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C H Dent

Publications and source records attributed to C H Dent.

16 recordsLinked to original sources
PubMed1990

An ecological approach to language development: an alternative functionalism.

I argue for a new functionalist approach to language development, an ecological approach. A realist orientation is used that locates the causes of language development neither in the child nor in the language environment but in the functioning of perceptual systems that detect language-world relationships and use them to guide attention and action. The theory requires no concept of innateness, thus avoiding problems inherent in either the innate ideas or the genes-as-causal-programs explanations of the source of structure in language. An ecological explanation of language is discussed in relation to concepts and language, language as representation, problems in early word learning, metaphor, and syntactic development. Finally, problems incurred in using the idea of innateness are summarized: History prior to the chosen beginning point is ignored, data on organism-environment mutuality are not collected, and the explanation claims no effect of learning, which cannot be tested empirically.

Child Language↗
PubMed1990

Papular acne scars. A common cutaneous finding.

One hundred thirty-three patients were examined for the presence of a cutaneous eruption consisting of small, asymptomatic, hypopigmented, follicular papules on the upper part of the trunk. The papules were present in 57% of patients who had a history of acne vulgaris and in 9% of patients who denied ever having had acne. Biopsy specimens from five patients revealed circumscribed, perifollicular or parafollicular lesions in which both elastic and collagen fibers were attenuated in comparison with those in normal adjacent dermis. These changes are consistent with scar. We conclude that the papules are a scarring process secondary to acne vulgaris and propose calling the lesions papular acne scars. They appear closely related to or identical with changes previously termed perifollicular elastolysis, postacne anetoderma-like scars, and papular elastorrhexis.

Acne Vulgaris↗
PubMed1988

A mechanism for the direct perception of change: the example of bacterial chemotaxis.

The relationship between the behavior of single-celled organisms and cognition in higher animals is explored. Recent research and theory in bacterial chemotaxis are presented, together with a discussion of the implications of chemotaxis for perceptual theory. A number of parallels between chemotaxis and perception in higher organisms are drawn. It is suggested that Koshland's model of the chemical processes controlling chemotaxis is an example of a mechanism for direct perception of change and can help elucidate Runeson's work on 'smart mechanisms' of perception. It is argued, more generally, that the growing body of knowledge about the perceptual activities of lower organisms should be used to broaden the factual base on which theories of perception are constructed: eg explication of perceptual parallels between humans and lower organisms should help clarify the nature of these phenomena in humans and, perhaps, help in the development of theories of greater generality. Also, the debate between direct and indirect theories of perception may be advanced by analysis of the specific mechanisms used by lower organisms. Contrasts to mediated perception are pointed out and arguments for the relative simplicity and explanatory power of theories of direct perception are provided.

Animals↗
PubMed1984

The developmental importance of motion information in perceiving and describing metaphoric similarity.

The perceptual basis of metaphor was investigated using films of natural objects and events. The subjects were 5-, 7-, and 10-year-old children and adults, 16 at each age. The stimuli were 10 triads of films, for example, a ballerina spinning, a top spinning, and a ballerina leaping. There were 3 possible pairs of scenes: the metaphoric (e.g., ballerina spinning, top spinning), the literal (e.g., ballerina spinning, ballerina leaping), and the control (e.g., ballerina leaping, top spinning). Half the triads were stationary objects, the other half moving objects (i.e., events). Subjects were asked to pair scenes and talk about them. The mean frequency of metaphoric pairings increased with age, literal pairings increased from ages 5 to 7, and control pairings were consistently infrequent. Event triads elicited more metaphoric pairings than object triads, and the frequency of event metaphoric pairings was equal to event literal pairings at a younger age. Figurative language increased in frequency from ages 5 to 10, and figurative words more often referred to action in the event than in the object triads. It was concluded that motion information made metaphoric similarity relatively easy to perceive and influenced the form of descriptive metaphors.

Age Factors↗