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Two studies using different techniques (partial report and backward masking) have found at least some subgroups of schizophrenics deficient in iconic memory. Both hypothesized that the icon in some schizophrenics might be either weakly formed, limited in capacity, or abnormal in duration, but neither study was able to test the qualities of the icon independent of possible transfer difficulties. The present study developed a picture integration task that was analogous to Eriksen and Collins' random dot integration technique. With this task, we were able to assess the capacity and decay of the icon independent of transfer to short-term store. The icon itself was found intact in all schizophrenics. We suggest other explanations for schizophrenics' inadequate partial report and backward masking performance. Knight, Sherer, and Shapiro (1977) investigated iconic imagery in schizophrenics to determine the specific stage of information processing responsible for previously found visual memory differences among schizophrenic subgroups (Knight, Sims-Knight, & Petchers-Cassell, 1977). They presented to three groups of schizophrenics (overinclusives, middle inclusives, and underinclusives) and to a nonpsychotic control group a modification of a paradigm that had been developed by Sperling (1960) to maximize the possibility of tapping a perceptual trace. In this paradigm, Sperling presented supraspan matrices of letters for very short durations. At various intervals after the offset of the stimulus, the subjects were instructed by a signal to report a given row (partial report). At zero delay, the subjects could report with great accuracy the items in the designatedThe authors wish to express their appreciation to the staff of Bedford Veterans Hospital for their cooperation with our project. They also wish to acknowledge the assistance of Susan Boxerman, Lisa Oppenheim, and Ruth Rosenberg.Requests for reprints should be sent to Raymond

Continuous ocular and manual tracking of the same visual target moving horizontally in sinusoids at 0.75 Hz was measured by lag, RMS Error, and Gain. The best measures of accuracy of tracking, error and lag, were remarkably similar in the two systems and were affected similarly by presence of a background and changes in predictability of target movement. Details of within-system performance varied despite the over-all parallels. Gain was different in adjustment of proportion of saccadic to pursuit movement was affected by the presence of the hand, even though this did not affect tracking accuracy. The over-all parallel of response adjustment suggests that a suprasystem decision-maker sets general response goals and each motor system adjusts output details to match these goals.

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