Visual object recognition in patients with right-hemisphere lesions: axes or features?

An investigation is reported of the ability of normal subjects and patients with right-hemisphere lesions to identify 3-D shadow images of common objects from different viewpoints. Object recognition thresholds were measured in terms of angle of rotation (through the horizontal or vertical axis) required for correct identification. Effects of axial rotation were very variable and no evidence was found of a typical recognition threshold function relating angle of view to object identification. Although the right-hemisphere-lesion group was consistently and significantly worse than the control group, no qualitative differences between the groups were observed. The findings are discussed in relation to Marr's theory that the geometry of a 3-D shape is derived from axial information, and it is argued that the data reported are more consistent with a distinctive-features model of object recognition.     

Spatial attention in vision

Summary Human observers can selectively allocate processing resources to different areas of the visual field within a single fixation. This spatial attention system may affect either the quality of information extraction or the decisions and responses based on this information. This paper reviews evidence from behavioral, single-unit, and event-related potential paradigms; the evidence suggests a relatively early locus of spatial attention.This research was supported by the U. S. Army Research Office under contract DAAG 29-83-K-0049. Portions of this paper were presented to the Conference on Attention and Action, Bielefeld, West Germany, in July 1985     

RELIGIOUS EXPERIENCE, ARCHETYPES, AND THE NEUROPHYSIOLOGY OF EMOTIONS

Abstract. Established religions integrate a society's everyday secular realities with humankind's numinous experience of the holy. Powerful emotions nourish the cultural expression of the archetypes propelling the "ritual dances" of art, sport, and technocracy. During sacred moments such as mother-infant or adult bonding, neuroendocrine triggers activate lifelong ties. The cultural canon of the left cortex contrasts with the intuitive right. Brainstem "switches" alternate the left's cool, extraverted, sympathetic drive for control with the right's "warm" attachment behavior and dreaming sleep. Psychic trauma damages flexibility with resultant alexithymic blindness to emotions and archetypes. Substance abuse and narcissistic overemphasis on control ensue.     

How much and how fast: rapid processing of spoken language in later adulthood

Speech processing involves rapid decoding and construction of meaning from a transitory acoustic signal. Because older adults have been found to be slower in performing many cognitive tasks, we hypothesized that they may have difficulty in immediate recall for speech of increasing input rate. Two experiments are reported in which both older and younger participants listened to and immediately recalled sentences that were systematically varied in speech rate and number of propositions. Although recall performance of the older adults showed a disproportionate decline when speech rate was increased, older adults, as well as the younger adults, were able to recall sentences of increasing propositional densities. We also found that the tendency to recall a greater proportion of main ideas than details (the levels effect) was enhanced by increased propositional density, and depressed by increased speech rate and increased age. These results are discussed in terms of an age-related change in the rate at which information can be processed in working memory.     

Induction,trance, and ritual in family mythologizing

The authors put forward a theory of family mythologizing as a process of induction, trance, and ritual. These phenomena, in the context of expressive language, comprise myths. Mythologizing is assumed to be part of normative development. All individuals and families employ myths as schemata for organizing highly complex yet cognitively inexplicable relationships. The authors propose a systemic explanation for the operations of mythologizing and present case illustrations.     

Seeing textons in context

Texton theory holds that visual texture segregation occurs through the preattentive detection of local differences in primitive visual units called “textons.” Three textons have been proposed for shape: lines, line terminators, and line intersections. The experiments reported here show that line closure also behaves like a texton under some conditions. In addition, the experiments show that texture segregation is not determined by texton differences per se, but by the extent to which the unique textons in a region are salient in the context of the textons common to regions. This suggests that preattentive vision is not as simple minded as texton theory claims it to be.     

The electronic chalkboard

The present paper describes “the electronic chalkboard” (TEC), a teaching innovation made possible by the recent development, under a FIPSE grant to CONDUIT, of specialized instructional software. The instructional power of TEC casts the computer in the role of catalyst in the student-teacher dyad and leads to the emergence of the more powerful student-computer-teacher triad. Relevant educational principles and CAI techniques that should ensure the intelligent use of TEC are discussed.