Boskovic's unobservables

Boskovic treated unobservables in two different ways. During his earlier period (1741–48) the difference between observables and unobservables was a significant element of his specific semantic instrumentalism. The sentences of unobservables (such as absolute space, time and motions) were treated only as convenient tools conceived to provide for the empirical success of a theory. Later, especially in his Theory of Natural Philosophy (1763), Boskovic relativized this distinction by positing absolute properties (continuity and impenetrability), which are common to both observables and unobservables. As a scientific realist he was committed to his original unobservable entities, i.e. “points of matter”. Due to the intrinsic paradox contained in the concept of these points, his realist position was led to the absurd, which demands an anti‐realist interpretation of Boskovic's theory.     

Spatial compatibility of signal-response position in pointing

Two experiments are reported in which, by means of a pointing task, we studied the stimulus-position effect, i.e. the inverted U-shape form of the reaction-time function in relation to stimulus position in tasks in which stimuli and/or responses are arranged in a horizontal array. The response consisted of aiming the index finger from a central starting point at a target area on a screen. Reaction time was the main dependent variable. The spatial relation between the position of the imperative signal and the position of the response was manipulated by varying the spatial S-R compatibility and physical distance that separated the positions of stimulus and response. The stimulus-position effect was shown to depend on the compatibility of the S-R relation (Exp. 1). In Exp. 2 it was found that the modulation of the stimulus-position effect by spatial compatibility disappeared completely when the distance between the positions of stimulus and response was reduced. None of the experiments revealed that the stimulus position effect depended on signal discriminability, which renders an interpretation of this effect in terms of perceptual processes unlikely. We argue that the attentional model of spatial coding provides the most reasonable explanation of the obtained reaction-time patterns.     

Phenomenological approaches to personal identity

Phenomenology and the Cognitive Sciences - This special issue addresses the debate on personal identity from a phenomenological viewpoint, especially contemporary phenomenological research on...     

Association of serotonin transporter promoter gene polymorphism with violence: relation with personality disorders, impulsivity, and childhood ADHD psychopathology

There is evidence that disturbances in central serotonin (5-HT) function have a role in impulsive aggression, violence, and criminality. A deletion/insertion polymorphism within the 5-HT transporter (5-HTT) promoter gene (5-HTT gene-linked polymorphic region, 5-HTTLPR) is thought to be associated with several psychopathological phenotypes related to disturbed impulse control, anxiety and depression. This study examined the association of the 5-HTTLPR with violent behavior in a sample of 153 male Caucasians referred for a forensic psychiatric examination. We found a significant excess of the short (s) allele and the s/s genotype in patients characterized by recurrent and overt physical violent behavior. This genetic variance explained 5% of the variance of violent behavior. When controlled for the impact of several psychopathologies related to violent behavior, this association was observed in individuals with a history of childhood attention deficit/hyperactivity disorder (ADHD)-related symptoms, but not presenting with personality disorder or increased impulsiveness. In conclusion, the results (i). suggest an association between serotonergic dysfunction and violent behavior, (ii). provide evidence for an-at least partial-genetic regulation of violent behavior in a subgroup of male offenders, and (iii). suggest a significant role for 5-HT transporter functionality for violent behavior.     

The impact of semantic transparency of morphologically complex words on picture naming

We examined the contribution of semantic similarity to morphological priming effects, using the immediate (Exp. 1 and 3) and the delayed variant (Exp. 2) of picture-word interference. Distractor words were either compounds morphologically related to the picture name, but differing with respect to their semantic transparency (hummingbird, jailbird (Exp. 1); butterfly, butter dish (Exp. 3)), or form-related non-compound words (e.g., trombone). All three experiments revealed strong facilitation of picture naming due to morphologically related distractors. Form-related distractors facilitated picture naming in the immediate variant only, and to a lesser degree than compounds. Interestingly, the size of the morphemic effect was almost identical for semantically transparent and opaque complex words, which suggests that they share morphemic representations. These results suggest that morphological complexity in speech production is coded at the level of form representations, independent of semantic transparency.     

Countermanding saccades: evidence against independent processing of go and stop signals

In a stop signal paradigm, subjects were instructed to make a saccade to a visual target appearing left or right of the fixation point. In 25% of the trials, an auditory stop signal was presented after a variable delay that required the subject to inhibit the saccade. Observed saccadic response times in stop failure trials were longer than predicted by Logan and Cowan's (1984) race model. Saccadic response time and amplitude decreased with the time between stop signal presentation and saccade execution, suggesting an inhibitory effect between the stop signal and the go signal processes that is not compatible with an independent race assumption. Moreover, countermanding a saccade was more difficult when stop and go signals appeared at the same location.     

Use of self-reports of physical fitness as substitutes for performance-based measures of physical fitness in older adults

The purpose of the present study was to evaluate the association between self-reported physical fitness and performance-based measures of physical fitness in older adults. The specific components of physical fitness evaluated included aerobic endurance, muscular strength, and flexibility. Adults (25 men and 47 women) ranging in age from 56 to 92 years (M age=75 yr.) were recruited from the local community. Generally, the associations between self-reported and performance-based measures of physical fitness were low to moderate (r = 30-.01). Based on these findings, self-reports of physical fitness should not be used as substitutes for performance-based measures of physical fitness in older adults. Furthermore, present findings suggest that older adults, when asked to rate subcomponents of physical fitness, may not do so but rather evaluate a more general concept of physical fitness with aerobic endurance as the dominant factor.     

A Note on (K)Nots: Response to Robert W. Kentridge''s Commentary

GY, an extensively studied human hemianope, is aware of salient visual events in his cortically blind field but does not call this "vision." To learn whether he has low-level conscious visual sensations or whether instead he has gained conscious knowledge about, or access to, visual information that does not produce a conscious phenomenal sensation, we attempted to image process a stimulus s presented to the impaired field so that when the transformed stimulus T(s) was presented to the normal hemifield it would cause a sensation similar to that caused by s in the impaired field. While degradation of contrast, spatio-temporal filtering, contrast reversal, and addition of smear and random blobs all failed to match the response to a flashed bar s(f), moving textures of low contrast were accepted to match the response to a moving contrast-defined bar, s(m). Orientation and motion direction discrimination of the perceptually matched stimuli [s(m) and T(s(m))] was closely similar. We suggest that the existence of a satisfactory match indicates that GY has phenomenal vision.     

Empathic and non-empathic routes to visuospatial perspective-taking

The present study examined whether strategy moderated the relationship between visuospatial perspective-taking and empathy. Participants (N=96) undertook both a perspective-taking task requiring speeded spatial judgements made from the perspective of an observed figure and the Empathy Quotient questionnaire, a measure of trait empathy. Perspective-taking performance was found to be related to empathy in that more empathic individuals showed facilitated performance particularly for figures sharing their own spatial orientation. This relationship was restricted to participants that reported perspective-taking by mentally transforming their spatial orientation to align with that of the figure; it was absent in those adopting an alternative strategy of transposing left and right whenever confronted with a front-view figure. Our finding that strategy moderates the relationship between empathy and visuospatial perspective-taking enables a reconciliation of the apparently inconclusive findings of previous studies and provides evidence for functionally dissociable empathic and non-empathic routes to visuospatial perspective-taking.     

Parenting style in Spanish parents with children aged 6 to 14

The aim of this paper was to establish which parenting style of Spanish families is associated with optimum children's outcomes. A random Spanish sample of 1,103 parents of children and teenagers from 6 to 14 years of age, of whom 47% were females, reported on their child-rearing practices. Families were classified into 1 of 4 groups (authoritative, authoritarian, indulgent, or neglectful) based on the parents' answers. Socialization outcomes were 6 indicators of interpersonal relationship quality, 9 indicators of psychological adjustment, 7 indicators of personal competence, and 12 indicators of behavior problems. Results showed that indulgent and authoritative parenting styles were associated with better outcomes than authoritarian and neglectful parenting. Overall, our results supported the idea that, in Spain, the optimum parenting style is the indulgent one, as scores in the four sets of socialization outcomes among children and teenagers from indulgent families were always equal to, or even better than, the authoritative parenting style.