Beyond visual imagery: How modality-specific is enhanced mental imagery in synesthesia?

Synesthesia based in visual modalities has been associated with reports of vivid visual imagery. We extend this finding to consider whether other forms of synesthesia are also associated with enhanced imagery, and whether this enhancement reflects the modality of synesthesia. We used self-report imagery measures across multiple sensory modalities, comparing synesthetes’ responses (with a variety of forms of synesthesia) to those of non-synesthete matched controls. Synesthetes reported higher levels of visual, auditory, gustatory, olfactory and tactile imagery and a greater level of imagery use. Furthermore, their reported enhanced imagery is restricted to the modalities involved in the individual’s synesthesia. There was also a relationship between the number of forms of synesthesia an individual has, and the reported vividness of their imagery, highlighting the need for future research to consider the impact of multiple forms of synesthesia. We also recommend the use of behavioral measures to validate these self-report findings.     

Revision: is visual perception a requisite for visual imagery?

Vision is the most highly developed sense in man and represents the doorway through which most of our knowledge of the external world arises. Visual imagery can be defined as the representation of perceptual information in the absence of visual input. Visual imagery has been shown to complement vision in this acquisition of knowledge--it is used in memory retrieval, problem solving, and the recognition of properties of objects. The processes underlying visual imagery have been assimilated to those of the visual system and are believed to share a neural substrate. However, results from studies in congenitally and cortically blind subjects have opposed this hypothesis. Here I review the currently available evidence.     

Why is information displaced from visual working memory during visual search?

Research has shown that performing visual search while maintaining representations in visual working memory displaces up to one object's worth of information from memory. This memory displacement has previously been attributed to a nonspecific disruption of the memory representation by the mere presentation of the visual search array, and the goal of the present study was to determine whether it instead reflects the use of visual working memory in the actual search process. The first hypothesis tested was that working memory displacement occurs because observers preemptively discard about an object's worth of information from visual working memory in anticipation of performing visual search. Second, we tested the hypothesis that on target absent trials no information is displaced from visual working memory because no target is entered into memory when search is completed. Finally, we tested whether visual working memory displacement is due to the need to select a response to the search array. The findings rule out these alternative explanations. The present study supports the hypothesis that change-detection performance is impaired when a search array appears during the retention interval due to nonspecific disruption or masking.     

When is the ball going to hit the ground? Duration estimates, eye movements, and mental imagery of object motion

Performance in 2 versions of a computer-animated task was compared. Participants either indicated the time of arrival of a target that rolled off a horizontal surface and fell--hidden from view--onto a landing point (production task) or judged flight time on a rating scale (judgment task). As predicted, performance was significantly better in the production task (Experiment 1), in which imagery of object motion probably replaced reasoning processes. Participants who exhibited eye movements suggesting mental tracking performed particularly well in the production task (Experiment 2). There was, however, no decrement in performance when participants were asked to fixate the point where the target disappeared. For motion duration estimations, eye movements seem to be only a by-product of mental tracking.     

When does action resist visual illusions?

Over the past decade, many studies of non-pathological individuals have reported functional dissociations between perceptual judgments and motor responses. These results suggested an interpretation of the ventral and dorsal streams in the primate visual system as independent modules for visual awareness and the visual guidance of actions. However, recent comparisons of perception and grasping responses in size-contrast displays have been widely reported to show that apparent dissociations are actually experimental artifacts. An overview of the literature suggests that the issue of visuomotor dissociations in healthy individuals is far from settled. Some results suggest that immunity from visual illusions might be found when task requirements emphasize observer-relative reference frames. These results suggest that the functional specialization of the two visual subsystems might be less rigid than originally posited.     

When is Death Bad,When it is Bad?

Philosophia - On a view most secularists accept, the deceased individual goes out of existence. How, then, can death be a bad thing for, or harm, the deceased? I consider the doctrine of...     

What is wrong with imagery questionnaires?

Research evidence is reviewed which shows that the questionnaire method represents a deviant case in imagery research: Whereas experimental techniques consistently produce strong effects for the imagery variable in a large specter of cognitive tasks, research based on imagery questionnaires yields ambiguous and most frequently negative results. Existing explanations of the discrepant findings are critically examined and found to be inadequate. An alternative interpretation is offered, where it is hypothesized that the questionnaire approach to the study of imagery is infected by a serious methodological flaw, due to differences in subjective conceptions of the rating scale employed in imagery questionnaires. Experimental evidence is reported which supports this interpretation.     

Is there "feedback" during visual imagery? Evidence from a specificity of practice paradigm.

The specificity of practice hypothesis predicts the development of a sensorimotor representation specific to the afferent feedback available during skill acquisition (Proteau, 1992; Proteau, Marteniuk, Girouard, & Dugas, 1987). In the present investigation, we used the specificity of practice hypothesis to test whether skill acquisition through visual imagery would lead to the development of a sensory-specific movement representation similar to one resulting from actual practice. To accomplish this objective, participants practiced walking a 12-m linear path in one of three practice conditions, full-vision (FV), no-vision (NV), or visual imagery (VI), for either 10 or 100 trials. Knowledge of spatial and/or temporal results (KR) was provided to participants following each trial during this phase. Following acquisition, participants completed 10 NV trials without KR. An analysis of root-mean-squared-error (RMSE) indicated NV participants were more accurate than both FV and VI participants in the transfer condition. We believe the equivalence in transfer RMSE between FV and VI suggests that there are similarities between the movement representations attained by FV and VI practice.     

When is a picture?

Philosophical discussions of depiction sometimes suffer from a lack of differentiation between several questions concerning the ‘nature’ of pictorial representation. To provide a suitable framework I distinguish six such questions and several levels on which one might want to proceed in order to answer some of them. With this background, I reconstruct Goodman's and Elgin's answer to the specific question: ‘What distinguishes the pictorial from the verbal or linguistic?’ I try to reveal some major motivations behind their system-oriented approach and to indicate some reasons why a strategy of this kind is to a certain extent mandatory to grasp the ‘nature of the pictorial’. The system-relative and functional character of depiction has to be captured by every adequate theory.     

When is motion 'motion'?

Examples of visual motion have become more and more abstract over the years, leading up to 'third-order' stimuli where direction is actually determined by the observer through top - down attention. But how far can this be pushed--are there motion stimuli that are yet more arbitrary and abstract? Actually, there is a broad class of 'conceptual motion' stimuli--things like a moving grating of faces, or a shifting pattern of words--that are perfect analogs to traditional 'perceptual motion' stimuli, solvable by the same motion computation and for which observers can readily make direction-of-motion judgments. Interestingly though, these do not produce a sensation of motion (among other automatic consequences of motion detection). Here we compare a luminance-based perceptual motion stimulus to a semantic-based conceptual motion stimulus to contrast the psychophysical hallmarks of these motion categories.     

Inspecting visual mental images: Can people “see” implicit properties as easily in imagery and perception?

Can people “see” previously unnoticed properties in objects that they visualize, or are they locked into the organization of the pattern that was encoded during perception? To answer this question, we first asked a group to describe letters of the alphabet and found that some properties (such as the presence of a diagonal line) are often mentioned, whereas others (such as symmetry) are rarely if ever mentioned. Then we showed not only that other participants could correctly detect both kinds of properties in visualized letters, but also that the relative differences in the ease of detecting these two types of properties are highly similar in perception (when the letters are actually visible) and imagery (when the letters are merely visualized). These findings provide support for the view that images can be reinterpreted in ways much like what occurs during perception and speak to the wider issue of the long-standing debate about the format of mental images.     

Where is here? When is now?1

With a Kleinian perspective influenced by Betty Joseph, the author describes the distinctive ‘here and now’ of a psychoanalysis as the place and the time of the patient’s inner subjective world as it emerges in the work of patient and analyst. This psychoanalytic ‘here’ and ‘now’ is examined with clinical material from the analysis of Mr X; first, with an account of the way his analysis begins and then through a detailed session five years later.The author identifies Mr X’s problems with place and time, and how these change over the course of the analysis. He moves from sequestered dyadic relationships towards an Oedipal and family space, and from disconnection and timelessness to acquiring a sense of duration, of being in the present with a past and a future – all of which, the paper aims to show, has implications for technique.     

What is primed in priming from imagery?

Priming from imagery is typically weaker than that from perception. This has been interpreted as resulting from weaker activation of perceptual processes. However, for imagery and perception, commonality is only half the story: Each is also characterized by specific processes. If priming can be due to both unshared and shared components of imagery and perception, then it should be possible to observe greater priming from imagery than from perception. Two new priming experiments were designed to test this hypothesis, while controlling incidental task differences. In both experiments, participants studied objects by counting their parts (from a mental image or a picture). Experiment 1 used a word-picture matching test task, which was hypothesized to depend on stimulus processing specific to perception, and Experiment 2 a size judgment test task, which was hypothesized to depend on retrieval and generation processes specific to imagery. As predicted, priming for perceived objects was greater than priming for imagined objects in the word-picture matching task. Conversely, in the size judgment task, more priming from imagery than from perception was observed. These results support the conclusions that (a) imagery and perception have substantial unshared processes, and (b) these processes contribute to priming.     

Is there a "special relationship" between unconscious emotions and visual imagery? Evidence from a mental rotation test

There is an increasing interest in the relationship between imagery and emotion (e.g., Holmes & Mathews, 2005). The present research examined whether unconscious emotions affect visual imagery. In particular, participants were invited to perform a mental rotation test following subliminal presentation of happy, sad and neutral expressions. This study revealed an increase in mental rotation abilities after unconscious visual processing of emotional expressions. Altogether, these findings support the hypothesis of a bidirectional relationship between imagery and emotions.     

Does threatening imagery sensitize distress during contaminant exposure?

Prominent models of fear focus on the role of cognition in the development and maintenance of maladaptive responses. Little research, however, has evaluated the impact of cognition on distress reduction. The current study uses an experimental design to examine the effect of different types of imagery (moving harm, static harm, and safety) on reduction of distress associated with a contaminating stimulus in a normal university sample. Results indicate that use of moving harm imagery sensitizes distress during a 30-min exposure, whereas static harm and safety imagery reduce distress. These findings demonstrate that cognitive factors can moderate affective response during exposure. Clinical implications for the treatment of anxiety disorders are discussed.     

How implicit is visual statistical learning?

In visual statistical learning, participants learn the statistical regularities present in a sequence of visual shapes. A recent study (Kim, Seitz, Feenstra, & Shams, 2009) suggests that visual statistical learning occurs implicitly, as it is not accompanied by conscious awareness of these regularities. However, that interpretation of the data depends on 2 unwarranted assumptions concerning the nature and sensitivity of the tasks used to measure learning. In a replication of this study, we used a 4-choice completion task as a direct measure of learning, in addition to an indirect measure consisting of a rapid serial visual presentation task. Moreover, binary confidence judgments were recorded after each completion trial. This way, we measured systematically the extent to which sequence knowledge was available to consciousness. Supporting the notion that the role of unconscious knowledge was overestimated in Kim et al.'s study, our results reveal that participants' performance cannot be exclusively accounted for by implicit knowledge. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

When is a Deleuzian becoming ?

Much has been written recently about the Deleuzian concept of becoming. Most of that writing, especially in feminist criticism, has drawn from the later collaborations with Guattari. However, the concept of a becoming arises earlier and appears more consistently across the trajectory of Deleuze's work than the discussion of specific becomings might lead one to believe. In this paper, I trace the concept of becoming in Deleuze's work, and specifically in the earlier works. By doing so, I hope to shed some light on the specific becomings that are the focus of the collaborative work with Guattari, and to deepen an understanding of the concept in general.