Is visual information integrated across saccades?

After subjects established fixation on a target cross, 12 dots were presented parafoveally. When the dots were presented, the subjects made an eye movement to the location of the dots, and during the saccade the 12 initially presented dots were replaced by 12 other dots. The 24 dots were part of a 5 × 5 matrix, and the task of the subject was to report which dot was missing. The data were consistent with other recent studies: subjects could successfully report the location of the missing dot far above chance (54%), whereas performance in a control condition (in which the two sets of dots were presented to different spatial and retinal locations) was almost at chance level (10%). However, a number of control conditions demonstrated that the effect was due primarily to persistence from the phosphor of the cathode ray tube used for stimulus presentation and that little of the visual information integrated was across two fixations. Implications of the results for a theory of integration across saccades are discussed.     

Recognition memoryfor pictorial events

Subjects viewed sequences of slides depicting everyday events, and in later recognition tests, they correctly rejected distractors that were inconsistent with some invariant of the event but falsely accepted consistent distractors. J. J. Jenkins has accounted for the differential recognition of consistent and inconsistent slides of pictorial sequences in terms of fusion, the abstraction of an event from a series of temporally related items. The conditions under which event fusion was likely to occur were manipulated in three experiments: degree of ordering of the action-sequence slides, semantic vs. nonsemantic orienting tasks during acquisition, and duration of retention interval Recognition performance was generally more accurate under conditions of semantic processing, ordered acquisition sequences (for the semantic task), and shorter retention intervals. However, these variables did not affect differential recognition of consistent vs. inconsistent slides. A further experiment showed that the absence of an effect of disordering acquisition sequences on differential recognition could not be attributed to subjects’ reordering the disordered sequences in a way consistent with the original event. The data did not support the hypothesis that recognition performance was based on fusion of events depicted by temporally ordered slide sequences. It was suggested that memory for featural detail is a relevant factor in performance.     

Prominent publications in cognitive psychology

This article identifies the 50 publications in cognitive psychology that were most frequently cited in the professional literature between 1979 and early 1982. The characteristics of these publications are discussed, and comparisons are made with other relevant findings.     

Mouse killing in rats induced by lesions of the medial hypothalamus or medial accumbens: short-term preoperative exposure to a mouse does not suppress the killing

Rats were either exposed or not exposed to a mouse in their living cage for a 48-hr period. At the end of this time a bilateral lesion was made in the medial accumbens region or in the medial hypothalamus. When tested 2 days postoperatively, the killing frequency among rats that had been exposed to mice preoperatively was not significantly lower than that of rats that were not preoperatively exposed. The ineffectiveness of preoperative experience in suppressing the mouse killing induced by medial accumbens and medial hypothalamic lesions is similar to that found previously with dorsal-median raphe lesions and olfactory bulb lesions and is in contrast to the ease with which preoperative experience prevents mouse killing induced by septal lesions and serotonergic lesions induced by 5,7-dihydroxytryptamine.     

Sexual activity and contraceptive use among low-income urban black adolescent females.

A modified form of Nathanson and Becker's (1983) Health Belief Model Questionnaire and other measures designed to assess cognitive processing were administered to low-income black adolescent female clients of an inner-city comprehensive health care clinic. The purpose of the study was to explore determinants of sexual activity and contraceptive use. Subjects were classified as not sexually active (n = 50), sexually active/noncontracepting (n = 20), or sexually active/contracepting (n = 72). Not sexually active subjects tended to be younger, more career motivated, to have a father at home, to be more influenced by family values, and to have more conservative attitudes regarding adolescent sexuality than did sexually active subjects. Sexually active/noncontracepting subjects tended to report fewer benefits and more barriers to the use of contraception. Level of cognitive processing did not differ among the three groups, but was at a lower-than-expected level for age. Finally, inconsistent contraceptive use was common to both sexually active groups.     

Making and correcting errors during sentence comprehension: Eye movements in the analysis of structurally ambiguous sentences

Eye movements were recorded as subjects read sentences containing temporary structural ambiguities. In accord with the garden-path theory of sentence comprehension, shorter reading times were found for sentences conforming to certain independently motivated parsing strategies (late closure and minimal attachment) than for comparable sentences which violate these strategies. Further, longer fixation durations were associated with the very first fixation in the region of the sentence which disambiguated the sentence, suggesting that the human sentence-parsing mechanism operates in a rather systematic fashion, immediately computing the structural consequences of fixated material for the analysis of preceding material. The pattern of regressive eye movements did not conform to the view that the parsing mechanism automatically returns to the beginning of the sentence to revise an incorrect analysis of linguistic material nor did it support the view that the parsing mechanism systematically backtracks through the sentence until the source of the erroneous analysis is located. Rather, the pattern of regressions indicated that the parsing mechanism typically engages in selective reanalysis, exploiting whatever information it has available about the type of error it has committed to guide its reanalysis attempts. Finally, it is emphasized that an understanding of the parser's revision procedures is essential to an explanation of why certain linguistic structures cannot be successfully parsed by humans.     

Information flow in the brain: Computer requirements (A tutorial)

This paper covers mathematical, statistical, and experimental design considerations needed to design a computer system for EEG data acquisition, spectrum, and cross-spectrum analyses. A tutorial approach is used in which no formal proofs are offered. Conclusions are stated simply and in summary fashion, without justifying arguments. References to formal works are given. Conclusions about system design are discussed. Frequently encountered design issues are mentioned with various alternatives.