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Seeing yourself through others' eyes: A study of spontaneously occurring images in social phobia
A recent cognitive model of social phobia suggested that negative self-images may play an important role in maintaining the disorder. To investigate this suggestion, 30 social phobics and 30 non-patient controls were given a semi-structured interview which focused on spontaneously occurring images. Social phobics were significantly more likely than controls to report experiencing images when anxious in social situations. In addition, social phobics' images were significantly more negative and significantly more likely to involve seeing oneself from an observer's perspective. Implications of these findings for the understanding and cognitive treatment of social phobia are discussed.
How do I look with my minds eye: perspective taking in social phobic imagery.
This study explored perspective taking in social phobics' images of past anxiety-provoking social situations and non-social situations. For images of social situations, social phobics were significantly more likely than non-patient controls to take an observer perspective, viewing themselves as if from an external point of view. In contrast, social phobics and controls did not differ in the perspective taken in images of non-social situations, which were generally viewed from a field perspective (seeing the situation as if looking out through their own eyes). The clinical significance of these findings is briefly discussed.
Grounding predictive coding models in empirical neuroscience research.
Clark makes a convincing case for the merits of conceptualizing brains as hierarchical prediction machines. This perspective has the potential to provide an elegant and powerful general theory of brain function, but it will ultimately stand or fall with evidence from basic neuroscience research. Here, we characterize the status quo of that evidence and highlight important avenues for future investigations.
Ablating adult neurogenesis in the rat has no effect on spatial processing: evidence from a novel pharmacogenetic model.
The function of adult neurogenesis in the rodent brain remains unclear. Ablation of adult born neurons has yielded conflicting results about emotional and cognitive impairments. One hypothesis is that adult neurogenesis in the hippocampus enables spatial pattern separation, allowing animals to distinguish between similar stimuli. We investigated whether spatial pattern separation and other putative hippocampal functions of adult neurogenesis were altered in a novel genetic model of neurogenesis ablation in the rat. In rats engineered to express thymidine kinase (TK) from a promoter of the rat glial fibrillary acidic protein (GFAP), ganciclovir treatment reduced new neurons by 98%. GFAP-TK rats showed no significant difference from controls in spatial pattern separation on the radial maze, spatial learning in the water maze, contextual or cued fear conditioning. Meta-analysis of all published studies found no significant effects for ablation of adult neurogenesis on spatial memory, cue conditioning or ethological measures of anxiety. An effect on contextual freezing was significant at a threshold of 5% (P = 0.04), but not at a threshold corrected for multiple testing. The meta-analysis revealed remarkably high levels of heterogeneity among studies of hippocampal function. The source of this heterogeneity remains unclear and poses a challenge for studies of the function of adult neurogenesis.
It's not just what we encode, but how we encode it: associations between neuroticism and learning.
OBJECTIVE: Neuroticism is a strong predictor of future mental health problems. The informativeness of this association has been questioned because of the limited understanding of the mechanisms underlying Neuroticism. In this article the authors extend our understanding of the association between information processing and Neuroticism. METHOD: Two independent studies involving separate sets of college students (N = 89 and N = 33), use self-rated Neuroticism scores to compare individuals' ability to learn simple and more complex discriminations, between simple shapes and words presented alone and in compound. RESULTS: Neuroticism was found to be associated with differences in learning to discriminate simple stimuli from compounds containing the same simple stimuli. Individuals with high levels of Neuroticism appeared to process compounds of stimuli as whole units even when this ceased to be an effective strategy for learning. In contrast, individuals with lower levels of Neuroticism performed better with discriminations that could be solved while learning about separate stimuli, rather than compounds. CONCLUSIONS: The authors discuss possible mechanisms of learning identified by these tasks and consider what implications their observations have for an understanding of the relationship between Neuroticism and mental health problems.
Dysphoric mood states are related to sensitivity to temporal changes in contingency
A controversial finding in the field of causal learning is that mood contributes to the accuracy of perceptions of uncorrelated relationships. When asked to report the degree of control between an action and its outcome, people with dysphoria or depression are claimed to be more realistic in reporting non-contingency (e.g., Alloy and Abramson, 1979). The strongest evidence for this depressive realism (DR) effect is derived from data collected with experimental procedures in which the dependent variables are verbal or written ratings of contingency or cause, and, perhaps more importantly, the independent variable in these procedures may be ambiguous and difficult to define. In order to address these possible confounds, we used a two-response free-operant causal learning task in which the dependent measures were performance based. Participants were required to respond to maximize the occurrence of a temporally contiguous outcome that was programmed with different probabilities, which also varied temporally across two responses. Dysphoric participants were more sensitive to the changing outcome contingencies than controls even though they responded at a similar rate. During probe trials, in which the outcome was masked, their performance recovered more quickly than that of the control group. These data provide unexpected support for the DR hypothesis suggesting that dysphoria is associated with heightened sensitivity to temporal shifts in contingency. © 2012 Msetfi, Murphyand Kornbrot.
Rats do learn XYX rules
The critical review of the rats learning pattern XYX and its transfer to novel stimuli is presented. Corballis claims that human infants and cotton top tamarins, if confronted with the same kind of task, may have used a subset of stimuli to solve the rule discrimination. Rats learning that XYX was the reinforced sequence may have matched the identity of the first and last stimulus (X), ignoring the interposed element (Y), and that this would be sufficient to discriminate XYX from YYX or YXX. Rats in each of the three groups were behaving on the basis of different learning strategies. Corballis challenges the lack of a statistical difference by way of a hypothesized floor effect. Configurable pattern-learning strategies are also ineffective in solving the discrimination. Mammals like rats can acquire rules that imply at least some level of abstraction and are considered to be involved in language learning have implications for any debate on the evolution of language and should be in accordance with an evolutionary perspective of cognition.
The effect of mild depression on time discrimination.
Depressed mood states affect subjective perceptions of time but it is not clear whether this is due to changes in the underlying timing mechanisms, such as the speed of the internal clock. In order to study depression effects on time perception, two experiments using time discrimination methods with short (<300 ms) and long (>1,000 ms) durations were conducted. Student participants who were categorized as mildly depressed by their scores on the Beck Depression Inventory were less able than controls to discriminate between two longer durations but were equally able to discriminate shorter intervals. The results suggest that mildly depressed or dysphoric moods do not affect pacemaker speed. It is more likely that depression affects the ability to maintain attention to elapsing duration.
Context and time in causal learning: contingency and mood dependent effects.
Defining cues for instrumental causality are the temporal, spatial and contingency relationships between actions and their effects. In this study, we carried out a series of causal learning experiments that systematically manipulated time and context in positive and negative contingency conditions. In addition, we tested participants categorized as non-dysphoric and mildly dysphoric because depressed mood has been shown to affect the processing of all these causal cues. Findings showed that causal judgements made by non-dysphoric participants were contextualized at baseline and were affected by the temporal spacing of actions and effects only with generative, but not preventative, contingency relationships. Participants categorized as dysphoric made less contextualized causal ratings at baseline but were more sensitive than others to temporal manipulations across the contingencies. These effects were consistent with depression affecting causal learning through the effects of slowed time experience on accrued exposure to the context in which causal events took place. Taken together, these findings are consistent with associative approaches to causal judgement.
Maybe this old dinosaur isn't extinct: What does Bayesian modeling add to associationism?
We agree with Jones & Love (J&L) that much of Bayesian modeling has taken a fundamentalist approach to cognition; but we do not believe in the potential of Bayesianism to provide insights into psychological processes. We discuss the advantages of associative explanations over Bayesian approaches to causal induction, and argue that Bayesian models have added little to our understanding of human causal reasoning. © 2011 Cambridge University Press.
A role for CS-US contingency in Pavlovian conditioning.
Two experiments evaluated the role of conditioned stimulus-unconditioned stimulus (CS-US) contingency in appetitive Pavlovian conditioning in rats. In both experiments, some groups received a positively contingent CS signaling an increased likelihood of the US relative to the absence of the CS. These groups were compared with control treatments in which the likelihood of the US was the same in the presence and absence of the CS. A trial marker served as a trial context. Experiment 1 found contingency sensitivity. There was a reciprocal relationship between responding to the CS and the trial marker. Experiment 2 showed that this result was not stimulus or response specific. These results are consistent with associative explanations and the idea that rats are sensitive to CS-US contingency.
Contiguity and the outcome density bias in action-outcome contingency judgements.
In cause-outcome contingency judgement tasks, judgements often reflect the actual contingency but are also influenced by the overall probability of the outcome, P(O). Action-outcome instrumental learning tasks can foster a pattern in which judgements of positive contingencies become less positive as P(O) increases. Variable contiguity between the action and the outcome may produce this bias. Experiment 1 recorded judgements of positive contingencies that were largely uninfluenced by P(O) using an immediate contiguity procedure. Experiment 2 directly compared variable versus constant contiguity. The predicted interaction between contiguity and P(O) was observed for positive contingencies. These results stress the sensitivity of the causal learning mechanism to temporal contiguity.
Depressive realism and the effect of intertrial interval on judgements of zero, positive, and negative contingencies.
In three experiments we tested how the spacing of trials during acquisition of zero, positive, and negative response-outcome contingencies differentially affected depressed and nondepressed students' judgements. Experiment 1 found that nondepressed participants' judgements of zero contingencies increased with longer intertrial intervals (ITIs) but not simply longer procedure durations. Depressed groups' judgements were not sensitive to either manipulation, producing an effect known as depressive realism only with long ITIs. Experiments 2 and 3 tested predictions of Cheng's (1997) Power PC theory and the Rescorla-Wagner (1972) model, that the increase in context exposure experienced during the ITI might influence judgements most with negative contingencies and least with positive contingencies. Results suggested that depressed people were less sensitive to differences in contingency and contextual exposure. We propose that a context-processing difference between depressed and nondepressed people removes any objective notion of "realism" that was originally employed to explain the depressive realism effect (Alloy & Abramson, 1979).
5-HT modulation by acute tryptophan depletion of human instrumental contingency judgements.
INTRODUCTION: The concept of 'depressive realism', that depression leads to more accurate perception of causal control, has been influential in the field of depression research, but remains controversial. Recent work testing contingency learning has suggested that contextual processing might determine realism-like effects. Serotonin (5-hydroxytryptamine, (5-HT)), which is implicated in the pathophysiology of depression, might also influence contextual processing. Using acute tryptophan depletion (ATD), we tested the hypothesis that dysfunctional serotoninergic neurotransmission influences contingency judgements in dysphoric subjects via an effect on contextual processing. MATERIALS AND METHODS: We employed a novel contingency learning task to obtain separate measures (ratings) of the causal effect of participants' responses and efficacy of the background context over an outcome. Participants, without a history of depression, completed this task on and off ATD in a double-blind, placebo-controlled, within-subjects design. RESULTS: As with other work on contingency learning, the effects of ATD were related to baseline mood levels. Although no overall effects of ATD were observed, the subgroup of participants with low Beck depression inventory (BDI) scores showed reduced ratings of contextual control and improved accuracy of contingency judgements under positive contingencies following ATD, compared to placebo. High BDI participants demonstrated low accuracy in contingency judgements, regardless of serotoninergic status. CONCLUSIONS: No effect of ATD on contingency judgements was observed in the group as a whole, but effects were observed in a subgroup of participants with low BDI scores. We discuss these data in light of the context processing hypothesis, and prior research on 5-HT and depressive realism.
Stereotype formation: biased by association.
We propose that biases in attitude and stereotype formation might arise as a result of learned differences in the extent to which social groups have previously been predictive of behavioral or physical properties. Experiments 1 and 2 demonstrate that differences in the experienced predictiveness of groups with respect to evaluatively neutral information influence the extent to which participants later form attitudes and stereotypes about those groups. In contrast, Experiment 3 shows no influence of predictiveness when using a procedure designed to emphasize the use of higher level reasoning processes, a finding consistent with the idea that the root of the predictiveness bias is not in reasoning. Experiments 4 and 5 demonstrate that the predictiveness bias in formation of group beliefs does not depend on participants making global evaluations of groups. These results are discussed in relation to the associative mechanisms proposed by Mackintosh (1975) to explain similar phenomena in animal conditioning and associative learning.
Learned irrelevance and retrospective correlation learning.
In 1973 Mackintosh reported an interference effect that he called learned irrelevance in which exposure to uncorrelated (CS/US) presentation of the unconditional stimulus (US) and the conditioned stimulus (CS) interfered with future Pavlovian conditioning. It has been argued that there is no specific interference effect in learned irrelevance; rather the interference is the sum of independent CS and US exposure effects (CS + US). We review previous research on this question and report two new experiments. We conclude that learned irrelevance is a consequence of a contingency learning and a specific learned irrelevance mechanism. Moreover even the independent exposure controls, used in previous experiments to support the CS and US exposure account, provide support for the correlation learning process.