Parallels between remembering and predicting an object's location

Phasic alertness boosts representational momentum

The final location of a moving object is always misremembered in the direction of the object’s motion; this occurrence is called representational momentum. Three experiments were conducted to investigate the effects of phasic alertness on representational momentum by presenting a visual or auditory warning cue. In experiment 1, the mouse pointer paradigm was used, and the results showed that external warning cues increased forward displacement. Experiment 2 indicated that the effects of phasic alertness and speed of motion on representational momentum were independent. In experiment 3, the probe paradigm was used, and the results showed that external warning cues increased forward displacement as well as participants’ sensitivity to the difference between the target and probe positions. These findings prove that phasic alertness boosts rather than reduces representational momentum. We propose that phasic alertness might influence representational momentum by modulating the process of executive control in the retention interval.

Prediction, Suppression of Visual Response, and Modulation of Visual Perception: Insights From Visual Evoked Potentials and Representational Momentum

When a visual object changes its position along with certain sequential regularities, the visual system rapidly and automatically forms a prediction regarding the future position of the object based on the regularities. Such prediction can drastically alter visual perception. A phenomenon called representational momentum (RM: a predictive displacement of the perceived final position of a visual object along its recent regular pattern) has provided extensive evidence for the predictive modulation of visual perception. The purpose of the present study was to identify neural effects that could explain individual differences in the strength of the predictive modulation of visual perception as measured by RM. For this purpose, in two experiments with a conventional RM paradigm where a bar was discretely presented in a regular rotation manner (with a step of 18° in Experiment 1 and a step of 20° in Experiment 2), visual evoked potentials (VEPs) in response to the regularly rotated bar were measured, and correlations between the magnitudes of RM and VEPs were examined. The results showed that the magnitudes of RM and central P2 were negatively correlated, consistently in both experiments; participants who showed a smaller central P2 tended to exhibit greater RM. Together with a previous proposal that central P2 would represent delayed reactivation of lower visual areas around the striate and prestriate cortices via reentrant feedback projections from higher areas, the present results suggest that greater suppression of delayed reactivation of lower visual areas (as indicated by smaller central P2) may underlie stronger predictive modulation of visual perception (as indicated by greater RM).

Visual mismatch negativity and representational momentum: Their possible involvement in the same automatic prediction

To maintain real-time interaction with a dynamically changing visual object, the brain is thought to automatically predict the next state of the object based on the pattern of its preceding changes. A behavioral phenomenon known as representational momentum (RM: forward displacement of the remembered final state of an object along its preceding change pattern) and an electrophysiological phenomenon known as visual mismatch negativity (VMMN: an event-related brain potential component that is elicited when an object suddenly deviates from its preceding change pattern) have each indicated the existence of such automatic predictive processes. However, there has been no direct investigation of whether or not these phenomena are involved in the same predictive processes. To address this issue, the present study examined the correlation between RM and VMMN by using a hybrid paradigm in which both phenomena can be measured for the rotation of a bar. The results showed that the magnitudes of RM and VMMN were positively correlated; participants who exhibited greater RM along the regular rotation of a bar tended to show greater VMMN in response to sudden reversal embedded in the regular rotation of a bar. This result provides empirical support for the hypothesis that RM and VMMN may be involved in the same automatic predictive processes. Due to the methodological limitations of a correlation analysis, this hypothesis has to be carefully tested in future studies that examine the relationship between RM and VMMN from multiple perspectives.

Toward a general theory of momentum-like effects

The future actions, behaviors, and outcomes of objects, individuals, and processes can often be anticipated, and some of these anticipations have been hypothesized to result from momentum-like effects. Five types of momentum-like effects (representational momentum, operational momentum, attentional momentum, behavioral momentum, psychological momentum) are briefly described. Potential similarities involving properties of momentum-like effects (continuation, coherence, role of chance or guessing, role of sensory processing, imperviousness to practice or error feedback, shifts in memory for position, effects of changes in velocity, rapid occurrence, effects of retention interval, attachment to an object rather than an abstract frame of reference, nonrigid transformation) are described, and potential constraints on a future theory of momentum-like effects (dynamic representation, nature of extrapolation, sensitivity to environmental contingencies, bridging gaps between stimulus and response, increasing adaptiveness to the environment, serving as a heuristic for perception and action, insensitivity to stimulus format, importance of subjective consequences, role of knowledge and belief, automaticity of occurrence, properties of functional architecture) are discussed. The similarity and ubiquity of momentum-like effects suggests such effects might result from a single or small number of mechanisms that operate over different dimensions, modalities, and time-scales and provide a fundamental adaptation for perception and action.

An effect of contrast and luminance on visual representational momentum for location

Effects of the contrast of target luminance and background luminance, and of the absolute level of target luminance, on representational momentum for the remembered final location of a previously viewed moving target were examined. Targets were high in contrast or luminance, decreasing in contrast or luminance, increasing in contrast or luminance, or low in contrast or luminance; the background was black or white. Representational momentum for target location was larger if targets were high or increasing in contrast or luminance and smaller if targets were low or decreasing in contrast or luminance. Representational momentum for target location was larger if targets were presented on a white background than on a black background. Implications for theories of localization and for theories of representational momentum are discussed.

Displacement of location in illusory line motion

Six experiments examined displacement in memory for the location of the line in illusory line motion (ILM; appearance or disappearance of a stationary cue is followed by appearance of a stationary line that is presented all at once, but the stationary line is perceived to "unfold" or "be drawn" from the end closest to the cue to the end most distant from the cue). If ILM was induced by having a single cue appear, then memory for the location of the line was displaced toward the cue, and displacement was larger if the line was closer to the cue. If ILM was induced by having one of two previously visible cues vanish, then memory for the location of the line was displaced away from the cue that vanished. In general, the magnitude of displacement increased and then decreased as retention interval increased from 50 to 250 ms and from 250 to 450 ms, respectively. Displacement of the line (a) is consistent with a combination of a spatial averaging of the locations of the cue and the line with a relatively weaker dynamic in the direction of illusory motion, (b) might be implemented in a spreading activation network similar to networks previously suggested to implement displacement resulting from implied or apparent motion, and (c) provides constraints and challenges for theories of ILM.

Representational momentum in older adults

Humans have a tendency to perceive motion even in static images that simply "imply" movement. This tendency is so strong that our memory for actions depicted in static images is distorted in the direction of implied motion - a phenomenon known as representational momentum (RM). In the present study, we created an RM display depicting a pattern of implied (clockwise) rotation of a rectangle. Young adults viewers' memory of the final position of the test rectangle was biased in the direction of continuing rotation, but older adults did not show a similar memory bias. We discuss several possible explanations for this group difference, but argue that the failure of older adults to shown an RM effect most likely reflects age-related changes in areas of the brain involved in processing real and implied motion.

Cross-modal influences on representational momentum and representational gravity

Effects of cross-modal information on representational momentum and on representational gravity (ie on displacement of remembered location in the direction of target motion or in the direction of gravitational attraction, respectively) were examined. In experiment 1, ascending or descending visual motion (in the picture plane) was paired with ascending or descending auditory motion (in frequency space); motion was congruent (both ascending, both descending) or incongruent (one ascending, one descending). Memory for visual location or auditory pitch was probed. Congruence resulted in larger forward displacement for auditory pitch, but did not influence forward displacement for visual location. In experiment 2, horizontal visual motion was paired with ascending, descending, or no auditory motion. Memory for visual location was displaced downward with descending or no auditory motion, and downward displacement was larger for visual motion paired with descending auditory motion than for visual motion paired with ascending auditory motion. Effects of cross-modal information on displacement suggest representational momentum and representational gravity reflect high-level processing.

Comment and Reply Why eye movements and perceptual factors have to be controlled in studies on “representational momentum”

In order to study memory of the final position of a smoothly moving target, Hubbard (e.g., Hubbard and Bharucha, 1988) presented smooth stimulus motion and used motor responses. In contrast, Freyd (e.g., Freyd and Finke, 1984) presented implied stimulus motion and used the method of constant stimuli. The same forward error was observed in both paradigms. However, the processes underlying the error may be very different. When smooth stimulus motion is followed by smooth pursuit eye movements, the forward error is associated with asynchronous processing of retinal and extraretinal information. In the absence of eye movements, no forward displacement is observed with smooth motion. In contrast, implied motion produces a forward error even without eye movements, suggesting that observers extrapolate the next target step when successive target presentations are far apart. Finally, motor responses produce errors that are not observed with perceptual judgments, indicating that the motor system may compensate for neuronal latencies.

Representational momentum and related displacements in spatial memory: A review of the findings

Memory for the final location of a moving target is often displaced in the direction of target motion, and this has been referred to as representational momentum. Characteristics of the target (e.g., velocity, size, direction, and identity), display (e.g., target format, retention interval, and response method), context (landmarks, expectations, and attribution of motion source), and observer (e.g., allocation of attention, eye movements, and psychopathology) that influence the direction and magnitude of displacement are reviewed. Specific conclusions regarding numerous variables that influence displacement (e.g., presence of landmarks or surrounding context), as well as broad-based conclusions regarding displacement in general (e.g., displacement does not reflect objective physical principles, may reflect aspects of naive physics, does not solely reflect eye movements, may involve some modular processing, and reflects high-level processes) are drawn. A possible computational theory of displacement is suggested in which displacement (1) helps bridge the gap between perception and action and (2) plays a critical part in localizing stimuli in the environment.

Illusory motion and representational momentum

When a moving target vanishes abruptly, participants judge its final position as being ahead of its actual final position, in the direction of motion (representational momentum; Freyd & Finke, 1984). In the present study, we presented illusory motion and examined whether or not forward displacement was affected by the perceived direction and speed of the target. Experiments 1A and 1B showed that an illusory direction of movement of a target was perceived, and Experiment 2 showed that an illusory speed of a moving target was observed. However, neither the direction nor the magnitude of forward displacement was affected by these illusions. Therefore, it was suggested that the mechanism underlying forward displacement (or some extrapolation processing) uses different motion signals than does the perceptual mechanism.