Philosophy: What is to be Done?” that was published almost half a century earlier.     

Memory comparison time for complex digit stimuli: The effect of number length

Woodworth (1938) reported that naming latency increased linearly with the number of digits per number (number length). In the present study, the Sternberg memory scanning paradigm was utilized to investigate this effect. It was found that the slope of the memory scanning function increased linearly with number length: memory scanning time was 40 msec for one-digit numbers, 70 msec for two-digit numbers and 101 msec for 3 digit numbers. The intercepts of the memory scanning functions did not differ for the three types of numbers. Thus the increase in latency may be due to the memory comparison stage of processing. The data suggest that a memory comparison operation occurs for each digit position of the complex memory items composed of more than one digit.     

Instructed versus pharmacological effects of alcohol in alcoholics and social drinkers

Twelve alcoholics and 12 social drinkers were studied in an experiment where instructions about alcohol or placebo were orthogonally crossed with administration of alcohol or placebo in a Balanced Placebo Design. Three subjects were simultaneously observed while watching soccer games on the TV together and having free access to a mixed drink, which in the alcohol conditions contained 150ml of 80% proof vodka. The assessment procedure included several aspects of drinking behavior, behavioral observations during the session, psychiatric ratings and nurse observations before and after each session, ratings for craving, self-reported state anxiety and physiological changes (heart rate and blood pressure). In general, the results showed the alcoholic's behavior to be controlled by instruction-induced expectancies rather than by the actual beverage given, whereas the social drinkers showed tendencies in the opposite direction. The implications of these results for the traditional disease conception of alcoholism and for learning theory approaches are discussed.