Perception of symmetry in infancy: the salience of vertical symmetry and the perception of pattern wholes

Four experiments were conducted to assess converging aspects of 4-month-old infants' perception of symmetry in visual patterns. Experiments 1 and 2 manipulated the structure and orientation of comparable patterns in order to evaluate the specialty of vertical symmetry. Infants showed no preference among vertically symmetrical, vertically repeated, and obliquely symmetrical patterns, but they processed vertically symmetrical patterns more efficiently than either vertically repeated patterns or obliquely symmetrical patterns. Experiment 3 manipulated the spatial separation of pattern components in order to determine the ability of young infants to integrate and coalesce information in visual patterns that is distributed in space. Infants processed vertically symmetrical patterns whose components were contiguous or nearly contiguous about the vertical axis (0 to 2.5 degrees separations) more efficiently than discontiguous patterns (5 and 10 degrees separations). Thus, extreme spatial separation about the vertical meridian caused infants to lose the advantage for vertical symmetry, and by inference their holistic perception of the visual pattern. Experiment 4 manipulated the organization of individual components of a vertical pattern in order to examine further infants' sensitivity to perceptual organization and synthesis of pattern form. Infants discriminated vertically symmetrical patterns from asymmetrical patterns with a vertical organization, thereby demonstrating sensitivity to the symmetrical organization of the pattern above their perception of components in the pattern. The results of these four experiments together corroborate and extend previous findings that vertical symmetry has a special status in early perceptual development and that infants can perceive pattern wholes.     

Inner speech as a learned skill

Three experiments are reported which address the problem of defining a role for inner speech. Experiments 1 and 2 establish that inner speech is acquired by normally developing readers between the ages of 8 and 11, and that both slow and fast readers show a similar pattern of acquistition, but do so at a different rate from normal readers. We suggest that the development of inner speech accompanies a strategy of reading aloud “with expression”; and that it is a manifestation of the need to prestructure oral utterances. These will thus contain the lexical items visible on the page within an appropriate prosodic envelope. Both segmental and suprasegmental phonemes contribute to meaning of spoken and, by analogy, written language. Experiment 3 showed that children at this critical point in learning to read comprehended text better when certain prosodic features were made visible on the text. Prosodic restructureing may thus be an important skill acquired by young readers as they progress toward fluent, silent adult reading.     

The effect of semantic plausibility on sentence comprehension in aphasia

Tested were 50 aphasic patients (16 Broca's, 15 Wernicke's, 10 global, and 9 amnesic), 13 nonaphasic brain damaged patients, and 13 normal adults to evaluate the effect of semantic plausibility on sentence comprehension in active affirmative declarative sentences with a sentence-picture matching task. A plate of two pictures was provided for each stimulus sentence, and the subject was required to choose the picture corresponding to the sentence presented auditorily. Two types of sentences in terms of plausibility were prepared, i.e., probable sentences (P) describing common events in our daily life and improbable sentences (I) describing rare events. There were four kinds of combinations of a picture with the other to make a correct/(distractor) set, i.e., P/(P), P/(I), I/(P), and I/(I) constructions. The results indicated that probable sentences were more comprehensible than improbable sentences, and that the effect of semantic plausibility did not differ among aphasic types.     

Spontaneous translation and language mixing in a polyglot aphasic

The literature on language mixing in polyglot aphasics is reviewed and a case report of a patient with spontaneous translation is presented. A microgenetic model of language processing provides an interpretive framework for language mixing and spontaneous translation as symptoms of polyglot aphasia. It is suggested that language mixing reflects a deficit at the linguistic level while spontaneous translation reflects a deficit at the prelinguistic level of language processing. A hypothesis about the organization of multiple languages in a single speaker is proposed.     

Focal changes in cerebral blood flow produced by monetary incentive during a mental mathematics task in normal and depressed subjects

The purpose of this experiment was to determine the effect of incentive-induced arousal on the diffuse and regional cerebral blood flow (rCBF) response during cognitive activation for normal and depressed groups. Two normal rest CBF measurements were followed by two mental mathematics activation CBF measurements. For the first activation measurement, half the subjects in each group were offered monetary incentive for correct performance and half the subjects received no monetary incentive. All subjects were offered monetary incentive on the final activation run. The effect of monetary incentive on the first activation run was to increase CBF activation at four detectors in the left hemisphere. Incentive did not affect the CBF activation response when introduced following practice on the activation task (on the final run). Depressed groups had lower resting blood flow than normals, but the distribution of flow and the CBF response to incentive were almost identical in the two groups.     

Interpretation and use of the Luria-Nebraska battery

In a recent article, T. V. Akhutina and L. S. Tsvetkova (1983, Brain and Cognition 2, 129-134) presented an analysis of the Luria-Nebraska Neuropsychological Battery. Along with their generally positive review, they raised questions regarding the importance of the qualitative aspects of patients' performance in the interpretation of the battery. We agree with the authors that any interpretation of the battery which does not consider qualitative performance can limit the power and applicability of the battery. The procedures of item analysis and qualitative analysis are discussed as essential to a comprehensive interpretation of the battery. Also discussed are comments on additional scaling for the battery and the development of a standardized qualitative scoring system.     

The different types of limb apraxia errors made by patients with left vs. right hemisphere damage

Limb apraxia errors were compared among normal controls and right- or left-hemisphere-damaged patients as they imitated gestures with the ipsilateral hand. Both brain-damaged groups made similar errors on nonrepresentative and representative/intransitive movements. In contrast for pretended object use movements (transitive), the left-hemisphere-damaged group made more arm position and classical body-part-as-object errors while the right hemisphere group made as many partial errors and more less-primitive, body-part-as-object errors than the left-hemisphere-damaged group. These results help explain why a certain percentage of right-hemisphere-damaged patients are labeled apraxic, but also suggest that the left hemisphere is more important for integrating intrapersonal space and the “representation” of extrapersonal space.     

Children's identity matching and oddity: assessing control by specific and general sample-comparison relations.

After children in Experiments 1 and 2 learned identity matching or oddity, control by sample-comparison relations was assessed. Tests for generalized control displayed novel samples and two comparison stimuli, one identical to the sample. Specific relations were tested with identical or nonidentical sample-comparison stimuli from one set of stimuli and substitute comparisons from either the other training set or from a novel set. When tests displayed identical stimuli, patterns of comparison selection suggested control by generalized identity and oddity. However, selection patterns varied when stimuli were nonidentical and familiar or novel substitute comparisons were used. Therefore, control by specific relations is not a precondition for generalized identity and oddity. One set of training stimuli was used in Experiment 3, and generalized performances occurred again. Moreover, control by specific relations was shown by the oddity subjects and 2 of 6 identity subjects. Generalized and specific control may therefore exist simultaneously. In Experiment 4, selections were irregular on tests displaying substitute comparisons and samples and familiar comparison stimuli; this finding supported the relational account of specific sample-comparison control found in Experiment 3.     

SCIENCE AND THE FORTUNES OF NATURAL THEOLOGY: SOME HISTORICAL PERSPECTIVES

Abstract. The object is to examine strategies commonly used to heighten a sense of the sacred in nature. It is argued that moves designed to reinforce a concept of Providence have been the very ones to release new opportunities for secular readings. Several case studies reveal this fluidity across a sacred-secular divide. The irony whereby sacred readings of nature would graduate into the secular is also shown to operate in reverse as anti-providentialist strategies invited their own refutation. The analysis is used to support the claim that the sciences have put fewer constraints on religious belief than is generally assumed.     

警惕啊!基因决定论

基因已经成为２０世纪遗传学中的一个关键词基因决定论也正在走近我们的生活本文从遗传学的角度阐述了基因决定论的种种不当之处,并且指出基因的作用与人类的生活方式密切相关,而人类的全部文明史就在于克服单纯的基因决定论所带来的局限。