Knowledge and abilities: The need for a new understanding of knowing-how

Stanley and Williamson (The Journal of Philosophy 98(8), 411–444 2001) reject the fundamental distinction between what Ryle once called ‘knowing-how’ and ‘knowing-that’. They claim that knowledge-how is just a species of knowledge-that, i.e. propositional knowledge, and try to establish their claim relying on the standard semantic analysis of ‘knowing-how’ sentences. We will undermine their strategy by arguing that ‘knowing-how’ phrases are under-determined such that there is not only one semantic analysis and by critically discussing and refuting the positive account of knowing-how they offer. Furthermore, we argue for an extension of the classical ‘knowing-how’/‘knowing-that’-dichotomy by presenting a new threefold framework: Using some core-examples of the recent debate, we will show that we can analyze knowledge situations that are not captured by the Rylean dichotomy and argue that, therefore, the latter has to be displaced by a more fine-grained theory of knowledge-formats. We will distinguish three different formats of knowledge we can have of our actions, namely (1) propositional, (2) practical, and (3) image-like formats of knowledge. Furthermore, we will briefly analyze the underlying representations of each of these knowledge-formats.     

The development of hazard perception: Dissociation of visual orientation and hazard processing

Eye movements are a key behavior for visual information processing in traffic situations and for vehicle control. Previous research showed that effective ways of eye guidance are related to better hazard perception skills. Furthermore, hazard perception is reported to be faster for experienced drivers as compared to novice drivers. However, little is known whether this difference can be attributed to the development of visual orientation, or hazard processing. In the present study, we compared eye movements of 20 inexperienced and 20 experienced drivers in a hazard perception task. We separately measured (a) the interval between the onset of a static hazard scene and the first fixation on a potential hazard, and (b) the interval between the first fixation on a potential hazard and the final response. While overall RT was faster for experienced compared to inexperienced drivers, the scanning patterns revealed that this difference was due to faster processing after the initial fixation on the hazard, whereas scene scanning times until the initial fixation on the hazard did not differ between groups.     

Practice Effects in Bimanual Force Control: Does Age Matter?

ABSTRACT

The authors examined age-related differences in fine motor control during a bimanual coordination task. The task required the modulation of fingertip forces in the precision grip according to a visually presented sinusoidal antiphase pattern (force range 2–12 N; frequency 0.2 Hz). Thirty-four right-handed participants of three age groups (young, early middle-aged, and late middle-aged) practiced 30 trials of the task. Accuracy and variability of relative timing and relative forces at minima and maxima of the sine wave were analyzed for hand–hand and hand–stimulus couplings and compared between age groups. Analysis showed for relative timing and force weaker hand–hand than hand–stimulus coupling as well as lower accuracy and higher variability for minima as compared to maxima. Further, we analyzed practice effects by comparing the first and last trials and characterized the course of practice by detecting the transition of a steeper to a shallower acquisition slope for the different age groups. Late middle-aged participants demonstrated poorer performance than both other groups for all parameters. All groups improved performance to a similar amount. However, an age-related difference in acquisition strategy is visible. Late middle-aged participants seemed to have focused on improvement of force amplitude, whereas young and early middle-aged focused on timing.     

When the going gets tough…: Self-motivation is associated with invigoration and fun

Personality systems interaction (PSI) theory postulates two executive control modes in volitional action: Self-control and self-regulation (self-motivation). Self-control should deplete energy whereas self-motivation should maintain energy and result in invigoration. There were three groups of participants: Self-control, self-motivation, and pretend, who performed a resource-demanding Stroop-Shift and an anagram task. Performance and energy expenditure were examined in each task. Compared to the other groups, the self-motivation group showed increments in blood glucose throughout the experiment, indicating invigoration, and had better performance on the difficult Stroop-Shift task than the self-control group. Additionally, for the self-motivation group anagram performance correlated with less effort and ease of concentration and was moderated by fun in the task. These results are consonant with the predictions of PSI and self-determination theories. It is concluded that self-control depletes resources whereas self-motivation is associated with invigoration in carrying resource-demanding tasks.     

Age-related slowing in face and name recognition: evidence from event-related brain potentials

Age-related slowing in recognizing famous names and faces was investigated with event-related brain potentials (ERPs). In a group of young adults, item repetition induced early (220-340 ms) and late (400-700 ms) ERP modulations, apparently signaling the access to, respectively, domain-specific representations of faces and names and domain-general semantic knowledge about the persons. These repetition effects and other ERP components were then used as process-specific time markers in middle-aged and elderly participants. For both faces and names, the elderly participants' responses were slowed, but repetition priming in reaction times was not. The ERP latencies suggested that most of the age-related slowing occurred in the access to domain-specific representations and during response decision, whereas sensory and perceptual processing was largely spared.     

Perspectives of children and adolescents on the perceived determinants of physical activity during recess

Promotion of healthy lifestyles in youth focuses on school-based interventions with the aim to increase physical activity (PA) during school days. Drawing on seventeen focus group discussions from three purposively selected Estonian schools, we explored factors that perceivably affect students’ recess physical activity (RPA). Both inductive and deductive principles of data analysis were used to extract major and subthemes related to factors that inhibit or enhance RPA. Participants identified barriers and facilitators to recess PA as originating mainly from physical and organizational school environment. Also, unsuitable weather was described as a barrier to being active. Additionally, feelings, behavioral and normative beliefs were described as constraining or facilitating RPA. Results highlighted two culture-specific unique perceived determinants of RPA that need to be addressed during the development of school-based interventions to increase PA.