Developing algorithms to enhance the sensitivity of cancellation tests of visuospatial neglect

We describe a set of algorithms that enhance the sensitivity of cancellation tests used in assessing visuospatial neglect. The algorithms can be readily implemented on a computer and can provide temporal and nontemporal data on strategies used during cancellation. We also present preliminary results from a group of 68 right-hemisphere brain-damaged patients and 12 age-matched control participants, which demonstrate the clinical significance of the measures we have defined.     

Intense classification training to increase the detection of drowning swimmers

Lifeguards engage in a continuous process of deciding whether swimmers are in danger or not. The variety of behaviours that distressed swimmers show makes it difficult to impart declarative knowledge to this effect during lifeguard training. As an alternative, we propose a novel training tool that requires novice participants to rapidly categorise 3-s video clips of real-life swimmers as either ‘safe’ or ‘drowning’. A control group also completed a sham intervention, with surfers that may ‘fall’. Due to the complex nature of swimming pools, a scaffolded training approach was employed, which gradually increased the amount of background information over subsequent training rounds. Results demonstrated that the drowning classification training improved responses in a subsequent drowning detection test, compared with the active control-group. The scaffolded approach appeared to prepare participants for processing swimmers in the drowning-detection test. The results provide a foundation for a novel training protocol to improve lifeguard skills.     

Sensory and affective judgments of skin during inter- and intrapersonal touch

Here we report two experiments that investigated the tactile perception of one’s own skin (intrapersonal touch) versus the skin of other individuals (interpersonal touch). In the first experiment, thirteen female participants rated, along four perceptual attributes, the skin of their own palm and volar forearm, then that of several of the other participants. Ratings were made using visual analogue scales for perceived smoothness, softness, stickiness, and pleasantness. One’s own skin was rated less pleasant than the skin of others. For both intra- and interpersonal touch, the forearm skin was rated smoother, softer, less sticky and more pleasant than the palmar skin. In the second experiment, ten pairs of female participants rated each other’s palm and volar forearm skin, with the skin of the touched individual being assessed before and after the application of skin emollients that alter skin feel. As in the first experiment, the untreated skin of others was rated more pleasant than the participants’ own skin, and the forearm versus palm differences were replicated. However, the emollient had generally larger effects on self-assessments than the assessments of others, and the site effect showed greater positive sensory and pleasantness increases for palm versus volar forearm. The disparate results of the two experiments suggest that attention, influenced by the ecological importance of the stimulus, is more important to assessment of touched skin than ownership of the skin or the contribution to self-touch made by the additional receptors in the passively touched skin. In both experiments, the pleasantness of touched skin was associated with the skin’s perceived smoothness and softness, with weak trends toward negative associations with its perceived stickiness, consistent with prior research using inanimate surfaces (e.g., textiles and sandpapers).