Biomedical subjects

Amedeo D'Angiulli

Publications and source records attributed to Amedeo D'Angiulli.

6 recordsLinked to original sources

PubMed2004

The depiction of car light beams in a child born completely blind.

A 12-year-old child (DI) who was completely blind from birth, made a series of tactual (raised-lines) drawings of cars. Among them, there was the depiction of a 'fast car at night' in which DI drew beams of light projecting out of the car. We analyse this drawing, and the preceding ones. We argue that the way in which cars and light beams were depicted by DI cannot be fully and solely explained by graphic imprecision, executive or motor deficiencies, or by rote or verbal learning. Instead, we propose that the most plausible explanation is that DI's depiction of light in a fast car at night reflects the child's naïve knowledge of light propagation, and that this knowledge was gained through perceiving light as radiant heat.

Automobiles↗

PubMed2002

Mental image generation and the contrast sensitivity function.

In one experiment, observers were instructed to generate small and large visual mental images in a light-adapted or a dark-adapted viewing condition, and to rate the vividness of each image. In light-adapted viewing, small images were generated faster than large images. However, the pattern of results was reversed in dark-adapted viewing. Furthermore, the dark-adapted images were more vivid than the light-adapted images. The results show that mental images can be mapped onto some regions of the contrast sensitivity function (CSF), so that the latency (and vividness) of a particular image can be predicted. Since the CSF reflects visual processes occurring mainly in V1, the results agree with functional magnetic resonance imaging data in indicating that early visual pathways participate in imagery. Nonetheless, imagery and perception may involve different processes hosted by the same neural structures as indicated by the direct relationship between image latency and contrast sensitivity.

Cognition↗

PubMed2002

Enhanced tactile encoding and memory recognition in congenital blindness.

Several behavioural studies have shown that early-blind persons possess superior tactile skills. Since neurophysiological data show that early-blind persons recruit visual as well as somatosensory cortex to carry out tactile processing (cross-modal plasticity), blind persons' sharper tactile skills may be related to cortical re-organisation resulting from loss of vision early in their life. To examine the nature of blind individuals' tactile superiority and its implications for cross-modal plasticity, we compared the tactile performance of congenitally totally blind, low-vision and sighted children on raised-line picture identification test and re-test, assessing effects of task familiarity, exploratory strategy and memory recognition. What distinguished the blind from the other children was higher memory recognition and higher tactile encoding associated with efficient exploration. These results suggest that enhanced perceptual encoding and recognition memory may be two cognitive correlates of cross-modal plasticity in congenital blindness.

Analysis of Variance↗

PubMed2002

On boredom and experimentation in humans.

This article discusses the ethical and methodological issues associated with boredom experienced by human participants during psychological experiments. Ways are suggested in which informed consent, briefing, and debriefing can be used to prevent or remedy boredom induced during experiments. We address methodological and ethical concerns, and we discuss the advantages of the proposed approach for experimenters' practice and training of undergraduate students. Future directions for much needed research on these topics are also emphasized.

Behavioral Research↗

PubMed2002

Generating visual mental images: latency and vividness are inversely related.

In three experiments, participants pressed a reaction time key and rated vividness after reading descriptions of common objects and imagining them as accurately as possible within a visual display subtending 1.2 degrees or 10.8 degrees. Display size had small effects on vividness and on image latency. Latency was much faster (approximately 2.5 sec) for vivid images than for nonvivid ones (approximately 7.5 sec), regardless of display size and initial size at which the images were generated (natural image size). Our findings characterize images as (1) detailed, as indicated by ratings of detail and by lack of category membership effects; (2) as occurring at many natural image sizes, so that time-consuming size adjustments are typically not needed; and (3) generated not concurrently with but after lexical access, as shown by latencies for the same image evoked by synonyms like pail and bucket. We conclude that image vividness and latency reflect the activation level of the visual imagery system, implying that image generation in everyday life mostly involves retrieving already-computed representations episodically stored in memory, which seldom require extensive re-elaboration such as size adjustment.

Humans↗

PubMedDate not supplied

Cognitive functioning as measured by the WISC-R: do children with learning disabilities have distinctive patterns of performance?

Patterns of performance on the Wechsler Intelligence Scale for Children-Revised (WISC-R) have been proposed as useful tools for the identification of children with learning disabilities (LD). However, most of the studies of WISC-R patterns in children with LD have been plagued by the lack of a typically achieving comparison group, by failure to measure individual patterns, and by the lack of a precise definition of LD. In an attempt to address these flaws and to assess the presence of patterns of performance on the WISC-R, we examined data from 121 children with typical achievement (TA), 143 children with reading disabilities (RD), and 100 children with a specific arithmetic disability (AD), ages 6 to 16 years. The results indicated that the RD and AD groups had significantly lower scores than the TA group on all the Verbal IQ subtests. Many of the children with AD and RD showed a significant difference between Verbal and Performance IQ scores, but so did many of the typically achieving children. Although there were some children with LD who showed the predicted patterns, typically, 65% or more of the children with LD did not. Furthermore, a proportion of the TA group-generally not significantly smaller than that of the RD and AD groups-showed discrepancy patterns as well. Our results indicate that the patterns of performance on intelligence tests are not reliable enough for the diagnosis of LD in individual children. Therefore, it might be more profitable to base the detection of an individual's LD on patterns of achievement test scores.

Adolescent↗