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.

An outstanding challenge for consciousness research is to characterize the neural signature of conscious access independently of any decisional processes. Here we present a model-based approach that uses inter-trial variability to identify the brain dynamics associated with stimulus processing. We demonstrate that, even in the absence of any task or behavior, the electroencephalographic response to auditory stimuli shows bifurcation dynamics around 250–300 milliseconds post-stimulus. Namely, the same stimulus gives rise to late sustained activity on some trials, and not on others. This late neural activity is predictive of task-related reports, and also of reports of conscious contents that are randomly sampled during task-free listening. Source localization further suggests that task-free conscious access recruits the same neural networks as those associated with explicit report, except for frontal executive components. Studying brain dynamics through variability could thus play a key role for identifying the core signatures of conscious access, independent of report.

Perceptual aftereffects provide a sensitive tool to investigate the influence of eye and head position on visual processing. There have been recent indications that the TAE is remapped around the time of a saccade to remain aligned to the adapting location in the world. Here, we investigate the spatial frame of reference of the TAE by independently manipulating retinal position, gaze orientation, and head orientation between adaptation and test. The results show that the critical factor in the TAE is the correspondence between the adaptation and test locations in a retinotopic frame of reference, whereas world- and head-centric frames of reference do not play a significant role. Our results confirm that adaptation to orientation takes place at retinotopic levels of visual processing. We suggest that the remapping process that plays a role in visual stability does not transfer feature gain information around the time of eye (or head) movements.

Examines the who, what and why of the knowledge mapping process used in the visual display of information in contemporary organizations. Knowledge mapping serves as the continuously evolving organizational memory, capturing and integrating strategic explicit knowledge within an organization and between an organization and its external environment. Knowledge map making is treated as a medium of communication over what is important and actionable information (knowledge) in organizational contexts. Effective knowledge maps take into account the who, what and why of the knowledge mapping process. Effective knowledge maps help identify intellectual capital, socialize new members, enhance organizational learning and help anticipate impending threats and/or opportunities.

One of the ways that we perceive shape is through seeing motion. Visual motion may be actively generated (for example, in locomotion), or passively observed. In the study of the perception of three-dimensional structure from motion, the non-moving, passive observer in an environment of moving rigid objects has been used as a substitute for an active observer moving in an environment of stationary objects; this 'rigidity hypothesis' has played a central role in computational and experimental studies of structure from motion. Here we show that this is not an adequate substitution because active and passive observers can perceive three-dimensional structure differently, despite experiencing the same visual stimulus: active observers' perception of three-dimensional structure depends on extraretinal information about their own movements. The visual system thus treats objects that are stationary (in an allocentric, earth-fixed reference frame) differently from objects that are merely rigid. These results show that action makes an important contribution to depth perception, and argue for a revision of the rigidity hypothesis to incorporate the special case of stationary objects.

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Purpose -The purpose of this paper is to examine the manner in which advocates of crowdsourcing reconfigure the classical sociological treatment of the crowd. Design/methodology/approach -The approach taken conceives of the semantics of crowd theorizing in three phases, each of which makes sense of the power dynamics between the elite and the crowd. In phases one and two, the crowd is conceptualized as a problem generator; in phase three, the crowd is depicted as a problem solver and innovator. Findings -This paper provides a critical look at phase three crowd theorizing. It explores how, by ignoring the disruptive power dynamic, crowdsourcing generates a credible image of the crowd as an innovator and problem solver. The work concludes with a discussion of the implications of phase three crowd theorizing for researchers in sociology. Practical implications -Advocates of the wisdom of crowds, if interested in the sociological implications of their position, must attend to both the disruptive and costly implications of third phase crowd theorizing. Originality/value -This paper maps the crowdsourcing process and places it in context. It argues that the distance between the classical social scientific treatment of the crowd is not nearly as great as crowdsourcing advocates would have one believe. Nevertheless, phase three crowd theorizing opens up sociologically relevant questions regarding the future portrayal of collective intelligence as a form of virtual property.

Studies of perception usually emphasize processes that are largely universal across observers and-except for short-term fluctuationsstationary over time. Here we test the universality and stationarity assumptions with two families of ambiguous visual stimuli. Each stimulus can be perceived in two different ways, parameterized by two opposite directions from a continuous circular variable. A large-sample study showed that almost all observers have preferred directions or biases, with directions lying within 90 degrees of the bias direction nearly always perceived and opposite directions almost never perceived. The biases differ dramatically from one observer to the next, and although nearly every bias direction occurs in the population, the population distributions of the biases are nonuniform, featuring asymmetric peaks in the cardinal directions. The biases for the two families of stimuli are independent and have distinct population distributions. Following external perturbations and spontaneous fluctuations, the biases decay over tens of seconds toward their initial values. Persistent changes in the biases are found on time scales of several minutes to 1 hour. On scales of days to months, the biases undergo a variety of dynamical processes such as drifts, jumps, and oscillations. The global statistics of a majority of these long-term time series are well modeled as random walk processes. The measurable fluctuations of these hitherto unknown degrees of freedom show that the assumptions of universality and stationarity in perception may be unwarranted and that models of perception must include both directly observable variables as well as covert, persistent states.T he neural networks underlying visual perception are complex systems and, as such, undoubtedly have internal states. The formal notion of "state" can be defined as the minimal set of variables that, together with the input to a system and the fixed processing mechanisms, allows one to predict the system's output (1). If perception is a function of both the sensory input and internal states, then-because states can vary both across individual observers and over time-the presence of an internal state would manifest itself as potentially large individual differences in the perception of the same stimulus and in coherent temporal variations of perception of the same stimulus over time in a single observer. It is known that visual functions can be modulated (2) on brief time scales by priming (3-6), aftereffects (7-9), and sequence effects (10-13) [and sometimes on larger time scales as well (14)]; can undergo visible short-term fluctuations in the presence of multistable stimuli (15-20); and can undergo long-term or permanent changes in their structure through learning (21-24). Despite these examples, little is known about internal states of the visual system. In terms of underlying mechanisms, the internal state is represented naturally in recurrent but not in feed-forward neural networks (25, 26).Here we measure patterns of biases in two families of vis...