Self-reported changes in subjective health and anthrax vaccination as reported by over 900 Persian Gulf War era veterans

A 1999 study of United Kingdom servicemembers by Unwin, et al. recently found significant relationships between anthrax and other vaccinations, reactions to those vaccines, and later health problems for male current or former active military Gulf War veterans. Likewise, in 2000 Steele and in 1998 Gilroy found possible adverse effects of vaccinations on Gulf War veterans. However, the role of such vaccinations remains controversial; more recent government reports continue to dispute the existence of any data that might reflect adversely on the role of vaccinations on the health of Gulf War veterans. To address this controversy, the current study assessed similar relationships for over 900 Reserve Component Gulf War Era veterans from Ohio and nearby states. Gulf War veterans were more likely to report poorer health than non-Gulf veterans. Female veterans were more likely to report mild or severe reactions to vaccines than male veterans. Those veterans who received anthrax vaccine reported more reactions to vaccines than those who did not receive anthrax vaccine. Declines in long-term subjective health were associated with receipt of anthrax vaccine by Gulf War veterans but not for those who did not deploy to the Gulf, although few of the latter received anthrax vaccine. Regardless of deployment status, veterans who reported more severe reactions to vaccines were more likely to report declines in subjective health. Female veterans reported poorer health during the Gulf War than did male veterans, but sex was not related to veterans' reports of subjective health at subsequent times. It is recommended that servicemembers who experience severe reactions to anthrax vaccine be medically reevaluated before receiving further anthrax vaccine and that careful follow-ups be conducted of those receiving the vaccine currently, in accordance with Nass's 1999 recommendations. We also recommend that safer alternatives to thimerosal (a mercury sodium salt, 50% mercury) be used to preserve all vaccines.     

Liking and attributions of motives as mediators of the relationships between individuals' reputations,helpful behaviors,and raters' reward decisions

Two studies investigated the mediating effects of liking and attributions of motives on the relationship between a ratee's reputation and helpful behaviors and raters' reward decisions. During managerial simulations, raters evaluated individuals after watching videotapes in which the individual's reputation and helpful behaviors were manipulated. Results indicated an interaction effect between reputation and helpful behaviors such that a helpful person with a good reputation received more rewards than did a helpful person with a bad reputation. In contrast, an unhelpful person with a good reputation did not receive better rewards than an unhelpful person with a bad reputation. Moreover, raters' liking of ratees and the motives raters attributed to ratees' helpful behaviors mediated the relationship between the manipulations and raters' reward decisions.     

Knowledge partitioning in categorization: constraints on exemplar models

The authors present 2 experiments that establish the presence of knowledge partitioning in perceptual categorization. Many participants learned to rely on a context cue, which did not predict category membership but identified partial boundaries, to gate independent partial categorization strategies. When participants partitioned their knowledge, a strategy used in 1 context was unaffected by knowledge demonstrably present in other contexts. An exemplar model, attentional learning covering map, was shown to be unable to accommodate knowledge partitioning. Instead, a mixture-of-experts model, attention to rules and instances in a unified model (ATRIUM), could handle the results. The success of ATRIUM resulted from its assumption that people memorize not only exemplars but also the way in which they are to be classified.     

Contingency awareness in a symptom learning paradigm: necessary but not sufficient?

In previous studies, we found that bodily symptoms can be learned in a differential conditioning paradigm, using odors as conditioned stimuli (CSs) and CO2-enriched air as unconditioned stimulus (US). However, this only occurred when the odor CS had a negative valence (a selective conditioning effect), and tended to be more pronounced in persons scoring high for Negative Affectivity (NA). This paper considers the necessity and/or sufficiency of awareness of the CS-US contingency in three studies using this paradigm. The relation between contingency awareness and the selective conditioning effect, and between contingency awareness and NA was also considered. Both self reported symptoms and respiratory physiology served as dependent variables. A learning effect on symptoms was found only for participants aware of the CS-US contingency, but not all participants reporting contingency awareness showed a learning effect. No conditioning effects appeared on the physiological measures. Also contingency awareness did not account for the selective conditioning effect, and did not interact with NA. Overall, the necessity but insufficiency hypotheses can only be withhold for group data and not for individual data.     

Functional neuroimaging studies of human emotions

Neuroimaging studies with positron emission tomography and functional magnetic resonance imaging have begun to describe the functional neuroanatomy of human emotion. Taken separately, specific studies vary in task dimensions and in type(s) of emotion studied, and are limited by statistical power and sensitivity. By examining findings across studies in a meta-analysis, we sought to determine if common or segregated patterns of activations exist in different emotions and across various emotional tasks. We surveyed over 55 positron emission tomography and functional magnetic resonance imaging activation studies, which investigated emotion in healthy subjects. This paper will review observations in several regions of interest in limbic (eg, amygdala, anterior cingulate cortex) and paralimbic (eg, medial prefrontal cortex, insula) brain regions in emotional responding.     

Do film cuts facilitate the perceptual and cognitive organization of activitiy sequences?

Film depictions of activities possess two kinds of structures--namely, the structural features of the depicted activities themselves and a formal structure defined by film cuts. The former structure is used by everyday observers for perceptually and cognitively unitizing the continuous flow of events into comprehensible entities. It seems conceivable that cuts can serve a similar unitizing purpose for film viewers. For each of two different activity sequences, two film versions were produced. Throughout each film version, cuts were placed either at breakpoints or at nonbreakpoints. In a 2 x 2 (activity sequence x film version) factorial design, 40 subjects segmented the film during viewing and recalled the film content after viewing in a detailed protocol. Segmentation behavior depended primarily on the occurrence of breakpoints and was largely unaffected by the occurrence of cuts. Cuts accompanying a breakpoint lead to more detailed recall protocols for these sections of the film.     

Dissimilar items benefit from phonological similarity in serial recall

In short-term serial recall, similar sounding items are remembered less well than items that do not sound alike. This phonological similarity effect has been observed with lists composed only of similar items, and also with lists that mix together similar and dissimilar items. An additional consistent finding has been what the authors call dissimilar immunity, the finding that ordered recall of dissimilar items is the same whether these items occur in pure dissimilar or mixed lists. The authors present 3 experiments that disconfirm these previous findings by showing that dissimilar items on mixed lists are recalled better than their counterparts on pure lists if order errors are considered separately from intrusion errors (Experiment 1), or if intrusion errors are experimentally controlled (Experiments 2 and 3). The memory benefit for dissimilar items on mixed lists poses a challenge for current models of short-term serial recall.     

Analysis of probabilistic classification learning in patients with Parkinson's disease before and after pallidotomy surgery

This study examined the characteristics of probabilistic classification learning, a form of implicit learning previously shown to be impaired in patients with basal ganglia dysfunction (e.g., Parkinson's disease). In this task, subjects learn to predict the weather using associations that are formed gradually across many trials, because of the probabilistic nature of the cue-outcome relationships. Patients with Parkinson's disease, both before and after pallidotomy, and age-matched control subjects, exhibited evidence of probabilistic classification learning across 100 training trials. However, pallidotomy appears to hinder the learning of associations most implicit in nature (i.e., weakly associated cues). Although subjects were most sensitive to single-cue associations when learning the task, there is evidence that cue combinations contribute significantly to probability learning. The utility of multiple dependent measures is discussed.     

The influence of the acoustic context on vertical sound localization in the median plane

The influence of background sounds (frames) on vertical localization of single sound sources (targets) was examined in four experiments. Loudspeakers (five targets and four frames) were positioned in the median plane, ranging from +30 degrees to -30 degrees above and below the subject's ear level. The subjects determined the vertical position of the targets by either verbal judgments or manual pointing. Frame and target sounds were presented concurrently or successively with a 1-sec interval; both consisted of (1) 300-Hz square waves, (2) noise, or (3) targets of noise and frames of 300-Hz square waves. Particularly in the second condition, the subjects consistently shifted the apparent target positions away from the frame locations. This contrast effect persisted even 1 sec after the offset of the frames. No effect was found with different waveforms for the frame and the target. Results are related to recent findings indicating a similar effect in the azimuthal dimension. Possibly the effect is based on a mechanism in which the auditory system adapts to recently heard sound source positions.     

Perception-action coupling during bimanual coordination: the role of visual perception in the coalition of constraints that govern bimanual action

Constraints pertaining to interlimb coordination have been studied extensively in the past decades. In this debate, F. Mechsner (2004) has taken a provocative position by putting primary emphasis on perceptual principles that mediate coordinative stability. Whereas the present authors agree that the role of perceptual principles is of critical importance during coordination, they take issue with Mechsner's extreme position and with the evidence forwarded to support a purely perceptual-cognitive approach to bimanual coordination. More specifically, the authors emphasize that current knowledge about brain function argues against a dualism between perception and action, criticize the presented evidence that posture manipulations during coordination provide decisive evidence against motoric and muscular constraints, and report on potential pitfalls associated with the use of visual transformation procedures to support complex coordination patterns.