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This study investigated the potential for the development of novel perceptual experiences through sustained training with a sensory augmentation device. We developed (1) a new geomagnetic sensory augmentation device, the NaviEar, and (2) a battery of tests for automaticity in the use of the device. The NaviEar translates head direction toward north into continuous sound according to a “wind coding” principle. To facilitate automatization of use, its design is informed by considerations of the embodiment of spatial orientation and multi-sensory integration, and it uses a sensory coding scheme derived from means for auditory perception of wind direction that is common in sailing because it is easy to understand and use. The test battery assesses different effects of automaticity (interference, rigidity of responses, and dynamic integration) assuming that automaticity is a necessary criterion to show the emergence of perceptual feel, that is, an augmented experience with perceptual phenomenal quality. We measured performance in simple training tasks, administered the tests for automaticity, and assessed subjective reports through a questionnaire. Results suggest that the NaviEar is easy and comfortable to use and has a potential for applications in real-world situations. Despite high usability, however, a 5-day training with the NaviEar did not reach levels of automaticity that are indicative of perceptual feel. We propose that the test battery for automaticity may be used as a benchmark test for iterative research on perceptual experiences in sensory augmentation and sensory substitution.

Traditionally, the “Imagery Debate” has opposed two main camps: depictivism and descriptivism. This debate has essentially focused on the nature of the internal representations thought to be involved in imagery, without addressing at all the question of action. More recently, a third, “embodied” view is moving the debate into a new phase. The embodied approach focuses on the interdependence of perception, cognition and action, and in its more radical line this approach promotes the idea that perception is not a process involving internal world-models (representations). The anti-representationalist version of the embodied paradigm covers, among others that we shall not discuss here, two quite different positions, namely the enactive approach and sensorimotor theory. Up to now these two anti-representationalist accounts have generally been confounded. In this paper we will argue that despite some important commonalities, enactive and sensorimotor accounts come with distinctive theoretical traits with regard to their approach to imagery. These become manifest when critically examining the role they assign to sensorimotor engagements with the world. We shall argue that enactive and sensorimotor approaches are different in their understanding of the role of embodied action, and these different notions of embodiment lead to different explanatory accounts of perception and imagery. We propose that, due to existing ambiguities in enactivism, the sensorimotor theory is a better framework for a skill-based approach to imagery.

ABSTRACTDoerig et al. evaluate how current empirical theories approach access consciousness, but they neglect how they approach phenomenal consciousness – probably because most theories don’t deal with phenomenal consciousness at all. One exception is the sensorimotor theory, but Doerig et al. did not evaluate it as being directed to phenomenal consciousness.

Psychophysical studies suggest that different colors have different perceptual status: red and blue for example are thought of as elementary sensations whereas yellowish green is not. The dominant account for such perceptual asymmetries attributes them to specificities of the neuronal representation of colors. Alternative accounts involve cultural or linguistic arguments. What these accounts have in common is the idea that there are no asymmetries in the physics of light and surfaces that could underlie the perceptual structure of colors, and this is why neuronal or cultural processes must be invoked as the essential underlying mechanisms that structure color perception. Here, we suggest a biological approach for surface reflection properties that takes into account only the information about light that is accessible to an organism given the photopigments it possesses, and we show that now asymmetries appear in the behavior of surfaces with respect to light. These asymmetries provide a classification of surface properties that turns out to be identical to the one observed in linguistic color categorization across numerous cultures, as pinned down by cross cultural studies. Further, we show that data from psychophysical studies about unique hues and hue cancellation are consistent with the viewpoint that stimuli reported by observers as special are those associated with this singularity-based categorization of surfaces under a standard illuminant. The approach predicts that unique blue and unique yellow should be aligned in chromatic space while unique red and unique green should not, a fact usually conjectured to result from nonlinearities in chromatic pathways.

How could neural processes be associated with phenomenal consciousness? We present a way to answer this question by taking the counterintuitive stance that the sensory feel of an experience is not a thing that happens to us, but a thing we do: a skill we exercise. By additionally noting that sensory systems possess two important, objectively measurable properties, corporality and alerting capacity, we are able to explain why sensory experience possesses a sensory feel, but thinking and other mental processes do not. We are additionally able to explain why different sensory feels differ in the way they do.How could neural processes be associated with phenomenal consciousness? We present a way to answer this question by taking the counterintuitive stance that the sensory feel of an experience is not a thing that happens to us, but a thing we do: a skill we exercise. By additionally noting that sensory systems possess two important, objectively measurable properties, corporality and alerting capacity, we are able to explain why sensory experience possesses a sensory feel, but thinking and other mental processes do not. We are additionally able to explain why different sensory feels differ in the way they do.

The paper proposes a way of bridging the gapbetween physical processes in the brain and the ''felt''aspect of sensory experience. The approach is based onthe idea that experience is not generated by brainprocesses themselves, but rather is constituted by theway these brain processes enable a particular form of''give-and-take'' between the perceiver and theenvironment. From this starting-point we are able tocharacterize the phenomenological differences betweenthe different sensory modalities in a more principledway than has been done in the past. We are also ableto approach the issues of visual awareness andconsciousness in a satisfactory way. Finally weconsider a number of testable empirical consequences,one of which is the striking prediction of thephenomenon of ''change blindness''.

The recognition of multimorphemic French words was investigated using a procedure that allowed the position of first fixation of the eye to be manipulated and gaze durations to be recorded. The results of Experiment 1 indicated that prefixed and suffixed words were recognised most rapidly when the eye started at points at which the words' stem could be seen distinctly. In Experiment 2, gaze durations for prefixed words equated for surface frequency were longer for words with low-frequency rather than high-frequency stems. The findings support the idea that complex words are accessed in terms of their stem, and that the order in which affixes are listed in an entry is determined by the surface frequency of the entire word formed by the stem plus affix. Alternative accounts of the findings were considered.

Self-esteem/self-concept and aesthetics were measured in three groups. One group prior to orthodontic treatment, one group following completion of active orthodontic treatment and an untreated group. Improvement in dental and/or facial aesthetics does not necessarily lead to an increase in self esteem.

In a recent article, McConkie et al. (1989) proposed that, due to the rapid drop-off of visual acuity, the amount of visual information available from a word is maximal when the eye fixates the middle of the word, and decreases on both sides of this optimal viewing position with each letter of deviation. However, data on perceptual span have demonstrated that during a fixation, more letters are utilized to the right than to the left of the fixation point, which would predict that the optimal viewing position should be left of center. In a letter discrimination task, the ratio of the left/right asymmetry was determined and the probability of correct word recognition as a function of fixation location in the word was estimated. The predictions were highly compatible with empirical results on word recognition.

This paper attempts to apply psychophysical methodology, usually reserved for the study of low-level perceptual proocsses, to the study of language priming effects in bilingual subjects. Previous research using more traditional psycholinguistic techniques has demonstrated that bilinguals find words in one language harder to recognise when immediately preceded by a word of their other language. In the present experiments, this result was shown to remain robust even after the subjects had become very familiar with the experimental stimuli, thus suggesting that it is a highly automatised, irrepressible effect. The basic language priming effect was shown to be dependent on the neighbourhood characteristics (number of orthographically similar words in each language) of the prime words, but mainly at short prime exposures (>60 msec). At longer durations (428 msec), only the language of the prime (English or French) played a role.

McConkie, Kerr, Reddix, & Zola [(1988). Vision Research, 28, 1107–1118] demonstrated that the distributions of landing sites on a word tended to be gaussian in shape. They provided a detailed account of the behaviour of the eye once a target had been selected and a saccade initiated, but said little about the process of target selection itself. The purpose of this study was to take as a starting point the landing site distributions of McConkie et al., in particular the residuals derived from fitting the gaussians to the empirical data, and to explore by computer simulation a number of saccade targeting strategies in order to discover candidates that best accounted for the residual data. Our results indicate that the strategy that gives the best fit involves targeting the longest word in a right parafoveal window extending 20 characters to the right of the currently fixated word. The implications of this finding for models of reading are discussed.

The purpose of the present study was to compare the oculomotor behavior of readers scanning meaningful and meaningless materials. Four conditions were used-a normal-text-reading control condition, and three experimental conditions in which the amount of linguistic processing was reduced, either by presenting the subjects with repeated letter strings or by asking the subjects to search for a target letter in texts or letter strings. The results show that global eye-movement characteristics (such as saccade size and fixation duration), as well as local characteristics (such as word-skipping rate, landing site, refixation probability, and refixation position), are very similar in the four conditions. The finding that the eyes are capable of generating an autonomous oculomotor scanning strategy in the absence of any linguistic information to process argues in favor of the idea that such predetermined oculomotor strategies might be an important determinant of eye movements in reading. [ABSTRACT FROM AUTHOR]

Eye movements were recorded while subjects read passages of text repeatedly (Experiment 1) and while normal text and strings ofhomogeneous letters were fixated (Experiment 2). Text repetition decreased fixation durations and increased saccade size, presumably because it decreased attention demands. Irrespective ofrepetition, however, no distinct distribution of brief (express) fixations emerged. In Experiment 2, fixation durations were shorter and saccades were larger when strings of homogeneous letters were 'read,' indicating that this condition decreased attention demands. Again, however, no distinct distribution of express fixations emerged. These findings pose problems for the view that attentional processes determine the occurrence of brief (express) fixation durations in reading. Supplementary analyses of Experiments 1 and 2 suggested that visuospatial processing affected fixation durations, irrespective of linguistic processing demands. [ABSTRACT FROM AUTHOR]

Two experiments are described that measured lexical decision latencies and errors to five-letter French words with a single higher frequency orthographic neighbor and control words with no higher frequency neighbors. The higher frequency neighbor differed from the stimulus word by either the second letter (e.g., astre-autre) or the fourth letter ( chope-chose). Neighborhood frequency effects were found to interact with this factor, and significant interference was observed only to chope-type words. The effects of neighborhood frequency were also found to interact with the position of initial fixation in the stimulus word (either the second letter or the fourth letter). Interference was greatly reduced when the initial fixation was on the critical disambiguating letter (i.e., the letter p in chope). Moreover, word recognition was improved when subjects initially fixated the second letter relative to when they initially fixated the fourth letter of a five-letter word, but this second-letter advantage practically disappeared when the stimulus differed from a more frequent word by its fourth letter. The results are interpreted in terms of the interaction between visual and lexical factors in visual word recognition. [ABSTRACT FROM AUTHOR]

When a theoretical psychometric function is fitted to experimental data (as in the obtaining of a psychophysical threshold), maximum-likelihood or probit methods are generally used. In the present paper, the behavior of these curve-fitting methods is studied for the special case of forced-choice experiments, in which the probability of a subject's making a correct response by chance is not zero. A mathematical investigation of the variance of the threshold and slope estimators shows that, in this case, the accuracy of the methods is much worse, and their sensitivity to the way data are sampled is greater, than in the case in which chance level is zero. Further, Monte Carlo simulations show that, in practical situations in which only a finite number of observations are made, the mean threshold and slope estimates are significantly biased. The amount of bias depends on the curve-fitting method and on the range of intensity values, but it is always greater in forced-choice situations than when chance level is zero. [ABSTRACT FROM AUTHOR]

Psychologie Expérimentale, 28 rue Serpente, 75006 Paris, France. Current models of word recognition generally assume that word units orthographically similar to a stimulus word are involved in the visual recognition of this word. We refer to this set of orthographically similar words as an orthographic neighborhood. Two experiments are presented that investigate the ways in which the composition of this neighborhood can affect word recognition. The data indicate that the presence in the neighborhood of at least one unit of higher frequency than the stimulus word itself results in interference in stimulus word processing. Lexical decision latencies (Experiment 1) and gaze durations (Experiment 2) to words with one neighbor of higher frequency were significantly longer than to words without a more frequent neighbor. [ABSTRACT FROM AUTHOR]

Four experiments examined the relative use of retinal and extraretinal information in judging the location of a stimulus flash presented under normal lighting conditions in the temporal vicinity of an eye saccade. Two previous studies done under normal lighting conditions (N. Bischof & E. Kramer, 1968, and S. Mateeff, 1978) had hypothesized strong use of extraretinal information. The present study reexamined this work and showed that, in fact, two kinds of retinal effects had been neglected in these studies, and that these alone probably suffice to explain the results. The first retinal effect is related to differences between the response of the visual system to foveal and peripheral stimuli, and may be active even in the dark. The second retinal effect is related to the fact that smearing of the retinal image of the background occurs when the eye moves. [ABSTRACT FROM AUTHOR]

The effect of visibility on eye-movement parameters was investigated. As a measure of visibility, the notion of 'visual span' was introduced. A first experiment, in which a simple letter-recognition task was used, directly measured the changes in visual span produced by changing viewing distance and character spacing. The results of this experiment were used as a reference for a second experiment in which the same visibility changes were made, but in which subjects read short texts while their eye movements were monitored. Saccade sizes were affected not primarily by visual span, but by other factors, possibly related to word boundary detection or linguistic processing. Fixation durations appeared to be strongly affected by the proximity of the letters to the subject's acuity threshold. [ABSTRACT FROM AUTHOR]

This experiment investigates how information about six letter spaces to the right of the current fixation point is used to guide the eye in reading. It is found that low-quality cues such as word length can be extracted from this region sufficiently quickly to influence the size of the immediately following saccade. Linguistic processing of information from this region is also done, but only begins to influence the eye's behavior at the next fixation point, where fixation duration is affected. Subsequent eye-movement characteristics are more strongly influenced, but this influence is diffuse, that is, spread over a variety of eye-movement parameters, and takes about 1 sec to develop. [ABSTRACT FROM AUTHOR]

In this article, we present a simple agent which learns an internal representation of space without a priori knowledge of its environment, body, or sensors. The learned environment is seen as an internal space representation. This representation is isomorphic to the group of transformations applied to the environment. The model solves certain theoretical and practical issues encountered in previous work in sensorimotor contingency theory. Considering the mathematical description of the internal representation, analysis of its properties and simulations, we prove that this internal representation is equivalent to knowledge of space.

AbstractMastery of sensorimotor contingencies can be viewed as attunement to potentialities. In our view, these potentialities have wider application than recognized in Seth’s account of sensory presence, and should pertain to all of sensory experience. Instead of appealing only to a notion of counterfactual richness, we propose that the degree of sensory presence can be further specified in terms of bodiliness, insubordinateness, and grabbiness. While PPSMC can provide a possible implementation of a sensorimotor account of synesthesia, we suggest it should be rid of its representationalist interpretation.