Motor processes in mental rotation

Much indirect evidence supports the hypothesis that transformations of mental images are at least in part guided by motor processes, even in the case of images of abstract objects rather than of body parts. For example, rotation may be guided by processes that also prime one to see results of a specific motor action. We directly test the hypothesis by means of a dual-task paradigm in which subjects perform the Cooper-Shepard mental rotation task while executing an unseen motor rotation in a given direction and at a previously learned speed. Four results support the inference that mental rotation relies on motor processes. First, motor rotation that is compatible with mental rotation results in faster times and fewer errors in the imagery task than when the two rotations are incompatible. Second, the angle through which subjects rotate their mental images, and the angle through which they rotate a joystick handle are correlated, but only if the directions of the two rotations are compatible. Third, motor rotation modifies the classical inverted V-shaped mental rotation response time function, favoring the direction of the motor rotation; indeed, in some cases motor rotation even shifts the location of the minimum of this curve in the direction of the motor rotation. Fourth, the preceding effect is sensitive not only to the direction of the motor rotation, but also to the motor speed. A change in the speed of motor rotation can correspondingly slow down or speed up the mental rotation

On Cognitive Neuroscience

Stephen M. Kosslyn is Professor of Psychology at Harvard University and an Associate Psychologist in the Department of Neurology at the Massachusetts General Hospital. He received his B.A. in 1970 from UCLA and his Ph.D. from Stanford University in 1974, both in psychology, and taught at Johns Hopkins, Harvard, and Brandeis Universities before joining the Harvard Faculty as Professor of Psychology in 1983. His work focuses on the nature of visual mental imagery and high-level vision, as well as applications of psychological principles to visual display design. He has published over 125 papers on these topics, co-edited five books, and authored or co-authored five books. His books include Image and Mind (1980), Ghosts in the Mind's Machine (1983), Wet Mind: The New Cognitive Neuroscience (with 0. Koenig, 1992), Elements of Graph Design (1994), and Image and Brain: The Resolution of the Imagery Debate (1994). Dr. Kosslyn has received numerous honors, including the National Academy of Sciences Initiatives in Research Award, is currently on the editorial boards of many professional journals, and has served on several National Research Council committees to advise the government on new technologies.Psycholog

Reading the mind's eye: Decoding category information during mental imagery

Category information for visually presented objects can be read out from multi-voxel patterns of fMRI activity in ventral–temporal cortex. What is the nature and reliability of these patterns in the absence of any bottom–up visual input, for example, during visual imagery? Here, we first ask how well category information can be decoded for imagined objects and then compare the representations evoked during imagery and actual viewing. In an fMRI study, four object categories (food, tools, faces, buildings) were either visually presented to subjects, or imagined by them. Using pattern classification techniques, we could reliably decode category information (including for non-special categories, i.e., food and tools) from ventral–temporal cortex in both conditions, but only during actual viewing from retinotopic areas. Interestingly, in temporal cortex when the classifier was trained on the viewed condition and tested on the imagery condition, or vice versa, classification performance was comparable to within the imagery condition. The above results held even when we did not use information in the specialized category-selective areas. Thus, the patterns of representation during imagery and actual viewing are in fact surprisingly similar to each other. Consistent with this observation, the maps of “diagnostic voxels” (i.e., the classifier weights) for the perception and imagery classifiers were more similar in ventral–temporal cortex than in retinotopic cortex. These results suggest that in the absence of any bottom–up input, cortical back projections can selectively re-activate specific patterns of neural activity

Visual Mental Imagery and Visual Perception: Structural Equivalence Revealed by Scanning Processes

The research reported in the present article investigates whether information is represented the same way in both visual mental imagery and the early phases of visual perception. In Experiment 1, the same participants scanned over patterns of dots in a mental image (with images based on a just-seen pattern), during perception, and in an iconic image. The time to scan increasing distances increased at comparable rates in the three tasks. However, in Experiment 2, when mental images were created from information stored in long-term memory, participants scanned more slowly in the mental image condition. Nevertheless, the rates of scanning in the perceptual tasks were highly correlated with the rates of scanning in the imagery tasks in both experiments. The results provide evidence that mental images and perceived stimuli are represented similarly and can be processed in the same way.Psycholog

Imagining Predictions: Mental Imagery as Mental Emulation

We argue that the primary function of mental imagery is to allow us to generate specific predictions based upon past experience. All imagery allows us to answer 'what if ' questions by making explicit and accessible the likely consequences of being in a specific situation or performing a specific action. Imagery is also characterized by its reliance on perceptual representations and activation of perceptual brain systems. We use this conception of imagery to argue that all imagery is simulation more specifically, it is a specific type of simulation in which the mental processes that 'run' the simulation emulate those that would actually operate in the simulated scenario. This type of simulation, which we label emulation, has benefits over other types of simulations that merely mimic the content of the simulated scenario.Psycholog

On Picturing a Candle: The Prehistory of Imagery Science

The past 25 years have seen a rapid growth of knowledge about brain mechanisms involved in visual mental imagery. These advances have largely been made independently of the long history of philosophical – and even psychological – reckoning with imagery and its parent concept ‘imagination’. We suggest that the view from these empirical findings can be widened by an appreciation of imagination’s intellectual history, and we seek to show how that history both created the conditions for – and presents challenges to – the scientific endeavor. We focus on the neuroscientific literature’s most commonly used task – imagining a concrete object – and, after sketching what is known of the neurobiological mechanisms involved, we examine the same basic act of imagining from the perspective of several key positions in the history of philosophy and psychology. We present positions that, firstly, contextualize and inform the neuroscientific account, and secondly, pose conceptual and methodological challenges to the scientific analysis of imagery. We conclude by reflecting on the intellectual history of visualization in the light of contemporary science, and the extent to which such science may resolve long-standing theoretical debates

Fear Selectively Modulates Visual Mental Imagery and Visual Perception

Emotions have been shown to modulate low-level visual processing of simple stimuli. In this study, we investigate whether emotions only modulate processing of visual representations created from direct visual inputs or whether they also modulate representations that underlie visual mental images. Our results demonstrate that when participants visualize or look at the global shape of written words (low-spatial-frequency visual information), the prior brief presentation of fearful faces enhances processing, whereas when participants visualize or look at details of written words (high-spatial-frequency visual information), the prior brief presentation of fearful faces impairs processing. This study demonstrates that emotions have similar effects on low-level processing of visual percepts and of internal representations created on the basis of information stored in long-term memory.Psycholog

Expert interpretation of bar and line graphs: The role of graphicacy in reducing the effect of graph format.

The distinction between informational and computational equivalence of representations, first articulated by Larkin and Simon (1987) has been a fundamental principle in the analysis of diagrammatic reasoning which has been supported empirically on numerous occasions. We present an experiment that investigates this principle in relation to the performance of expert graph users of 2 × 2 'interaction' bar and line graphs. The study sought to determine whether expert interpretation is affected by graph format in the same way that novice interpretations are. The findings revealed that, unlike novices—and contrary to the assumptions of several graph comprehension models—experts' performance was the same for both graph formats, with their interpretation of bar graphs being no worse than that for line graphs. We discuss the implications of the study for guidelines for presenting such data and for models of expert graph comprehension

Crime Alert! How Thinking about a Single Suspect Automatically Shifts Stereotypes toward an Entire Group

Crime alerts are meant to raise community awareness and identify individual criminal suspects; they are not expected to affect attitudes and beliefs toward the social group to which an individual suspect belongs. However, psychological principles of learning, categorization, and memory predict that what is learned about an instance can color perception of an entire category. At the intersection of psychology, criminal justice, sociology, and media studies, two experiments were conducted to test the effect that providing individual racial identity in crime alerts has on racial group stereotypes. In Experiment 1, participants visualized four scenarios involving Black or White would-be criminals. Results revealed that in the case where Black would-be criminals were made salient in memory, participants demonstrated significantly more negative implicit stereotypes toward Blacks as a group compared with a condition in which White would-be criminals were more salient in memory. In Experiment 2, participants read a written description of a crime scene with a suspect who was either depicted as White or Black, and then imagined the suspect. On both implicit and explicit measures of group stereotypes obtained afterward, participants who read about a Black criminal reported and revealed more anti-Black/pro-White stereotypes than did those who read about a White criminal. Crime alerts that mention racial identity, whatever their benefit, come with the burden of shifting stereotypes of social groups. In this context, the value of racial identification in crime alerts warrants reconsideration.Psycholog

Visual mental imagery during caloric vestibular stimulation.

We investigated high-resolution mental imagery and mental rotation, while the participants received caloric vestibular stimulation. High-resolution visual mental imagery tasks have been shown to activate early visual cortex, which is deactivated by vestibular input. Thus, wepredicted that vestibular stimulation would disrupt high-resolution mental imagery; this prediction was confirmed. In addition, mental rotationtasks have been shown to activate posterior parietal cortex, which is also engaged in the processing of vestibular stimulation. As predicted,we also found that mental rotation is impaired during vestibular stimulation. In contrast, such stimulation did not affect performance of alow-imagery control task. These data document previously unsuspected interactions between the vestibular system and the high-level visualsystem