Chetail, F. & Content, A. What Is the Difference Between OASIS and OPERA? Roughly Five Pixels: Orthographic Structure Biases the Perceived Length of Letter Strings. Psychological Science, 25 (1), 243-249.
A thorough understanding of monosyllabic-word-recognition processes, in contrast with multisyllabic-word processing, has accumulated over the past decades. One fundamental challenge regarding multisyllabic words concerns their parsing into smaller units and the nature of the cues determining the parsing. We propose that the organization of consonant and vowel letters provides powerful cues for parsing, and we present data from a new task showing that a word’s orthographic structure, as determined by the number of vowel-letter clusters, influences estimations of its length. Words were briefly presented on a computer screen, and participants had to estimate word length by drawing a line on the screen with the mouse. In three experiments, participants estimated words comprising fewer orthographic units as shorter than words comprising more units even though the words matched for number of letters. Further results demonstrated that the length bias was driven by orthographic information and not by phonological structure.
Voss, M., Chambon, V., Wenke, D., Kühn, S., & Haggard, P. (2017). In and out of control: brain mechanisms linking fluency of action selection to self-agency in patients with schizophrenia. Brain, 140(8), 2226–2239. https://doi.org/10.1093/brain/awx136
Sense of agency refers to the feeling of control over one’s actions, and their consequences. It involves both predictive processes linked to action control, and retrospective ‘sense-making’ causal inferences. Schizophrenia has been associated with impaired predictive processing, but the underlying mechanisms that impair patients’ sense of agency remain unclear. We introduce a new ‘prospective’ aspect of agency and show that subliminally priming an action not only influences response times, but also influences reported sense of agency over subsequent action outcomes. This effect of priming was associated with altered connectivity between frontal areas and the angular gyrus. The effects on response times and on frontal action selection mechanisms were similar in patients with schizophrenia and in healthy volunteers. However, patients showed no effects of priming on sense of agency, no priming-related activation of angular gyrus, and no priming-related changes in fronto-parietal connectivity. We suggest angular gyrus activation reflects the experiences of agency, or non-agency, in part by processing action selection signals generated in the frontal lobes. The altered action awareness that characterizes schizophrenia may be due to impaired communication between these areas.
Vanbrabant K., Boddez Y., Verduyn P., Mestdagh M., Hermans D., Raes F. (2015). A new approach for modeling generalization gradients: A case for hierarchical models. Frontiers in Psychology, 6, art.nr. 652, 1-10.
Van Lier J., Vervliet B., Boddez Y., Raes F. (2014). “Why is everyone always angry with me?!”: When thinking ‘why’ leads to generalization. Journal of Behavior Therapy and Experimental Psychiatry, 47, 34-41.
105. Pegado, F., Comerlato, E., Ventura, F., Jobert, A., Nakamura, K., Buiatti, M., Ventura, P., Dehaene-Lambertz, G., Kolinsky, R., Morais, J., Braga, L. W., Cohen, L., & Dehaene, S. (2014). Timing the impact of literacy on visual processing. Proceedings of the National Academy of Sciences of the United States of America, 111(49), E5233–E5242. doi: 10.1073/pnas.1417347111.
Learning to read requires the acquisition of an efficient visual procedure for quickly recognizing fine print. Thus, reading practice could induce a perceptual learning effect in early vision. Using functional magnetic resonance imaging (fMRI) in literate and illiterate adults, we previously demonstrated an impact of reading acquisition on both high- and low-level occipitotemporal visual areas, but could not resolve the time course of these effects. To clarify whether literacy affects early vs. late stages of visual processing, we measured event-related potentials to various categories of visual stimuli in healthy adults with variable levels of literacy, including completely illiterate subjects, early-schooled literate subjects, and subjects who learned to read in adulthood (ex-illiterates). The stimuli included written letter strings forming pseudowords, on which literacy is expected to have a major impact, as well as faces, houses, tools, checkerboards, and false fonts. To evaluate the precision with which these stimuli were encoded, we studied repetition effects by presenting the stimuli in pairs composed of repeated, mirrored, or unrelated pictures from the same category. The results indicate that reading ability is correlated with a broad enhancement of early visual processing, including increased repetition suppression, suggesting better exemplar discrimination, and increased mirror discrimination, as early as ∼100–150 ms in the left occipitotemporal region. These effects were found with letter strings and false fonts, but also were partially generalized to other visual categories. Thus, learning to read affects the magnitude, precision, and invariance of early visual processing.
Atas, A., & Cleeremans, A. (2015). The temporal dynamic of automatic inhibition of irrelevant actions. Journal of Experimental Psychology: Human Perception and Performance, 41(2), 289-305.
Motor inhibition can occur even without conscious perception and any voluntary effort. Although it is now clear that such an inhibitory process needs time to unfold, its exact temporal dynamic remains to be elucidated. Therefore, the present study aims to examine the impact of various temporal factors on automatic motor inhibition using the masked priming task. Results shows that this process can be modulated by any factor that introduces time between the mask onset and the execution of target response, whether it stems from a purely external origin (mask-target SOA), a purely internal origin (spontaneous reaction time [RT] fluctuations), or a mix of both (RT fluctuations from the target sequence). Moreover, when the external temporal factor could not determine the direction of prime influence, the RT fluctuations had the strongest impact on the priming effect. These RT fluctuations are plausibly because of spontaneous trial-to-trial changes from more impulsive and error-prone decisions to more cautious and accurate decisions to the target. Indeed, both accuracy and speed were equally required during the task, but both requirements are impossible to achieve perfectly in every trial. This suggests that fluctuations in the level of caution in voluntary decisions can modulate unconscious and involuntary motor inhibition.
Chetail, F., Drabs, V. & Content, A. The role of consonant/vowel organization in perceptual discrimination. Journal of Experimental Psychology: Learning, Memory and Cognition, 2014 Apr 21. [Epub ahead of print], doi: 10.1037/a0036166.
According to a recent hypothesis, the CV pattern (i.e., the arrangement of consonant and vowel letters) constrains the mental representation of letter strings, with each vowel or vowel cluster being the core of a unit.
Six experiments with the same/different task were conducted to test whether this structure is extracted prelexically. In the mismatching trials, the targets were pseudowords built by the transposition of 2 adjacent letters from base words. In one condition, the pseudowords had the same number of vowel clusters as the base word, whereas in another condition, the transposition modified the number of vowel clusters (e.g., poirver: 2 vowel clusters vs. povirer: 3 vowel clusters, from POIVRER: 2 vowel clusters). In Experiment 1, pseudowords with a different number of vowel clusters were more quickly processed than pseudowords preserving the CV structure of their base word. Experiment 2 further showed that this effect was not due to changes in syllabic structure. In Experiment 3, the pattern of results was also replicated when the category (consonant or vowel) of the transposed letters was strictly equated between conditions. Experiments 4 and 5 confirmed that the effects were not attributable to lexical processing, to differences in letter identity, or to the position of transpositions. The results suggest that the orthographic representation of letter strings is influenced by the CV pattern at an early, prelexical processing stage.
Caspar, E., Cleeremans, A., & Haggard, P. (2015). The relationship between human agency and embodiment. Consciousness & Cognition, 33, 226-236.
Humans regularly feel a sense of agency (SoA) over events where the causal link between action and outcome is extremely indirect. We have investigated how intermediate (here, a robotic hand) events that intervene between action and outcome may alter SoA, using intentional binding measures. The robotic hand either performed the same movement as the participant (active congruent), or performed a similar movement with another finger (active incongruent). Binding was significantly reduced in the active incongruent relative to the active congruent condition, suggesting that altered embodiment influences SoA. However, binding effects were comparable between a condition where the robot hand made a congruent movement, and conditions where no robot hand was involved, suggest- ing that intermediate and embodied events do not reduce SoA. We suggest that human sense of agency involves both statistical associations between intentions and arbitrary out- comes, and an effector-specific matching of sensorimotor means used to achieve the outcome.
Li, F., Jiang, S., Guo, X., Yang, Z, & Dienes, Z. (2013). The nature of the memory buffer in implicit learning: Learning Chinese tonal symmetries. Consciousness and Cognition 22, 920-930
Previous research has established that people can implicitly learn chunks, which (in terms of formal language theory) do not require a memory buffer to process. The present study explores the implicit learning of nonlocal dependencies generated by higher than finite state grammars, specifically, Chinese tonal retrogrades (i.e. centre embeddings generated from a context-free grammar) and inversions (i.e. cross-serial dependencies generated from a mildly context-sensitive grammar), which do require buffers (for example, last in-first out and first in-first out, respectively). People were asked to listen to and memorize artificial poetry instantiating one of the two grammars; after this training phase, people were informed of the existence of rules and asked to classify new poems, while providing attributions of the basis of their judgments. People acquired unconscious structural knowledge of both tonal retrogrades and inversions. Moreover, inversions were implicitly learnt more easily than retrogrades constraining the nature of the memory buffer in computational models of implicit learning.
Fernandes, T. & Kolinsky, R (Eds.) Special issue of Frontiers in Developmental Psychology, “The impact of learning to read on visual processing” . Also published as Frontiers ebook: Fernandes, T. & Kolinsky, R. (2016), Eds. “The impact of learning to read on visual processing”. Lausanne: Frontiers Media. doi: 10.3389/978-2-88919-716-3.
Reading is at the interface between the vision and spoken language domains. An emergent bulk of research indicates that learning to read strongly impacts on non-linguistic visual object processing, both at the behavioral level (e.g., on mirror image processing – enantiomorphy–) and at the brain level (e.g., inducing top-down effects as well as neural competition effects). Yet, many questions regarding the exact nature, locus, and consequences of these effects remain hitherto unanswered.
The current Special Topic aims at contributing to the understanding of how such a cultural activity as reading might modulate visual processing by providing a landmark forum in which researchers define the state of the art and future directions on this issue.
Mertens, G., & De Houwer, J. (2016). The impact of a context switch and context instructions on the return of verbally conditioned fear. Journal of Behavior Therapy and Experimental Psychiatry, 51, 10-18.
Background and Objectives: Repeated exposure to a conditioned stimulus can lead to a reduction of conditioned fear responses towards this stimulus (i.e., extinction). However, this reduction is often fragile and sensitive to contextual changes. In the current study, we investigated whether extinction of fear responses established through verbal threat instructions is also sensitive to contextual changes. We additionally examined whether verbal instructions can strengthen the effects of a context change.
Methods: Fifty-two participants were informed that one colored rectangle would be predictive of an electrocutaneous stimulus, while another colored rectangle was instructed to be safe. Half of these participants were additionally informed that this contingency would only hold when the background of the computer screen had a particular color but not when it had another color. After these instructions, the participants went through an unannounced extinction phase that was followed by a context switch.
Results: Results indicate that extinguished verbally conditioned fear responses can return after a context switch, although only as indexed by self-reported expectancy ratings. This effect was stronger when participants were told that CS-US contingency would depend on the background color, in which case a return of fear was also observed on physiological measures of fear.
Limitations: Extinction was not very pronounced in this study, possibly limiting the extent to which return of fear could be observed on physiological measures.
Conclusions: Contextual cues can impact the return of fear established via verbal instructions. Verbal instructions can further strengthen the contextual control of fear.
￼Windey, B., Vermeiren, A., Atas, A., & Cleeremans, A. (2014). The graded and dichotomous nature of visual awareness. Philosophical Transactions of the Royal Society B, 369: 20130282
Is our visual experience of the world graded or dichotomous? Opposite pre- theoretical intuitions apply in different cases. For instance, when looking at a scene, one has a distinct sense that our experience has a graded character: one cannot say that there is no experience of contents that fall outside the focus of attention, but one cannot say that there is full awareness of such contents either. By contrast, when performing a visual detection task, our sense of having perceived the stimulus or not exhibits a more dichoto- mous character. Such issues have recently been the object of intense debate because different theoretical frameworks make different predictions about the graded versus dichotomous character of consciousness. Here, we review both relevant empirical findings as well as the associated theories (i.e. local recurrent processing versus global neural workspace theory). Next, we attempt to reconcile such contradictory theories by suggesting that level of processing is an often-ignored but highly relevant dimension through which we can cast a novel look at existing empirical findings. Thus, using a range of different stimuli, tasks and subjective scales, we show that proces- sing low-level, non-semantic content results in graded visual experience, whereas processing high-level semantic content is experienced in a more dichotomous manner. We close by comparing our perspective with existing proposals, focusing in particular on the partial awareness hypothesis.
Takano K., Boddez Y., Raes F. (2016). I sleep with my Mind’s eye open: Cognitive arousal and overgeneralization underpin the misperception of sleep. Journal of Behavior Therapy and Experimental Psychiatry, 52, 157-165.
Stenner, M.-P., Bauer, M., Sidarus, N., Heinze, H.-J., Haggard, P., & Dolan, R.J. 2014 Subliminal action priming modulates the perceived intensity of sensory action consequences. Cognition, 30(2), 227–235.
The sense of control over the consequences of one’s actions depends on predictions about these consequences. According to an influential computational model, consistency between predicted and observed action consequences attenuates perceived stimulus intensity, which might provide a marker of agentic control. An important assumption of this model is that these predictions are generated within the motor system. However, previous studies of sensory attenuation have typically confounded motor-specific perceptual modulation with perceptual effects of stimulus predictability that are not specific to motor action. As a result, these studies cannot unambiguously attribute sensory attenuation to a motor locus. We present a psychophysical experiment on auditory attenuation that avoids this pitfall. Subliminal masked priming of motor actions with compatible prime– target pairs has previously been shown to modulate both reaction times and the explicit feeling of control over action consequences. Here, we demonstrate reduced perceived loudness of tones caused by compatibly primed actions. Importantly, this modulation results from a manipulation of motor processing and is not confounded by stimulus predictability. We discuss our results with respect to theoretical models of the mechanisms underlying sensory attenuation and subliminal motor priming.