There is an increasing interest in the relationship between imagery and emotion . 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.

Traditionally, philosophers have appealed to the phenomenological similarity between visual experience and visual imagery to support the hypothesis that there is significant overlap between the perceptual and imaginative domains. The current evidence, however, is inconclusive: while evidence from transcranial brain stimulation seems to support this conclusion, neurophysiological evidence from brain lesion studies (e.g., from patients with brain lesions resulting in a loss of mental imagery but not a corresponding loss of perception and vice versa) indicates that (...) there are functional and anatomical dissociations between mental imagery and perception. Assuming that the mental imagery and perception do not overlap, at least, to the extent traditionally assumed, then the question arises as to what exactly mental imagery is and whether it parallels perception by proceeding via several functionally distinct mechanisms. In this review, we argue that even though there may not be a shared mechanism underlying vision for perception and conscious imagery, there is an overlap between the mechanisms underlying vision for action and unconscious visual imagery. On the basis of these findings, we propose a modification of Kosslyn’s model of imagery that accommodates unconscious imagination and explore possible explanations of the quasi-pictorial phenomenology of conscious visual imagery in light of the fact that its underlying neural substrates and mechanisms typically are distinct from those of visual experience. (shrink)

Jeannerod's target article describes support, through empirical and neurological findings, for the intriguing idea of motor imagery, a form of representation hypothesized to have levels of functional equivalence with motor preparation, while being consciously accessible. Jeannerod suggests that the subjectively accessible content of motor imagery allows it to be distinguished from motor preparation, which is unconscious. Motor imagery is distinguished from visual imagery in terms of content. Motor images are kinesthetic in nature; they are (...) parametrized by variables such as force and time and they are potentially governed by kinematic rules. Jeannerod acknowledges, however, that motor and visual imagery may not easily be separated, because actions take place in a spatial environment. I agree; in fact, I suggest here that visualization may generally be concomitant with, and may even subjectively dominate, motor imagery. (shrink)

(Open Access article, freely available to download from publisher's site.) Our visual experiences of objects as located in external space, and as having definite three-dimensional shapes, are closely linked to our implicit expectations about what things will look like from alternative viewpoints. What sorts of contents do these expectations involve? One standard answer is that they relate to what things will look like to us upon changing our positions. And what sorts of mental representations do the expectations call upon? (...) A standard answer is that they involve our powers of visual imagery; this answer requires us to allow for the possibility of unconscious visual imagery, however. The current paper presents an alternative model of the contents of our implicit visual expectations, one that regards them as wholly nonreflexive. It also argues that, once we ascribe the relevant contents to the expectations, there is no longer any reason for holding that they involve our powers of visual imagery. (shrink)

Jackendoff comes to some appealing overall conclusions, but several of his assumptions and arguments are questionable. The present commentary points out the following problems: oversimplifications in the translation-based argument for the independence of language and thought; a lack of consideration of the possibility of unconscious use of internalized natural languages; insufficient consideration of possible characteristics of languages of thought ; neglect of the possibility of thinking in example-oriented and metaphorical ways; unfair bias in contrasting visual to linguistic (...) class='Hi'>imagery; neglect of other types of imagery; and neglect of the possibility of unconscious attentional processes. (shrink)

The question of whether phenomenal consciousness is limited to the capacity of cognitive access remains a contentious issue in philosophy. Overflow theorists argue that the capacity of conscious experience outstrips the capacity of cognitive access. This paper demonstrates a resolution to the overflow debate is found in acknowledging a difference in phenomenological timing required by both sides. It makes clear that the “no overflow” view requires subjects to, at the bare minimum, generate an unconscious visual image of previously (...) presented items if it is to explain performance in the change detection paradigm. It then demonstrates that conscious imagery should support better task performance than unconscious imagery because of a necessary difference in representational strength. However, this contradicts empirical findings, and so a new argument for overflow is presented without requiring the premise that subjects need to obtain a specific phenomenology of presented items during change detection. (shrink)

Jackendoff comes to some appealing overall conclusions, but several of his assumptions and arguments are questionable. The present commentary points out the following problems: oversimplifications in the translation-based argument for the independence of language and thought; a lack of consideration of the possibility of unconscious use of internalized natural languages; insufficient consideration of possible characteristics of languages of thought ; neglect of the possibility of thinking in example-oriented and metaphorical ways; unfair bias in contrasting visual to linguistic (...) class='Hi'>imagery; neglect of other types of imagery; and neglect of the possibility of unconscious attentional processes. (shrink)

The overarching guiding principle of Alan Turing’s work was directed towards modelling the human mind as a machine. It is extraordinary that Turing introduced, in his early papers, ideas that are only now beginning to be investigated. Throughout his life, he considered conjectures to be of great importance because they suggest useful lines of research. In my own conjecture, I am asking the question: what is the brain’s geometry? Can it ever be unravelled, or does its complexity defy any form (...) of visual representation? Recent research reveals that the detailed workings of the brain take place in a ‘global workspace’, where conscious contents appear to be disseminated globally to a great multitude of networks throughout the brain that are unconscious. During conscious tasks, neurons contributing to the global workspace enter into a coherent activation pattern by being tightly connected through long axons. Is it possible, therefore, that my proposed geometric pattern (an Islamic latticework) can be envisaged as a useful means of interconnecting multiple long axons in a unified global workspace dedicated to conscious thought? I share and communicate my idea through a process that combines visual imagery with musical performance (i.e. visual music). It is a method that can assist in clarifying concepts that might otherwise remain elusive or esoteric. (shrink)

Historically, mental imagery has been defined as an experiential state - as something necessarily conscious. But most behavioural or neuroimaging experiments on mental imagery - including the most famous ones - don’t actually take the conscious experience of the subject into consideration. Further, recent research highlights that there are very few behavioural or neural differences between conscious and unconscious mental imagery. I argue that treating mental imagery as not necessarily conscious (as potentially unconscious) would (...) bring much needed explanatory unification to mental imagery research. It would also help us to reassess some of the recent aphantasia findings inasmuch as at least some subjects with aphantasia would be best described as having unconscious mental imagery. (shrink)

Simulation Theory says we need not rely exclusively on prepositional knowledge of other minds in order to explain the actions of others. Seeking to know what you will do, I imagine myself in your situation, and see what decision I come up with. I argue that this conception of simulation naturally generalizes: various bits of our mental machine can be run‘off‐line’, fulfilling functions other than those they were made for. In particular, I suggest that visual imagery results when (...) the visual system is run off‐line. I briefly review the empirical evidence and consider the philosophical implications, particularly concerning the mode of mental representation in imagery. (shrink)

The “Perky effect” is the interference of visual imagery with vision. Studies of this effect show that visual imagery has more than symbolic properties, but these properties differ both spatially (including “pictorially”) and temporally from those of vision. We therefore reject both the literal picture-in-the-head view and the entirely symbolic view.

I examined the proposition that there are psychological limits on what scientific problems can be solved, and that these limits may be based on a failure to be able to produce imagable, observation-based models for any possible solution, a position suggested by philosopher Colin McGinn in an argument attempting to prove that the mind-body problem is unsolvable. I examined another likely candidate for an unsolvable problem -- the ultimate origin of the universe (i.e., what might have preceded the Big Bang (...) or any other starting point; why there should be something rather than nothing) -- by exploring the reasoning of physicists about this problem and measuring visual imagery frequency and vividness, with the expectation that those who most believed the problem unsolvable would be more frequent/vivid imagers and therefore more affected by the apparent impossibility of producing an imagable solution. Eight physicists were interviewed and imagery frequency and vividness measurements performed using Cohen & Saslona's IDQ-IHS and Marks's VVIQ, respectively. All subjects considered the problem unsolvable within today's physics and all but one thought the problem still meaningful, though none were optimistic about a solution. The one subject who dismissed the problem had the lowest imagery frequency score, and there was also a significant rank order correlation (r = 0.83, p < .02) between degree of belief in problem unsolvability (extended to include viewing the problem as meaningful and not already solved) and a composite imagery frequency/vividness score, though the sample was too small to control for some possible confounding factors. (shrink)

Defining Imagery: Experience or Representation?
Historical Development of Ideas about Imagery
Subjective Individual Differences in Imagery Experience
Theories of Imagery, and their Implications for Consciousness
Picture theory
Description theory
Enactive theory.

Explanations of animal problem-solving often represent our choices as limited to two: first, we can explain the observed behavior as a product of trained responses to sensory stimuli, or second, we can explain it as due to the animal’s possession of general rules utilizing general concepts. My objective in this essay is to bring to life a third alternative, namely, an explanation in terms of imagistic cognition.The theory of imagistic cognition posits representations that locate objects in a multidimensional similarity space. (...) It proposes that an animal’s expectations can be explained on the basis of the similarity of novel objects to objects previously encountered.The animal can predict the behavior of the novel object by producing a mental movie of the novel object by morphing it into an object, the behavior of which has previously been observed. After criticizing the theory of concept abstraction, I will identify some of the key elements of imagistic cognition.Then I will attempt to illustrate the utility of this conception of cognition by using it to explain the combination of successes and failures observed in monkeys in tool- mediated retrieval tasks (Fujita et al. 2003; Fujita et al. 2011) and in great apes in trap tube and trap table experiments (Martin-Ordas et al. 2008; Martin-Ordas et al. 2012). (shrink)

It is clear that visual imagery is somehow significantly visual. Some theorists, like Kosslyn, claim that the visual nature of visualisations derives from features of the neural processes which underlie those episodes. Pylyshyn claims, however, that it may merely reflect special features of the contents which we grasp when we visualise things. This paper discusses and rejects Pylyshyn's own attempts to identify the respects in which the contents of visualisations are notably visual. It then offers (...) a novel and very different account of what is distinctively sensory about the contents of sensory images. The paper's alternative account is used in explaining various pieces of phenomenological and behavioural data concerning visualisation. Finally, it is tentatively suggested that the proposed account of the contents of sensory images may also shed light upon some of the neurological data involving visualisation and sensory imagery more generally. (shrink)

Visual imagery is a form of sensory imagination, involving subjective experiences typically described as similar to perception, but which occur in the absence of corresponding external stimuli. We used the Activation Likelihood Estimation algorithm (ALE) to identify regions consistently activated by visual imagery across 40 neuroimaging studies, the first such meta-analysis. We also employed a recently developed multi-modal parcellation of the human brain to attribute stereotactic co-ordinates to one of 180 anatomical regions, the first time this (...) approach has been combined with the ALE algorithm. We identified a total 634 foci, based on measurements from 464 participants. Our overall comparison identified activation in the superior parietal lobule, particularly in the left hemisphere, consistent with the proposed ‘top-down’ role for this brain region in imagery. Inferior premotor areas and the inferior frontal sulcus were reliably activated, a finding consistent with the prominent semantic demands made by many visual imagery tasks. We observed bilateral activation in several areas associated with the integration of eye movements and visual information, including the supplementary and cingulate eye fields (SCEFs) and the frontal eye fields (FEFs), suggesting that enactive processes are important in visual imagery. V1 was typically activated during visual imagery, even when participants have their eyes closed, consistent with influential depictive theories of visual imagery. Temporal lobe activation was restricted to area PH and regions of the fusiform gyrus, adjacent to the fusiform face complex (FFC). These results provide a secure foundation for future work to characterise in greater detail the functional contributions of specific areas to visual imagery. (shrink)

The McCollough effect, an orientation-contingent color aftereffect, has been known for over 30 years and, like other aftereffects, has been taken as a means of probing the brain's operations psychophysically. In this paper, we review psychophysical, neuropsychological, and neuroimaging studies of the McCollough effect. Much of the evidence suggests that the McCollough effect depends on neural mechanisms that are located early in the cortical visual pathways, probably in V1. We also review evidence showing that the aftereffect can be induced (...) without conscious perception of the induction patterns. Based on these two lines of evidence, it is argued that our conscious visual experience of the world arises in the cortical visual system beyond V1. (shrink)

Eye movements during mental imagery are not epiphenomenal but assist the process of image generation. Commands to the eyes for each fixation are stored along with the visual representation and are used as spatial index in a motor‐based coordinate system for the proper arrangement of parts of an image. In two experiments, subjects viewed an irregular checkerboard or color pictures of fish and were subsequently asked to form mental images of these stimuli while keeping their eyes open. During (...) the perceptual phase, a group of subjects was requested to maintain fixation onto the screen's center, whereas another group was free to inspect the stimuli. During the imagery phase, all of these subjects were free to move their eyes. A third group of subjects (in Experiment 2) was free to explore the pattern but was requested to maintain central fixation during imagery. For subjects free to explore the pattern, the percentage of time spent fixating a specific location during perception was highly correlated with the time spent on the same (empty) locations during imagery. The order of scanning of these locations during imagery was correlated to the original order during perception. The strength of relatedness of these scanpaths and the vividness of each image predicted performance accuracy. Subjects who fixed their gaze centrally during perception did the same spontaneously during imagery. Subjects free to explore during perception, but maintaining central fixation during imagery, showed decreased ability to recall the pattern. We conclude that the eye scanpaths during visual imagery reenact those of perception of the same visual scene and that they play a functional role. (shrink)

This paper describes an operational computer simulation of visual mental imagery in humans. The structure of the simulation was motivated by results of experiments on how people represent information in, and access information from, visual images. The simulation includes a “surface representation,” which is spatial and quasi‐pictorial, and an underlying “deep representation,” which contains “perceptual” information encoding appearance plus “propositional” information describing facts about an object. The simulation embodies a theory of how surface images are generated from (...) deep representations, and how surface images are processed when one accesses information embedded in them. The simulation also offers an account of various sorts of imagery transformations. (shrink)

Students of geometry do not prove Euclid's first theorem by examining an accompanying diagram, or by visualizing the construction of a figure. The original proof of Euclid's first theorem is incomplete, and this gap in logic is undetected by visual imagination. While cognition involves truth values, vision does not: the notions of inference and proof are foreign to vision.

The paper argues that the English verb ‘to see’ can denote three different kinds of conscious states of seeing, involving visual experiences, visual seeming states and introspective seeming states, respectively. The case for the claim that there are three kinds of seeing comes from synesthesia and visual imagery. Synesthesia is a relatively rare neurological condition in which stimulation in one sensory or cognitive stream involuntarily leads to associated experiences in a second unstimulated stream. Visual synesthesia (...) is often considered a case of illusory visual experience. This, however, turns out to be a questionable characterization, as there is evidence suggesting that the brain must cognitively process the stimulus in order for the associated synesthetic experience to arise. Furthermore, some very vivid, visual forms of synesthesia do not involve additional processing in the visual cortex. Visual synesthetic experience is likely to be a non-veridical state of seeming rather than an illusory visual experience. Visual seeming states are cognitive states distinct from visual experiences in terms of their representational richness and their neural correlates. Visual seeming states that are non-deviantly causally related to the states of affair they represent constitute a type of non-experiental seeing. Introspective seeming states that are non-deviantly causally related to underlying visual images constitute a second type of non-experiental seeing. The English verb ‘to see’ can denote all three types of seeing, which is to say that ‘to see’ is polysemous. (shrink)

Brain-computer interfaces are communication bridges between a human brain and external world, enabling humans to interact with their environment without muscle intervention. Their functionality, therefore, depends on both the BCI system and the cognitive capacities of the user. Motor-imagery BCIs rely on the users’ mental imagination of body movements. However, not all users have the ability to sufficiently modulate their brain activity for control of a MI-BCI; a problem known as BCI illiteracy or inefficiency. The underlying mechanism of this (...) phenomenon and the cause of such difference among users is yet not fully understood. In this study, we investigated the impact of several cognitive and psychological measures on MI-BCI performance. Fifty-five novice BCI-users participated in a left- versus right-hand motor imagery task. In addition to their BCI classification error rate and demographics, psychological measures including personality factors, affinity for technology, and motivation during the experiment, as well as cognitive measures including visuospatial memory and spatial ability and Vividness of Visual Imagery were collected. Factors that were found to have a significant impact on MI-BCI performance were Vividness of Visual Imagery, and the personality factors of orderliness and autonomy. These findings shed light on individual traits that lead to difficulty in BCI operation and hence can help with early prediction of inefficiency among users to optimize training for them. (shrink)

It has been claimed that the ability to remember the past and the ability to project oneself into the future are intimately related. We sought support for this proposition by examining whether individual differences in dimensions that have been shown to affect memory for past events similarly influence the experience of projecting oneself into the future. We found that individuals with a higher capacity for visual imagery experienced more visual and other sensory details both when remembering past (...) events and when imagining future events. In addition, individuals who habitually use suppression to regulate their emotions experienced fewer sensory, contextual, and emotional details when representing both past and future events, while the use of reappraisal had no effect on either kind of events. These findings are consistent with the view that mental time travel into the past and into the future relies on similar mechanisms. (shrink)

To test the notion that shifts in visual imagery and attention are correlated with experiences of emotion, we studied 10 dream reports using an affirmative probe of emotion and a quantitative measure of plot discontinuity. We found that emotion, especially changes in emotion, are correlated with discontinuities in visual imagery. These correlations are quantified using a new graph theoretical method for analyzing narrative reports.

It has been suggested that certain problems may be unsolvable because of the mind's cognitive structure, but we may wonder what problems, and exactly why. The ultimate origin of the universe and the mind-body problem seem to be two such problems. As to why, Colin McGinn has argued that the mind-body problem is unsolvable because any theoretical concepts about the brain will be observation-based and unable to connect to unobservable subjective experience. McGinn's argument suggests a requirement of imagability -- an (...) observation basis -- for physical causal explanation that cannot be met for either of these problems. Acausal descriptions may be possible but not the causal analyses that provide the greatest explanatory satisfaction, a psychological phenomenon that seems tied to the strength of the underlying observation basis but is affected by other factors as well. (shrink)

It has been claimed that the ability to remember the past and the ability to project oneself into the future are intimately related. We sought support for this proposition by examining whether individual differences in dimensions that have been shown to affect memory for past events similarly influence the experience of projecting oneself into the future. We found that individuals with a higher capacity for visual imagery experienced more visual and other sensory details both when remembering past (...) events and when imagining future events. In addition, individuals who habitually use suppression to regulate their emotions experienced fewer sensory, contextual, and emotional details when representing both past and future events, while the use of reappraisal had no effect on either kind of events. These findings are consistent with the view that mental time travel into the past and into the future relies on similar mechanisms. (shrink)

Observations on patients who lost visual imagery after brain damage call into question the notion that the knowledge subserving visual imagery is “tacit.” Dissociations between deficient imagery and preserved recognition of objects suggest that imagery is exclusively based on explicit knowledge, whereas retrieval of “tacit” visual knowledge is bound to the presence of the object and the task of recognizing it.