Sleep and memory consolidation: motor performance and proactive interference effects in sequence learning Philippe Peigneux ULB 2015 09

Borragan, G., Urbain, C., Schmitz, R., Mary, A., & Peigneux, P. (2015). Sleep and memory consolidation: motor performance and proactive interference effects in sequence learning. Brain Cogn, 95, 54-61

That post-training sleep supports the consolidation of sequential motor skills remains debated. Performance improvement and sensitivity to proactive interference are both putative measures of long-term memory consolidation. We tested sleep-dependent memory consolidation for visuo-motor sequence learning using a proactive interference paradigm. Thirty-three young adults were trained on sequence A on Day 1, then had Regular Sleep (RS) or were Sleep Deprived (SD) on the night after learning. After two recovery nights, they were tested on the same sequence A, then had to learn a novel, potentially competing sequence B. We hypothesized that proactive interference effects on sequence B due to the prior learning of sequence A would be higher in the RS condition, considering that proactive interference is an indirect marker of the robustness of sequence A, which should be better consolidated over post-training sleep. Results highlighted sleep-dependent improvement for sequence A, with faster RTs overnight for RS participants only. Moreover, the beneficial impact of sleep was specific to the consolidation of motor but not sequential skills. Proactive interference effects on learning a new material at Day 4 were similar between RS and SD participants. These results suggest that post-training sleep contributes to optimizing motor but not sequential components of performance in visuo-motor sequence learning.

Into the looking glass: Literacy acquisition and mirror invariance in preschool and first-grade children. Régine Kolinsky ULB 2015 09

Fernandes, T., Leite, I., & Kolinsky, R. (2016, in press). Into the looking glass: Literacy acquisition and mirror invariance in preschool and first-grade children. Child Development. At what point in reading development does literacy impact object recognition and orientation processing? Is it specific to mirror images? To answer these questions, forty-six 5-7-year-old preschoolers and first graders performed two same-different tasks differing in the matching criterion - orientation-based vs. shape-based (orientation-independent) - on geometric shapes and letters. On orientation-based judgments, first graders outperformed preschoolers who had the strongest difficulty with mirrored pairs. On shape-based judgments, first graders were slower for mirrored than identical pairs, and even slower than preschoolers. This mirror cost emerged with letter knowledge. Only first graders presented worse shape-based judgments for mirrored and rotated pairs of reversible (e.g., b-d; b-q) than non-reversible (e.g., e-ә) letters, indicating readers’ difficulty in ignoring orientation-contrasts relevant to letters.

Does learning to read shape verbal working memory? Régine Kolinsky ULB 2015 09

Demoulin, C., & Kolinsky, R. (2016, in press). Does learning to read shape verbal working memory? Psychonomic Bulletin & Review . DOI 10.3758/s13423-015-0956-7. Many experimental studies have investigated the relationship between the acquisition of reading and working memory in a unidirectional way, attempting to determine to what extent individual differences in working memory can predict reading achievement. In contrast, very little attention has been dedicated to the converse possibility that learning to read shapes the development of verbal memory processes. In this paper, we present available evidence that advocates a more prominent role for reading acquisition on verbal working memory and then discuss the potential mechanisms of such literacy effects. First, the early decoding activities might bolster the development of subvocal rehearsal, which, in turn, would enhance serial order performance in immediate memory tasks. In addition, learning to read and write in an alphabetical system allows the emergence of phonemic awareness and finely tuned phonological representations, as well as of orthographic representations. This could improve the quality, strength, and precision of lexical representations, and hence offer better support for the temporary encoding of memory items and/or for their retrieval.

On the other side of the mirror: Priming in cognitive and social psychology Axel Cleeremans ULB 2015 09

Doyen, S., Klein, O., Simons, D., & Cleeremans, A. (2014). On the other side of the mirror: Priming in cognitive and social psychology. Social Cognition, 32 (Supplement: Understanding priming effects in social psychology), 12-32.


Over the past several years, two largely separate traditions have collided, leading to controversy over claims about priming. We describe and contrast the main accounts of priming effects in cognitive and social psychology, focusing especially on the role of awareness. In so doing, we consider one of the core points of contention, claims about the effects of subliminal priming. Whereas cognitive psychologists often are interested in exploring how priming operates with and without awareness, social psychologists more commonly assume subliminality in order to bolster claims about the automaticity of priming. We discuss the criteria necessary to claim that a stimulus was processed entirely without awareness, noting the challenges in meeting those criteria. Finally, we identify three sources of conflict between the fields: awareness, replicability, and the nature of the underlying processes. We close by proposing resolutions for each of them. "

Dissociating conscious and unconscious learning with objective and subjective measures Axel Cleeremans ULB 2015 09

Gaillard, V., Cleeremans, A., & Destrebecqz, A. (2014). Dissociating conscious and unconscious learning with objective and subjective measures. Clinical EEG and Neuroscience, 45(1), 50-56.


According to functionalist theories, consciousness can be defined by the functions that it serves and by the way it contributes to cognition. For example, when trying to establish dissociations between conscious and unconscious knowledge, conscious representations would be identified by the fact that they allow cognitive control or successful identification or recollection, assessed by verbal reports or forced-choice tasks. Even though the functionalist approach has brought about important dissociation results concerning conscious and unconscious cognition, critics emphasize that it does not account for the qualitative properties of conscious experience. Phenomenal theories are precisely based on the notion that conscious representations are such that it feels like something to have these representations. Thus, one way to assess conscious knowledge is to ask people, after they have produced a forced-choice response, to identify their mental states through the use of subjective confidence ratings, in which they discriminate between a complete guess and a response based on some feeling of knowing. However, these 2 approaches are not mutually exclusive. In this article, we review a series of studies showing that the joint use of objective judgments about some external stimuli and about one’s own subjective knowledge concerning these stimuli, provides new insights into the putative dissociation between conscious and unconscious knowledge in learning.

The temporal dynamic of automatic inhibition of irrelevant actions Axel Cleeremans ULB 2015 09

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.

The relationship between human agency and embodiment Axel Cleeremans ULB 2015 09

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.

How can we measure awareness? An overview of current methods Axel Cleeremans ULB 2015 09

Timmermans, B., & Cleeremans, A. (2015). How can we measure awareness? An overview of current methods. In M. Overgaard (Ed.), Behavioural Methods in Consciousness Research, Oxford: Oxford University Press, pp. 21-46.

Does level of processing affect the transition from unconscious to conscious perception? Axel Cleeremans ULB 2015 09

Anzulewicz, A., Asanowicz, D. , Windey, B., Paulewicz, B., Wierzchon, M. & Cleeremans, A. (2015). Does level of processing affect the transition from unconscious to conscious perception? Consciousness and Cognition, 36, 1-11.


Recently, Windey, Gevers, and Cleeremans (2013) proposed a level of processing (LoP) hypothesis claiming that the transition from unconscious to conscious perception is influ- enced by the level of processing imposed by task requirements. Here, we carried out two experiments to test the LoP hypothesis. In both, participants were asked to classify briefly presented pairs of letters as same or different, based either on the letters’ physical features (a low-level task), or on a semantic rule (a high-level task). Stimulus awareness was mea- sured by means of the four-point Perceptual Awareness Scale (PAS). The results showed that low or moderate stimulus visibility was reported more frequently in the low-level task than in the high-level task, suggesting that the transition from unconscious to conscious perception is more gradual in the former than in the latter. Therefore, although alternative interpretations remain possible, the results of the present study fully support the LoP hypothesis.


Mechanisms of conscious and unconscious learning