Precise Worlds for Certain Minds: An Ecological Perspective on the Relational Self in Autism

Topoi - Autism Spectrum Condition (ASC) presents a challenge to social and relational accounts of the self, precisely because it is broadly seen as a disorder impacting social relationships. Many...     

Beneficial and adverse effects of pets

The beneficial and adverse effects of pets on people with special mental and physical conditions merit inclusion in psychological evaluations and treatments.     

Perception of pictorial eye gaze by baboons (Papio papio)

Pictorial faces looking left or right were presented to baboons (Papio papio) before the display of a target letter in the left or right hemifield of a monitor screen. Baboons had to provide go or no-go responses taking into account the identity of the target letter. The 1st 6 experiments showed no reliable effect of eye gaze on discrimination speed, using either schematic gazes or pictures of real gazes. Experiment 7 showed that eye gazes facilitated target processing when eye cues were perfect predictors of target location. Findings suggest that baboons do not spontaneously process eye-gaze direction but can learn to do so if the gaze has a predictive value. Implications of these findings on baboons' perspective-taking abilities are discussed.     

Using the PAI with an eating disordered population: scale characteristics,factor structure,and differences among diagnostic groups

Psychometric properties of the Personality Assessment Inventory (PAI; Morey 1991) within an eating disordered sample seeking treatment (N = 238) and differences among eating disorder diagnostic groups on the PAI were examined. The PAI showed acceptable alpha coefficients, item-total correlations, and interitem correlations. The factor structure was similar to that reported by Morey (1991), with the addition of another factor related to interpersonal coolness and distance. Those with binge eating disorder (BED) reported fewer problems and less distress in general compared to other eating disordered groups. The BED and bulimia nervosa groups were different from the anorexia nervosa groups in frequency of matching on two PAI clusters. Use of the PAI with an eating disordered population and its utility in understanding eating disorder diagnostic groups is supported.     

Cascaded versus noncascaded models of lexical and semantic processing: the turple effect

The density of the orthographic neighborhood surrounding an item has been shown to have an inhibitory effect for nonwords in a lexical decision experiment. Four experiments are reported investigating whether a similar pattern holds for a semantic categorization task (animal vs. non-animal). In the first experiment, no effects of neighborhood density were found for nonexemplars, whether they were words or nonwords. The absence of any inhibitory effect for nonwords implies that close orthographic neighbors are ignored. However, the second experiment showed that if the nonword has a neighbor that is an animal name (eg., turple), an interference effect is observed, implying that neighbors do exert an effect if they have the right semantic properties. The same items showed no additional interference in lexical decision. These results suggest the involvement of semantic properties very early in the processing cycle. A cascaded processing system monitoring activation in semantic features can explain these results, but cannot explain the frequency effect observed for nonexemplar words or the fact that variation in density is irrelevant when one of the neighbors is an exemplar. It is argued that existing models of semantic categorization must be extended to accommodate these results.     

Testing comprehension abilities in users of British Sign Language following CVA

Recent imaging (e.g., MacSweeney et al., 2002) and lesion (Hickok, Love-Geffen, & Klima, 2002) studies suggest that sign language comprehension depends primarily on left hemisphere structures. However, this may not be true of all aspects of comprehension. For example, there is evidence that the processing of topographic space in sign may be vulnerable to right hemisphere damage (e.g., Hickok, Say, Bellugi, & Klima, 1996), and the influence of iconicity on comprehension has yet to be explored. In this study, comprehension testing was conducted with 15 signers with unilateral brain damage, and with elderly Deaf controls. Four tests were administered: a test of iconic and non-iconic noun comprehension, a test of verb and sentence comprehension, a test of locative sentence comprehension, and a test of classifier comprehension. All tests were administered in British Sign Language (BSL), a language that has only recently been explored with lesioned signers (see Atkinson, Marshall, Thacker, & Woll, 2004; Marshall, Atkinson, Thacker, Woll, & Smulevitch, 2004; Marshall, Atkinson, Woll, & Thacker, in press). People with left hemisphere damage were impaired relative to controls on all tests. Those with right hemisphere damage performed well in the first two tests, but were impaired on locative sentences and classifiers. Neither group showed any effect of iconicity. The results shed further light on the laterality of sign language comprehension.     

Impaired verb fluency: a sign of mild cognitive impairment

We assessed verb fluency vs. noun and letter-based fluency in 199 subjects referred for cognitive complaints including Subjective Cognitive Impairment, Mild Cognitive Impairment, and Alzheimer's disease. ANCOVAs and factor analyses identified verb, noun, and letter-based fluency as distinct tasks. Verb fluency performance in Mild Cognitive Impairment differed significantly from Subjective Cognitive Impairment and Alzheimer's disease. Reduced verb fluency thus appears to be a linguistic marker for incipient dementia. One possibility is that the verb fluency deficit in Mild Cognitive Impairment results from degenerative processes known to occur in the parahippocampal region.     

Geometric and perceptual effects of the location of the observer vantage point for linear-perspective images

New geometric analyses are presented of three impressive examples of the effects of location of the vantage point on virtual 3-D spaces conveyed by linear-perspective images. In the 'egocentric-road' effect, the perceived direction of the depicted road is always pointed towards the observer, for any position of the vantage point. It is shown that perspective images of real-observer-aimed roads are characterised by a specific, simple pattern of projected side lines. Given that pattern, the position of the observer, and certain assumptions and perspective arguments, the perceived direction of the virtual road towards the observer can be predicted. In the 'skewed balcony' and the 'collapsing ceiling' effects, the position of the vantage point affects the impression of alignment of the virtual architecture conveyed by large-scale illusionistic paintings and the real architecture surrounding them. It is shown that the dislocation of the vantage point away from the viewing position prescribed by the perspective construction induces a mismatch between the painted vanishing point of elements in the picture and the real vanishing point of corresponding elements of the actual architecture. This mismatch of vanishing points provides visual information that the elements of the two architectures are not mutually parallel.