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T C Toppino

Publications and source records attributed to T C Toppino.

11 recordsLinked to original sources
PubMed1994

A new twist on the rotating-trapezoid illusion: evidence for neural-adaptation effects.

In a series of experiments, the selective-adaptation paradigm was applied to the rotating-trapezoid illusion in an effort to demonstrate neural-adaptation effects in the figural reversal of this classic illusion. Prior to viewing the standard trapezoid, the observer adapted to a rectangle rotating unambiguously in the same direction as the trapezoid or in the opposite direction. In accordance with the neural hypothesis, illusion strength was greatest when the two figures rotated in the same direction and weakest when the two figures rotated in opposite directions. Results were confirmed with two separate dependent variables: the observer's 'first look' at the illusion after adaptation and the observer's reversal rate during a test period. These findings were discussed in terms of (a) the basic similarity of results for the rotating trapezoid and reversible figures such as the Necker cube and (b) the need for a multiprocess model of both classes of illusions which emphasizes bottom-up and top-down processes.

Adaptation, Ocular↗
PubMed1994

Adaptation effects and reversible figures: a comment on Horlitz and O'Leary.

Horlitz and O'Leary have provided further evidence for the important role of such top-down processes as attention and familiarity on reported reversals of ambiguous figures. As such, these results are consistent with the claims of several other investigators who have argued that any theory of phenomenal reversal that is based solely on passive neural processes is likely to be incomplete. However, Horlitz and O'Leary make the additional claims (1) that the several reports of adaptation effects in the literature are readily reinterpreted within an information-access framework and (2) that their own empirical work demonstrates a basic failure of neural-adaptation effects with reversible figures. It is proposed here that these claims must be viewed with caution. First, Horlitz and O'Leary's explanation for the discrepancy of their results from those of ostensibly similar experimental procedures in the reversible-figure literature is not the only, or the most likely, possibility. A plausible alternative model that posits critical procedural differences (specifically, duration of adaptation) across studies has been offered, and supporting empirical work for this latter suggestion has been presented. Second, the empirical efforts of Horlitz and O'Leary, while providing further evidence for top-down processes, do not eliminate the likely role of adaptation effects with reversible figures. There is strong reason to believe that the viewing conditions selected by these researchers may not have been sufficient to produce appreciable adaptation. Moreover, there is excellent reason to believe that both bottom-up and top-down processes moderate reported reversals of these figures.(ABSTRACT TRUNCATED AT 250 WORDS)

Attention↗
PubMed1992

Prime time: fatigue and set effects in the perception of reversible figures.

Subjects viewed unambiguous versions of both stationary and rotating Necker cube illusions for varying durations prior to the presentation of the standard ambiguous figure. In each case, the subjects were more likely to report the ambiguous figure to be (1) in the same configuration as that of the preceding prime following brief preexposure periods and (2) in the opposite configuration from that of the preceding prime following long preexposure periods. In addition, the number of reversals of the figure during the test period was also strongly related to the duration of the preexposure period, with progressively fewer reversals reported following longer preexposure periods. The results are interpreted as revealing the concurrent roles of "set" effects in the brief preexposure conditions and neural fatigue effects in the long preexposure conditions. Furthermore, the ability of the proposed two-process model to integrate the myriad of empirical effects in the reversible-figure literature is emphasized.

Adult↗
PubMed1991

The effect of spacing repetitions on the recognition memory of young children and adults.

In Experiment 1, preschoolers, first graders, and third graders were presented a list of pictures that included twice-presented items separated by varying numbers of intervening items. Performance on a subsequent recognition test improved as the spacing between repetitions increased, but the effect of spacing did not interact reliably with grade level. In Experiment 2a, we replicated the spaced-repetition effect in young children and found a similar effect in college students. In Experiment 2b, we varied the conditions under which lists were presented to college students and again found a spacing function that was comparable to that of very young children. The results are consistent with the hypothesis that spaced-repetition effects in recognition are produced by fundamental memory mechanisms that are operational at a very early age and which undergo little change with development.

Adult↗
PubMed1991

The spacing effect in young children's free recall: support for automatic-process explanations.

The effect of spacing repetitions on children's free recall was investigated in two experiments. In Experiment 1, both 4-year-old children and 7-year-old children exhibited a spacing effect in free recall, and the magnitude of the effect did not change with age. In Experiment 2, free recall was examined as a function of spacing, age (3 years old vs. 4 years old) and presentation rate (1 vs. 2 vs. 5 sec per stimulus). A spacing effect was obtained that did not differ as a function of age or presentation rate. Of particular interest was the fact that 3-year-olds exhibited a strong spacing effect even when stimuli were presented at a very rapid 1-sec rate. The results support the hypothesis that fundamental memory mechanisms that operate relatively automatically are sufficient to produce a spacing effect in free recall.

Child↗
PubMed1985

The lag effect and differential organization theory: nine failures to replicate.

In our first experiment, we tried to replicate and extend previous results that had provided seemingly convincing support for a differential organization explanation of the monotonically increasing lag effect in free recall. However, we failed to obtain the lag effect. Eight additional experiments also failed to replicate the lag effect. In all, we made 918 observations of performance on items repeated at each of three lags, and the mean percentage of correct free recall varied by less than one percentage point. These results suggest that there are boundary conditions limiting the generality of the monotonically increasing lag effect in free recall. In addition, caution should be exercised in accepting certain previous findings as strong evidence for a differential organization explanation of the phenomenon.

Cues↗
PubMed1981

Multiple representations of the same reversible figure: implications for cognitive decisional interpretations.

Observations are reported with the side-by-side presentation of rotating Necker cubes and other well-known reversible (ambiguous) figures. The fact that the two representations can be seen in the opposite direction of rotation, or perspective, at the same time is regarded as a serious difficulty for the cognitive or decisional interpretations of the spontaneous alternations in these figures. It is suggested that separate and fatiguable cortical 'channels' are a more likely basis for the dual-presentation effect than multiple decisional or attentional processes. The relationship between this proposal and recent research consistent with the visual system as a multichannel processor is noted.

Cognition↗