Thesis / Doctor of Philosophy (PhD)

<p> Three experiments, involving 250 subjects, were performed which support the conclusion that a tone cue presented shortly before a tachistoscopic stimulus facilitates tachistoscopic recognition. With tone-stimulus intervals below two seconds no threshold differences occurred. With intervals between two and eight seconds, the shorter the interval was, the lower thresholds were, and the more practice decrement observed. Experiment II showed that while the tone-stimulus interval affects thresholds the most, the interval between successive exposures of a stimulus affects thresholds. We concluded that as this interval is lengthened, the subject forgets information already gained. Experiment III showed that training in a reaction time task transferred positively to a tachistoscopic task when a two second tone-stimulus interval was used in both tasks. Reasons for the facilitative effect of the tone were discussed.</p> / Thesis / Master of Arts (MA)

Five experiments, involving 265 subjects, were performed with the objective of extending the analysis of response probability as a determinant of the practice effect in tachistoscopic word recognition. The results showed that the response probabilities of words may be manipulated and act as a determinant of the practice effect under certain limited experimental conditions. A more powerful determinant appears to be a general skill in tachistoscopic recognition which improves as a function of the number of stimuli recognized and transfers to the recognition of different stimuli. This skill was examined in the final experiment. The overall results were discussed in terms of both response probability and a general tachistoscopic skill. / Thesis / Doctor of Philosophy (PhD)