A simple technique for lateralizing visual input that allows prolonged viewing

A simplified technique is described for obtaining lateralization of visual input with prolonged viewing. This technique is based on the presence of constant normal lateral limits for horizontal rotation of the eyes with reference to the head. With head movement prevented by use of a standard bite bar, and the eyes rotated to the left and held at their lateral limit, the temporal half of the visual field of the left eye may be used for lateralized input to the right hemisphere or vice versa for input to the left hemisphere. Any form of visual stimuli or visually monitored task can be used if confined within one of the extreme temporal hemifields. In comparison to previous methods, this technique is technically simple, inexpensive, without significant risk or discomfort to the subject, readily applicable to normal and various brain-lesioned subjects, and permits prolonged in-depth viewing. An alternative version of this technique uses a stabilized spectacle frame fitted with adjustable central occluders set to allow vision through only one or both of the extreme temporal hemifields.     

Word superiority in word detection

Observers searched for a single precued word or its nonword anagram under conditions of rapid serial visual presentation (RSVP). A word advantage was found over a wide range of presentation rates (32-160 msec/frame), under yes-no as well as forced choice conditions, and with both one or two input “channels.” These results suggest that word superiority in word detection occurs at a perceptual locus.     

Imaginary companions in childhood and adult creativity.

Case material is presented to illustrate the thesis that the ability to create an imaginary companion during childhood is an early expression of the special ego aptitudes found in creative individuals in adult life. Such "companions" allow these children to attempt to master creatively a variety of narcissistic mortifications suffered in reality and to displace unacceptable affects. In creative adults who had imaginary companions in childhood, the early fantasies serve as an organizing schema in memory for the childhood traumata. Stimuli in adult life which evoke the earlier traumata may revive the original imaginary companion fantasies. These then serve as nodal bases for the creation of specific adult works of art.     

Word and nonword superiority effects in a letter detection task

Subjects searched for predesignated consonant letters embedded in strings of consonants, consonants and vowels, or consonants and numbers. In Experiments 1-3, detection was quicker in the consonant-vowel and consonant-number strings than in the consonant strings. Apparently, vowels and numbers were less confusable distractors than are nontarget consonants. Experiment 4 tested whether psychophysical or categorical information about letters and numbers enabled subjects to process consonant-vowel and consonant-number strings more quickly. Results indicated that psychophysical characteristics of target and distractor letters mediated both word and nonword superiority effects.

     

Two kinds of adaptation in the constancy of visual direction and their different effects on the perception of shape and visual direction

Adaptation in the constancy of visual direction can be obtained under two radically different conditions, called eye-movement adaptation and field adaptation. Adaptation resulting from these conditions and from a “normal” condition was measured with a newly developed estimation test. Eye-movement adaptation was found to cause an alteration of compensatory eye movements. It apparently consists of a changed evaluation of eye movements, as demonstrated by two different pointing tests. A form test where the shape of a large oblong is set to look square also confirmed this interpretation. After field adaptation, a pointing test did not register a change, but an adaptation effect could be measured with a forward direction test. This test and a square test where no eye movements were permitted proved to be specific to field adaptation; they measured no effect after eye-movementadaptation. The normal adaptation condition Was apparently equivalent to the eye-movement adaptation condition. Its effect could be measured only with a pointing test. When we changed the normal adaptation condition so that frequent saccades were made during head turning, strong effects were measured with the two tests that were specific to field adaptation.     

Stimulus and response factors in mirror-image discrimination

Two choice-reaction time studies assessed the influence of stimulus-response mapping, stimulus complexity, and stimulus alignment on adults’ discrimination of mirror-image and nonmirror-image stimulus pairs. Half the subjects in Experiment 1 were instructed to treat nonmiiTor pairs as “same” and mirror pairs as “different”; the other half responded in the opposite manner. The first group responded more quickly to nonmirror pairs, while the second group responded more quickly to mirror pairs. This result, which held for horizontal stimuli (side by side) as well as for vertical stimuli (one above the other), confirms the importance of experiential factors in mirror-image “confusions. “ In Experiment 2. stimuli were drawn from a population of patterns whose complexity could be objectively defined. In general, the more complex the pattern, the slower the response and complexity seemed to influence the qualitative nature of pattern processing. In both experiments, subjects responded more quickly to horizontal stimuli than to vertical stimuli.     

Imaginary companions, fantasy twins, mirror dreams and depersonalization.

Illustrative case material is presented to demonstrate genetic linkages between the presence of imaginary companions or fantasy twins and extensive mirror play in childhood and early adolescence, and the appearance of mirror dreams and depersonalization in later adolescence and adulthood. The defensive splitting of the self-representations observable in these phenomena is viewed as a means of warding off castration anxiety and anxiety about object loss, anxieties which arise because of conflicts primarily centering on intense aggressive drive derivative wishes. Formulations about depersonalization are discussed.