The normal variability in alertness we experience in daily tasks is rarely taking into account in cognitive neuroscience. Here we studied neurobehavioral dynamics of cognitive control with decreasing alertness. We used the classic Simon Task where participants hear the word "left" or "right" in the right or left ear, eliciting slower responses when the word and the side are incongruent -the conflict effect. Participants performed the task both while fully awake and while getting drowsy, allowing for the characterisation of alertness modulating cognitive control. The changes in the neural signatures of conflict from local theta oscillations to a longdistance distributed theta network suggests a reconfiguration of the underlying neural processes subserving cognitive control when affected by alertness fluctuations.

Short-term memory has mostly been investigated with verbal or visuospatial stimuli and less so with other categories of stimuli. Moreover, the influence of sensory modality has been explored almost solely in the verbal domain. The present study compared visual and auditory short-term memory for different types of materials, aiming to understand whether sensory modality and material type can influence short-term memory performance. Furthermore, we aimed to assess if music expertise can modulate memory performance, as previous research has reported better auditory memory (and to some extent, visual memory), and better auditory contour recognition for musicians than non-musicians. To do so, we adapted the same recognition paradigm (delayed-matching to sample) across different types of stimuli. In each trial, participants (musicians and non-musicians) were presented with two sequences of events, separated by a silent delay, and had to indicate whether the two sequences were identical or different. The performance was compared for auditory and visual materials belonging to three different categories: (1) verbal (i.e., syllables); (2) nonverbal (i.e., that could not be easily denominated) with contour (based on loudness or luminance variations); and (3) nonverbal without contour (pink noise sequences or kanji letters sequences). Contour and no-contour conditions referred to whether the sequence can entail (or not) a contour (i.e., a pattern of up and down changes) based on non-pitch features. Results revealed a selective advantage of musicians for auditory no-contour stimuli and for contour stimuli (both visual and auditory), suggesting that musical expertise is associated with specific short-term memory advantages in domains close to the trained domain, also extending cross-modally when stimuli have contour information. Moreover, our results suggest a role of encoding strategies (i.e., how the material is represented mentally during the task) for short-term-memory performance.

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Summary Several factors influencing dream recall frequency (DRF) have been identified, but some remain poorly understood. One way to study DRF is to compare cognitive processes in low and high dream recallers (LR and HR). According to the arousal‐retrieval model, long‐term memory encoding of a dream requires wakefulness while its multisensory short‐term memory is still alive. Previous studies showed contradictory results concerning short‐term memory differences between LR and HR. It has also been found that extreme DRFs are associated with different electrophysiological traits related to attentional processes. However, to date, there is no evidence for attentional differences between LR and HR at the behavioural level. To further investigate attention and working memory in HR and LR, we used a newly‐developed challenging paradigm called “MEMAT” (for MEMory and ATtention), which allows the study of selective attention and working memory interaction during memory encoding of non‐verbal auditory stimuli. We manipulated the difficulties of the distractor to ignore and of the memory task. The performance of the two groups were not differentially impacted by working memory load. However, HR were slower and less accurate in the presence of a hard rather than easy to‐ignore distractor, while LR were much less impacted by the distractor difficulty. Therefore, we show behavioural evidence towards less resistance to hard‐to‐ignore distractors in HR. Using a challenging task, we show for the first time, attentional differences between HR and LR at the behavioural level. The impact of auditory attention and working memory on dream recall is discussed.

Draft version 28.03.2020. This paper has not been peer reviewed. Please do not copy or cite without author's permission. Short-term memory has mostly been investigated with verbal or visuospatial stimuli and less so with other categories of stimuli. Moreover, the influence of sensory modality has been explored almost solely in the verbal domain. The present study used the same experimental paradigm to investigate auditory and visual short-term memory for different types of stimuli. In each trial, participants were presented with two sequences of events, separated by a silent delay, and had to indicate whether the two sequences were identical or different. Performance in this recognition (delayed-matching-to-sample) paradigm was compared for materials that were either verbal (i.e., chained syllables without meaning) or nonverbal (i.e., not easily described by verbal labels). For the latter ones, the event sequence could either entail a contour, which is a pattern of up and down changes (based on non-pitch features), or not. All materials were implemented in both auditory and visual modalities. As previous research has reported better auditory memory (and to some extent, visual memory), and better auditory contour recognition for musicians than non-musicians, the recognition tasks were performed by a group of musicians and a group of non-musicians. Results revealed a selective advantage of musicians for the auditory no-contour stimuli and for the contour stimuli (both visual and auditory), suggesting that musical expertise is associated with specific short-term memory advantages in domains close to the trained domain, even extending cross-modally. These findings offer new insights into the role of encoding strategies and their effect on short-term memory performance across modalities.

18Humans are remarkably capable of adapting their behaviour flexibly based on rapid situational 19 changes: a capacity termed cognitive control. Intuitively, cognitive control is thought to be affected by 20 the state of alertness, for example, when sleepy or drowsy, we feel less capable of adequately 21implementing effortful cognitive tasks. Although scientific investigations have focused on the effects 22 of sleep deprivation and circadian time, little is known about how natural fluctuations in alertness in 23 the regular awake state affect cognitive control. Here we combined a conflict task in the auditory 24 domain with neurodynamics -EEG recordings-to test how neural and behavioural markers of conflict 25processing are affected by fluctuations in arousal. Using a novel computational method, we 26 segregated alert and drowsy trials from a three hour testing session and observed that, although 27 participants were generally slower, the typical slower responses to conflicting information, compared 28to non-conflicting information, was still intact, as well as the effect of previous trials (i.e. conflict 29 adaptation). However, the behaviour was not matched by the typical neural markers of cognitive 30control -local medio-frontal theta-band power changes-, that participants showed during full alertness. 31Instead, a decrease in power of medio-frontal theta was accompanied by an increase in long-range 32 information sharing (connectivity) between brain regions in the same frequency band. The results 33show the resilience of the human cognitive control system when affected by internal fluctuations of 34 our arousal state and suggests a neural compensatory mechanism when the system is under 35physiological pressure due to diminished alertness. 36