The philosophical–anthropological foundations of Bennett and Hacker’s critique of neuroscience

Bennett and Hacker criticize a number of neuroscientists and philosophers for attributing capacities which belong to the human being as a whole, like perceiving or deciding, to a “part” of the human being, viz. the brain. They call this type of mistake the “mereological fallacy”. Interestingly, the authors say that these capacities cannot be ascribed to the mind either. They reject not only materialistic monism but also Cartesian dualism, arguing that many predicates describing human life do not refer to physical or mental properties, nor to the sum of such properties. I agree with this important principle and with the critique of the mereological fallacy which it underpins, but I have two objections to the authors’ view. Firstly, I think that the brain is not literally a part of the human being, as suggested. Secondly, Bennett and Hacker do not offer an account of body and mind which explains in a systematic way how the domain of phenomena which transcends the mental and the physical relates to the mental and the physical. I first argue that Helmuth Plessner’s philosophical anthropology provides the kind of account we need. Then, drawing on Plessner, I present an alternative view of the mereological relationships between brain and human being. My criticism does not undercut Bennett and Hacker’s diagnosis of the mereological fallacy but rather gives it a more solid philosophical–anthropological foundation.     

Object files across eye movements: Previous fixations affect the latencies of corrective saccades

One of the factors contributing to a seamless visual experience is object correspondence—that is, the integration of pre- and postsaccadic visual object information into one representation. Previous research had suggested that before the execution of a saccade, a target object is loaded into visual working memory and subsequently is used to locate the target object after the saccade. Until now, studies on object correspondence have not taken previous fixations into account. In the present study, we investigated the influence of previously fixated information on object correspondence. To this end, we adapted a gaze correction paradigm in which a saccade was executed toward either a previously fixated or a novel target. During the saccade, the stimuli were displaced such that the participant’s gaze landed between the target stimulus and a distractor. Participants then executed a corrective saccade to the target. The results indicated that these corrective saccades had lower latencies toward previously fixated than toward nonfixated targets, indicating object-specific facilitation. In two follow-up experiments, we showed that presaccadic spatial and object (surface feature) information can contribute separately to the execution of a corrective saccade, as well as in conjunction. Whereas the execution of a corrective saccade to a previously fixated target object at a previously fixated location is slowed down (i.e., inhibition of return), corrective saccades toward either a previously fixated target object or a previously fixated location are facilitated. We concluded that corrective saccades are executed on the basis of object files rather than of unintegrated feature information.     

The efficacy of cognitive-behavioral interventions for reducing anxiety sensitivity: a meta-analytic review

The present study meta-analytically reviewed the efficacy of cognitive-behavioral therapy (CBT) vs. control conditions in the reduction of anxiety sensitivity. A computerized search was conducted to indentify CBT outcome studies that included the Anxiety Sensitivity Index as a dependent variable. Of the 989 studies that were identified, 24 randomized-controlled trials with a total of 1851 participants met inclusion criteria and were included in the analysis. Data were extracted separately for treatment-seeking (16 studies) and at-risk (eight studies) samples. Results indicated large effect sizes for treatment-seeking samples, Hedges' g=1.40, SE=0.21, 95% CI: 1.00-1.81, p<0.001, and moderate to large effect sizes for at risk samples Hedges' g=0.74, SE=0.18, 95% CI: 0.39-1.08, p<0.001. Additionally, both the amount of therapist contact and control modality (waitlist vs. psychological control) moderated the effect sizes for treatment-seeking samples. Our review indicates that CBT is efficacious in reducing anxiety sensitivity. However, more research is needed to determine the mechanisms by which CBT exert its effects on anxiety sensitivity.     

Indirect object recognition: evidence for associative processes in recognition memory

Rats' exploration of stimulus P (e.g., a domestic object) is reduced following either its direct exposure or its indirect exposure and is taken to indicate recognition memory. Procedures for demonstrating indirect object recognition involve an initial presentation of object P with stimulus X (and of an object Q with stimulus Y). On test, stimulus X is presented with objects P and Q and rats' exploration of Q exceeds their exploration of P. One interpretation here is that the presentation of stimulus X on test associatively activates the memory of object P, which diminishes exploration of P relative to Q. It is possible, instead, that performance is simply the result of a novel pattern of stimulation generated by the unfamiliar combination of X and Q. The authors modified this procedure to reduce the likelihood of such a process. Their procedure involved first the presentation of PX and QY before the presentation of stimulus X alone. During the test that followed, objects P and Q were presented but stimulus X was removed. The authors found that exploration of Q remained greater than that of P despite these modifications and discuss some theoretical implications of indirect, associative processes in recognition memory.     

Interhemispheric interaction and egocentrism: the role of handedness in social comparative judgement

Previous research has shown that people are egocentrically biased when making judgements that require a self-to-peer comparison - leading to above-/below-average effects and comparative optimism/pessimism. Two experiments examined whether interhemispheric brain connectivity (assessed via strength of handedness) is associated with egocentrism in the comparative judgement process. In Experiment 1, strong handers (SH) and mixed handers (MH) made percentile rank judgements about their abilities in easy and hard domains. In Experiment 2, SH and MH judged their likelihoods of outperforming a co-participant in easy and hard tasks. Both experiments showed that SH were more egocentric than MH and thus showed (a) more above- and below-average effects when estimating their abilities (Experiment 1) and (b) generally larger optimism biases when predicting performances in a competition (Experiment 2). Taken together, these experiments provide evidence that underlying interhemispheric connectivity shapes egocentrism in comparative judgement.