Long-term effects of prior cocaine exposure on Morris water maze performance

Cocaine addiction is associated with long-term cognitive alterations including deficits on tests of declarative/spatial learning and memory. To determine the extent to which cocaine exposure plays a causative role in these deficits, adult male Long-Evans rats were given daily injections of cocaine (30 mg/kg/day x 14 days) or saline vehicle. Three months later, rats were trained for 6 sessions on a Morris water maze protocol adapted from Gallagher, Burwell, and Burchinal [Gallagher, M., Burwell, R., & Burchinal, M. (1993). Severity of spatial learning impairment in aging: development of a learning index for performance in the Morris water maze. Behavioral Neuroscience, 107, 618-626]. Rats given prior cocaine exposure performed similarly to controls on training trials, but searched farther from the platform location on probe trials interpolated throughout the training sessions and showed increased thigmotaxis. The results demonstrate that a regimen of cocaine exposure can impair Morris water maze performance as long as 3 months after exposure. Although the impairments were not consistent with major deficits in spatial learning and memory, they may have resulted from cocaine-induced increases in stress responsiveness and/or anxiety. Increased stress and anxiety would be expected to increase thigmotaxis as well as cause impairments in searching for the platform location, possibly through actions on ventral striatal dopamine signaling.     

Not So Enticing Reasons

A common view of the relation between oughts and reasons is that you ought to do something if and only if that is what you have most reason to do. One challenge to this comes from what Jonathan Dancy calls ‘enticing reasons.’ Dancy argues that enticing reasons never contribute to oughts and that it is false that if the only reasons in play are enticing reasons then you ought to do what you have most reason to do. After explaining how enticing reasons supposedly work and why accepting them may appear attractive, I firstly show why we are not committed to accepting them into our conceptual framework and then argue that no reasons work in the way enticing reasons are claimed to. Thus we should reject the category of enticing reasons entirely.

Temporal Metaphysics in Z-Land

John Perry has argued that language, thought and experience often contain unarticulated constituents. I argue that this idea holds the key to explaining away the intuitive appeal of the A-theory of time and the endurance theory of persistence. The A-theory has seemed intuitively appealing because the nature of temporal experience makes it natural for us to use one-place predicates like past to deal with what are really two-place relations, one of whose constituents is unarticulated. The endurance view can be treated in a similar way; the temporal boundaries of temporal parts of objects are unarticulated in experience and this makes it seem that the very same entity exists at different times.     

REASONS AND MOTIVATION—NOT A WRONG DISTINCTION

This paper responds to Susan Hurley's attempt to undermine the adequacy of the distinction at the heart of the internalism-externalism debate about reasons for action. The paper shows that Hurley's argument fails and then, more positively, indicates a neat way to characterize the distinction.     

The roles of thought suppression and metacognitive beliefs in proneness to auditory verbal hallucinations in a non-clinical sample

In a non-clinical sample (N = 751), we investigated relations among two subscales (self-reported intrusiveness of unwanted thoughts and thought suppression) of the White Bear Suppression Inventory (WBSI), metacognitive beliefs, and proneness to auditory verbal hallucinations (AVHs). Both subscales of the WBSI were found to be related to AVH-proneness and strongly positively related to metacognitive beliefs about the uncontrollability and danger of thoughts. Regression analyses were used to test models of the relations among AVH-proneness and a range of metacognitive beliefs. When the WBSI subscale relating to the self-reported intrusiveness of unwanted thoughts was controlled for, the metacognitive style that was the strongest predictor of AVH-proneness was cognitive self-consciousness. Cognitive confidence and beliefs about the uncontrollability of thoughts were also significant predictors of AVH-proneness. These findings are used to revise existing models of the relations between metacognitive beliefs and AVHs. Implications for the management of AVHs are discussed.     

Socratic Questioning and Irony in Psychotherapeutic Practices

Journal of Contemporary Psychotherapy - Socratic questioning is employed in therapeutic interventions when the beliefs that clients express are critically evaluated using reason and logic. In this...     

Evolutionary Explanations of Indicatives and Imperatives

Recently there has been some interest in studying the explanation of meaning by using signaling games. I shall argue that the meaning of signals in signaling games remains sufficiently unclear to motivate further investigation. In particular, the possibility of distinguishing imperatives and indicatives at a fundamental level will be explored. Thereby I am trying to preserve the generality of the signaling games framework while bringing it closer to human languages. A number of convergence results for the evolutionary dynamics of our models will be proved.     

Cognitive-behaviour therapy for chronic fatigue syndrome: comparison of outcomes within and outside the confines of a randomised controlled trial

Outcomes for cognitive-behaviour therapy (CBT) in randomised controlled trials (RCTs) have rarely been compared to those in routine clinical practice. Taking the case of CBT for chronic fatigue syndrome (CFS), we evaluated the results of a successful RCT against those of the same treatment given in the same setting as part of routine practice. Fatigue and social adjustment scores were compared for patients who received CBT for CFS as part of a RCT (N=30) and patients who received CBT as part of everyday clinical practice (N=384). The results in the RCT were superior to those in routine clinical practice. Between pre-treatment and 6-month follow-up, the RCT showed a larger reduction in fatigue and greater improvement in social adjustment than those in routine treatment. The changes in fatigue scores were similar for both groups during treatment but were greater in the RCT between post-treatment and follow-up. Potential reasons for the superior results of the RCT include patient selection, therapist factors and the use of a manualised treatment protocol. Practitioners need to pay particular attention to relapse prevention and ensuring adequate follow-up in addition to encouraging patients to continue with cognitive-behavioural strategies once treatment has ended.     

The probability of causal conditionals

Conditionals in natural language are central to reasoning and decision making. A theoretical proposal called the Ramsey test implies the conditional probability hypothesis: that the subjective probability of a natural language conditional, P(if p then q), is the conditional subjective probability, P(q/p). We report three experiments on causal indicative conditionals and related counterfactuals that support this hypothesis. We measured the probabilities people assigned to truth table cases, P(pq), P(p notq), P( notpq) and P( notp notq). From these ratings, we computed three independent predictors, P(p), P(q/p) and P(q/ notp), that we then entered into a regression equation with judged P(if p then q) as the dependent variable. In line with the conditional probability hypothesis, P(q/p) was by far the strongest predictor in our experiments. This result is inconsistent with the claim that causal conditionals are the material conditionals of elementary logic. Instead, it supports the Ramsey test hypothesis, implying that common processes underlie the use of conditionals in reasoning and judgments of conditional probability in decision making.