How much help do repeated presentations give to recognition processes?

Abstract

A recent experiment by Haber and Hershenson (1965) Research on temporal integration (e.g., Boynton, 1961) has suggested that within the integration period, it does not matter how presentations are distributed in time. Thus, two 10-msec. flashes are equivalent to one 20-msec. flash, and further, the separation between the two 10-msec. flashes is irrelevant as long as the total time from onset of the first to offset of the second does not exceed the integration constant. The value of the integration constant depends, of course, upon the relative luminances of the target and adaptation fields, as well as on the task of the perceiver (absolute threshold, judgment, discrimination of successiveness, brightness matching), but generally the upper limit is around 100 msec, Within this time then it is possible to chop up the total energy package and redistribute it helter-skelter in time without affecting the perceiver's responses to it.A similar kind of investigation can be pursued about a seemingly unrelated problem. Assume an energy package of fixed luminance, and of a duration of 50 msec., for example. Is the perceiver equally as efficient in recognizing the content of the stimulus in one presentation of 50 msec., as in two well separated (e.g., one-to-ten sec. apart) presentations of 25 msec., as in four presentations of 12-1/2 msec., etc.? Since these interstimulus intervals are several orders of magnitude larger than the integration constant, the answer would seem to be "no."However, some recent data showing the effect of repetition on word and letter recognition suggest that perhaps the "no" may be too hasty. A series of studies by Haber and Hershenson (1965), Hershenson and Haber (1965), Haber (1965), Haber and Hillman (1966) and Hershenson (1965), have shown that if words or letters are presented for from one to 25 times, with no change in duration or luminance, the clarity of the letters increases dramatically as a function of the number of repetitions. Thus, holding energy constant, the clarity of the letters of the stimulus increases with repetitions alone, even when the repetitions are spaced as much as 10 sec. apart. This effect is found with frequent English words, with Turkish words, with rare English words, with rare and frequent English words for which the subject is clearly shown each word just prior to its first presentation, with single English letters, and with three and four letter nonsense words. Further, in each case, the rate of increase in clarity of the letters of the stimuli follows the same mathematical function, indicating that the effect of repetition is independent of the structure and meaning of the stimulus. (See Haber, 1966a, for a summary of the earlier of these studies, and Haber, 1966b, for a more detailed discusston.)The relevance of these studies comes from the fact that repetition will increase the clarity of an item of the stimulus without changes in the intensity, duration, or other stimulus characteristics. Therefore, one can ask whether a reciprocity exists between these ene...

Repetition and laterality effects on recognition memory for words and pictures*

“…that indicate that the time taken for stimulus encoding and initial retrieval processes should be less for repeated stimuli than for stimuli presented for the first times in the context of the experiment. Studies of recognition thresholds for visual stimuli have shown that repetitions facilitate stimulus identification (Haber & Hershenson, 1965: Dainoff & Haber, 1967. Repetitions of stimuli in choice reaction time (CRT) tasks have resulted in faster response times (e .g.. Bertelson, 1963), and this effect is obtained even if several presentations of different stimuli intervene between successive presentations of a given test stimulus (Remington, 1969).…”

Relationship of visual and name similarity of visually presented letters

“…The purpose of the mask was to interfere with the iconic image of the letters so that the presented stimulus duration approximated the effective stimulus duration. Since Dainoff and Haber (1967) have presented evidence that stimulus duration plays a greater role than does repetition of the stimulus, it was felt that this method of presenting the data would allow examination of ID coding phenomena at very brief exposure durations. Subsequently, it was noted that the decision as to when to respond might differ at different stimulus duration conditions and from S to S. Since the stimulus duration conditions are likely to be confounded with response decision criteria, data on Stimulus Duration Conditions by Similarity trends are difficult to interpret and will not be reported.…”

The effect of visual masking on the critical duration of form

“…It appears that for brightness perception the simple multiplicative laws (e.g., Blochs & Riccos' law) are determined solely by the total amount of energy which reaches the retina irrespective of how the energy is distributed within the critical duration (Blackwell, 1963;Lichtenstein & Boucher, 1960). Form perception, on the other hand, does not seem to be determined solely by the total amount of energy which reaches the retina, but it is more important that the retina receives sustained stimulation over a critical period (Dainoff & Haber, 1967;Schurman, Eriksen, & Rohrbaugh,1968).…”