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G C Shyi

Publications and source records attributed to G C Shyi.

5 recordsLinked to original sources

Global and local processing of incidental information and memory retrieval at 6 months.

In five experiments, we examined the role of global and local cues in memory retrieval in infancy. Six-month-old infants were trained at home in a distinctive context (playpen liner) to kick to move a mobile. The liners were yellow and displayed either green stripes, green squares aligned vertically in stripe-like columns, or green squares in a grid pattern. The stripes and columns liners had a similar global configuration but different local components; the columns and grid liners had identical local components but different global configurations. When infants were tested 24 h after training in the presence of context liners that differed from the training context in either global configurations or local features, their memory retrieval was disrupted (Experiments 1 and 2). However, a change from stripes to columns failed to disrupt memory retrieval, even though the reverse change, from columns to stripes, did. Experiments 3, 4, and 5 revealed that this asymmetry was due to the fact that, when discriminative local information is not directly associated with training, a postperceptual strategy enables infants to disregard a mismatch in local information between training and test contexts and to generalize on the basis of a match in global information during the 24-h retention test. Thus, infants encode and remember for substantial periods of time both global configuration information and local component information in the incidental context in which an event occurs and flexibly utilize this information when responding to new events.

Color Perception↗

Mental extrapolation and representational momentum for complex implied motions.

A sequence of static displays implying consistent motions of a pattern induces distortions in memory for the last-observed appearance of the pattern. These memory distortions suggest that there is an internal analogue to physical momentum called representational momentum. Two experiments are reported comparing performance on tasks in which observers must remember the final display with those in which they are instructed to extrapolate the implied motions out to the next step in the sequence. In each experiment, the memory shifts were highly correlated with the actual rates at which the implied motions were extrapolated. In addition, the memory shifts were larger when the mental extrapolations occurred along the same directions of implied motion each time. These findings suggest that the memory shifts depend both on the rate at which the mental extrapolations are performed and on how consistently they are performed.

Form Perception↗

Implied velocity and acceleration induce transformations of visual memory.

In this study, the phenomenon of representational momentum (Freyd & Finke, 1984) is investigated in cases where visual memories are distorted by implied motions of the elements of a pattern. Our theory predicts that these memory distortions should be sensitive not only to the direction of the implied motions but also to changes in the implied velocity. Subjects observed a sequence of dot-pattern displays that implied that the dots were moving at either a constant velocity or constant acceleration, but in separate directions. Discrimination functions for recognizing the final pattern in the sequence revealed that subjects' memories had shifted forward, corresponding to small continuations of the implied motions. The induced memory shifts increased in size as the implied velocity and acceleration of the dots increased, but were eliminated when the display sequence implied a deceleration of the dots to a final velocity of zero. These findings suggest that mentally extrapolated motion may have some of the same inertial properties as actual physical motion.

Acceleration↗