Response coding and visuomotor transformation in the Simon task: the role of action goals

Manual responses can be defined by differing response parameters. Any of them may generate a Simon effect. For all those response parameters, the same implementation of the Simon effect (in terms of subserving mechanism) is assumed. In 3 experiments, subjects had to respond with either fingers or sticks. Temporal properties of the Simon effect changed with response parameters relevant in a task. The Simon effect for manual responses decayed. For stick responses, in which the action goal differed from the anatomical mapping of the acting hand, a sustained Simon effect was observed. However, if the action goal for stick responses was not instrumental for selecting the correct response, the Simon effect decayed. The findings are consistent with the notion of different mechanisms involved in generating a Simon effect.     

Perceptual and attentional factors in encoding irrelevant spatial information

Numerous studies found superior performance when the irrelevant location of a stimulus and response location were corresponding than when they were not corresponding (Simon effect), suggesting that stimulus location is processed in an obligatory manner. The present study compared Simon effects from the location of a relevant (i.e., to-be-attended) object to those from the location of an irrelevant (i.e., to-be-ignored) object. In four experiments, participants were presented with a rectangular frame and a square, with the relevant object in green or red color and the irrelevant object in gray or white color. Participants’ task was to respond with a lateral keypress to the color of the relevant object, and we varied spatial correspondence between the location of the relevant or the irrelevant object and the response, respectively. Results consistently showed larger Simon effects from the location of the relevant than from the irrelevant object, even when the irrelevant object was made very salient. These results suggest that location processing is largely confined to relevant (i.e., attended) objects, stressing the role of attention shifts for location encoding.     

Split-Brain: What We Know Now and Why This is Important for Understanding Consciousness

Neuropsychology Review - Recently, the discussion regarding the consequences of cutting the corpus callosum (“split-brain”) has regained momentum (Corballis, Corballis, Berlucchi,...     

Age and physiological, perceptual, and affective responses during walking at a self-selected pace

The aim of this study was to examine physiological, perceptual, and affective responses during self-paced walking for three age groups. 66 adult women were assigned into three groups by age: 20-25 yr. (n=22), 30-35 yr. (n=22), and 40-45 yr. (n=22). Each participant completed a maximal exercise test and a 20-min. bout of walking at a self-selected pace. The preferred walking speed was similar for all age groups, whereas physiological responses relative to maximal and ventilatory threshold values were greater in the 40-45 yr. group than the other two groups. Nevertheless, perceptual and affective responses were similar for all age groups. These findings suggest that physiological responses, but not perceptual and affective responses, of sedentary women are associated with age during walking at a self-selected pace.     

The Influence of Einstein on Wittgenstein's Philosophy

On the basis of historical and textual evidence, this paper claims that (i) after his Tractatus, Wittgenstein was actually influenced by Einstein's theory of relativity and, (ii) the similarity of Einstein's relativity theory helps to illuminate some aspects of Wittgenstein's work. These claims find support in remarkable quotations where Wittgenstein speaks approvingly of Einstein's relativity theory and in the way these quotations are embedded in Wittgenstein's texts. The profound connection between Wittgenstein and relativity theory concerns not only Wittgenstein's “verificationist” phase (more closely connected with Schlick's work), but also Wittgenstein's later philosophy centred on the theme of rule‐following.     

Attentional distractor interference may be diminished by concurrent working memory load in normal participants and traumatic brain injury patients

A reduction in congruency effects under working memory (WM) load has been previously described using different attentional paradigms (e.g.,  and ). One hypothesis is that different types of WM load have different effects on attentional selection, depending on whether a specific memory load demands resources in common with target or distractor processing. In particular, if information in WM is related to the distractors in the selective attention task, there is a reduction in distraction (Kim et al., 2005). However, although previous results seem to point to a decrease in interference under high WM load conditions (Kim et al., 2005), the lack of a neutral baseline for the congruency effects makes it difficult to differentiate between a decrease in interference or in facilitation. In the present work we included neutral trials in the task introduced by Kim et al. (2005) and tested normal participants and traumatic brain injury patients. Results support a reduction in the processing of distractors under WM load, at least for incongruent trials in both groups. Theoretical as well as applied implications are discussed.