Place learning in scopolamine-treated rats: the roles of distal cues and catecholaminergic mediation

Experiments 1 and 2 tested the hypothesis that cholinergic receptor antagonists impair place learning in a water maze by interfering with the processing of distal, visual cues. Extramaze cues were offered to rats in the form of geometrical patterns arranged on the inner circumference of a curtain surrounding the water maze. In Experiment 1 the animals were offered both the distal cues and proximal cues in the form of pingpong balls in fixed positions on the surface of the water while only distal cues were present in Experiment 2. Animals were injected with either scopolamine (0.5 mg/kg body wt) or saline 20 min prior to the daily place learning sessions. Upon reaching criterion level performance the animals were tested on "rotation" sessions on which the distal cues were displaced. The outcome of such "rotations" demonstrated that-regardless of the presence or absence of proximal cues-scopolamine-treated rats relied at least as much as normal animals on the distal cues. The acquisition phase of both Experiments 1 and 2 demonstrated an almost complete lack of scopolamine-associated impairment in acquisition and performance of the place learning task. In Experiment 3 (when scopolamine was no longer administered) the subjects of Experiment 2 were exposed to a series of pharmacological "challenges" of their place learning performance and eventually to surgical ablation of the anteromedial prefrontal cortex. The outcome of the pharmacological challenges and the postoperative test of task performance demonstrated that the place learning performance of animals which had acquired the task under scopolamine was mediated by a neural substrate dissimilar to the substrate of task performance in normal animals. Rats acquiring the task while deprived of the cholinergic system demonstrated above-normal contributions to task mediation from catecholaminergic-probably dopaminergic-mechanisms and tentative results pointed to a "shift" toward prefrontal task mediation.     

Religiosity and obsessive-compulsive behavior in Israeli Jews

Individual differences in obsessive-compulsive (OC) behavior in various cultures correlate with religiosity. The current paper explored the so far unstudied relationship between religiosity and OC behavior in Israeli Jews. Two studies were conducted. Study 1 focused on the relationship between religiosity and OC behavior in a representative sample of Israeli students. Study 2 focused on religious change and OC behavior in a non-random sample of 31 individuals who had become more religious (the MR group), and 30 individuals who were less religious (the LR group) than their parents. Instruments used were the Maudsley obsessive-compulsive inventory (MOCI), the student religiosity questionnaire, and questions about parental home observance, upbringing, and changes in religiosity. In the first study, no association was found between religiosity and OC behavior. Religiosity was related to some degree to perfectionism and to the parental attitude to upbringing. In the second study, a significant difference was observed between the MR and the LR groups on OC behavior as measured by the MOCI. Conclusion, among Israeli Jews a lot of religious observance is non-reflective, and is not associated with individual differences in personality or OC symptoms. Those who undergo religious change may do so in response to their behavioral propensities. One such path is that the more OC become MR, and the less OC less religiously observant.     

Visual analogue scale correlates of musculoskeletal fatigue

Visual analogue scale has been shown to reflect subjective feelings but rarely has it been used for musculoskeletal fatigue so in the present study VAS ratings were used to quantify musculoskeletal fatigue. A total of 20 students underwent a fatigue protocol (M age=21.3 yr., SD= 1.0). A series of randomized external loads at 0, 5, 10, 15, 25, 35, and 50% of the maximum voluntary contraction was generated by the BTE Primus and applied at the distal end of the dominant arm, which was sustained at the 90 degrees forward flexion position. After 60 sec. of force exertion for each loading, the subject marked the scale to reflect their extent of fatigue at the shoulder muscle. Analysis showed fatigue scores were significantly correlated with the percentages of maximum load applied (r =.73, p < or = .01). The correlation between higher external loads (25-50% maximum load) and fatigue scores was .57 (p < or = .01) and that for lower external loads (0-15% maximum load) was .44 (p < or = .01). The validity of using a visual analogue scale as a measure of musculoskeletal fatigue requires further study, particularly for a low load.     

Change in cognitive capabilities in the oldest old: the effects of proximity to death in genetically related individuals over a 6-year period

Change in cognitive abilities was assessed over a 6-year period in a sample of monozygotic and same-sex dizygotic twin pairs (N = 507 individuals), aged 80 and older (mean age = 83.3 years: SD = 3.1). who remained nondemented over the course of the study. Latent growth models (LGMs) show that chronological age and time to death are consistent predictors of decline in measures of memory, reasoning, speed, and verbal abilities. Multivariate LGM analysis resulted in weak and often negative correlations among rates of change between individuals within twin pairs, indicating greater differential change within twin pairs than occurs on average across twin pairs. These findings highlight several challenges for estimating genetic sources of variance in the context of compromised health and mortality-related change.     

Actor-observer differences in realism in confidence and frequency judgments

Taking a social psychological approach to metacognitive judgments, this study analyzed the difference in realism (validity) in confidence and frequency judgments (i.e., estimates of overall accuracy) between one's own and another person's answers to general knowledge questions. Experiment 1 showed that when judging their own answers, compared with another's answers, the participants exhibited higher overconfidence, better ability to discriminate correct from incorrect answers, lower accuracy, and lower confidence. However, the overconfidence effect could be attributable to the lowest level of confidence. Furthermore, when heeding additional information about another's answers the participants showed higher confidence and better discrimination ability. The overconfidence effect of Experiment 1 was not found in Experiment 2. However, the results of Experiment 2 were consistent with Experiment 1 in terms of discrimination ability, confidence, and accuracy. Finally, in both experiments the participants gave lower frequency judgments of their own overall accuracy compared with their frequency judgments of another person's overall accuracy.     

Ritualistic Behavior in Young Children

The aim of this study was to examine ritualistic behavior at its developmental peak. Children 20–59 months of age were sampled through a national system of daycare centers in Israel (N = 228). The order of onset of the ritual behaviors measured was virtually identical to that reported for an American sample (D. W. Evans et al., 1997). Gender and age effects were found for fearfulness but not for ritualistic behavior. Maternal reports of ritualistic behavior were highly correlated with reported fears, and with shy and emotional temperament. Mothers of the children who were in the top 10% in their use of rituals according to maternal report, worried about their child's ritualistic behavior, even though maternal worry was not correlated with ritualistic behavior for the whole distribution.     

Effects of facial expression on working memory

In long‐term memory (LTM) emotional content may both enhance and impair memory, however, disagreement remains whether emotional content exerts different effects on the ability to maintain and manipulate information over short intervals. Using a working‐memory (WM) recognition task requiring the monitoring of faces displaying facial expressions of emotion, participants judged each face as identical (target) or not (non‐target) to that presented 2 trials back (2‐back). Negative expression was better and faster recognised, illustrated by higher target discriminability and target detection. Positive and negative expressions also induced a more liberal detection bias compared with neutral. Taking the preceding item into account, additional accuracy impairment (negative preceding negative target) and enhancement effects (negative or positive preceding neutral target) appeared. This illustrates a differential modulation of WM based on the affective tone of the target (mirroring LTM enhancement‐ and recognition bias effects), and of the preceding item (enhanced and impaired target detection).     

Reading times and adaptive styles among patients diagnosed with psychosis as assessed by the Serial Color-Word Test

The present study focuses on how patients diagnosed with psychosis deal with a conflicting situation. In the study, two groups of patients were assessed. One group consisted of patients diagnosed with psychosis (n = 41), while the comparison group (n = 135) consisted of inpatients diagnosed either with anorexia nervosa or with bulimia nervosa. The groups were assessed using the Serial Color Word Test (S-CWT), designed for studying an individual's successive adaptation over time to a conflicting situation. The S-CWT differentiated the two groups regarding both reading time and adaptive styles. Patients diagnosed with psychosis had longer reading times and an adaptive style that was deviant throughout the test, indicating poorer cognitive functioning and more serious psychopathology. These problems may in turn influence functioning in work or study and daily living, all of which are important in treatment planning.     

Individual differences in 10‐month‐olds' performance on the A‐not‐B task

This study used the classical A‐not‐B task (Piaget, 1954 ) to explore individual differences in cognitive flexibility in 10‐month‐old infants by: (1) examining how differences in search performance during A trials relate to search performance during B trials; (2) studying the relation between temperamental dimensions and A‐not‐B performance; and (3) investigating differences in search performance between looking and reaching responses within the same task. Forty infants were tested on a fixed‐design‐version of the A‐not‐B task, not allowing for training or individual adjustment, but instead eliciting additional search behaviors than the common correct responses in A trials and perseverative errors in B trials. Infants were also rated by their parents on the temperamental scales Activity level and Attention span. The main findings were: (1) performance on A trials affected B trial performance, with infants being more correct on A trials having more incorrect and less ‘no search’ responses on B trials; (2) activity level, but not attention span, was related to performance on the A‐not‐B task, with infants performing better on A trials having a lower activity level; and (3) there were a few differences in performance with regard to modality, indicating that responding correctly by looking may be less cognitively demanding than doing so by reaching. This study demonstrated that 10‐month‐olds show a wide variation of search behaviors on this A‐not‐B task, resulting in individual differences in performance. These differences are suggested to reflect variation in temperamental activity level as well as maturity of short term/working memory, inhibition and cognitive flexibility.     

It depends on how you look at it: Scanpath comparison in multiple dimensions with MultiMatch, a vector-based approach

Eye movement sequences??or scanpaths??vary depending on the stimulus characteristics and the task (Foulsham & Underwood Journal of Vision, 8(2), 6:1?C17, 2008; Land, Mennie, & Rusted, Perception, 28, 1311?C1328, 1999). Common methods for comparing scanpaths, however, are limited in their ability to capture both the spatial and temporal properties of which a scanpath consists. Here, we validated a new method for scanpath comparison based on geometric vectors, which compares scanpaths over multiple dimensions while retaining positional and sequential information (Jarodzka, Holmqvist, & Nystr?m, Symposium on Eye-Tracking Research and Applications (pp. 211?C218), 2010). ??MultiMatch?? was tested in two experiments and pitted against ScanMatch (Cristino, Math?t, Theeuwes, & Gilchrist, Behavior Research Methods, 42, 692?C700, 2010), the most comprehensive adaptation of the popular Levenshtein method. In Experiment 1, we used synthetic data, demonstrating the greater sensitivity of MultiMatch to variations in spatial position. In Experiment 2, real eye movement recordings were taken from participants viewing sequences of dots, designed to elicit scanpath pairs with commonalities known to be problematic for algorithms (e.g., when one scanpath is shifted in locus or when fixations fall on either side of an AOI boundary). The results illustrate the advantages of a multidimensional approach, revealing how two scanpaths differ. For instance, if one scanpath is the reverse copy of another, the difference is in the direction but not the positions of fixations; or if a scanpath is scaled down, the difference is in the length of the saccadic vectors but not in the overall shape. As well as having enormous potential for any task in which consistency in eye movements is important (e.g., learning), MultiMatch is particularly relevant for ??eye movements to nothing?? in mental imagery and embodiment-of-cognition research, where satisfactory scanpath comparison algorithms are lacking.