Initiative apathy trait underlies individual differences in the ability to anticipate and expend cognitive effort in cost-benefit decision-making tasks.

Initiative apathy is the most disabling form of apathy, prevalent both in neuropsychiatric pathologies and in the healthy population. This apathy has been specifically associated with functional abnormalities of the anterior cingulate cortex, a key structure underlying Effort-based Decision-Making (EDM). The main aim of the present study was to explore, for the first time, the cognitive and neural effort mechanisms of initiative apathy, by distinguishing the steps of effort anticipation and effort expenditure and the potential modulating effect of motivation. We conducted an EEG study in 23 subjects with specific subclinical initiative apathy and 24 healthy subjects with no apathy. The subjects had to complete two effort tasks. The analysis of behavioral choices, CNV, and mPFC theta power highlighted that initiative apathy is associated with effort avoidance and impairments of effort anticipation and effort expenditure that suggest EDM deficits. Better knowledge of these impairments should aid the development of new, more targeted therapeutic interventions necessary for reducing the debilitating consequences of initiative apathy.

Specific mechanisms underlying executive and emotional apathy: A phenotyping study.

Apathy is a behavioral symptom prevalent both in neuropsychiatric pathologies and in the healthy population. However, the knowledge of the cognitive and neural mechanisms underlying apathy is still very limited, even if clinical and fMRI data support the existence of three forms of apathy (executive, emotional, initiative). These forms could be explained by the alteration of specific mechanisms. This present study's aim is to specify the cognitive and neuronal mechanisms of executive and emotional apathy. We used an EEG study conducted on 68 subjects comprising two groups of young people with specific executive or emotional phenotypes of apathy and one group with no apathy. Despite having symptom of apathy, participants were free of any neurological, metabolic, or psychiatric diagnoses and with high education. Two tasks were used: the DPX for cognitive control and the MID for motivation. Our results showed that distinct mechanisms underlie these two forms of apathy, and, for the first time, we specified these mechanisms. A deficit of the proactive control mode, reflected by a reduced probe-N2 amplitude in AY trials, underlies the executive form of apathy (p < .03), whereas liking motivational blunting, highlighted by a reduced LPP amplitude for financial loss, characterizes the emotional form (p < .04). The main limit of the results is that generalizability to the general population may be reduced since the apathetic samples were chosen for having a specific form of apathy. To conclude, better knowledge of these mechanisms informs new, more targeted treatments, both pharmacological and non-pharmacological, necessary for reducing the debilitating consequences of apathy.

Mind-wandering does not always rhyme with proactive functioning! Changes in the temporal dynamics of the mPFC-mediated theta oscillations during moments of mind-wandering.

The reduced engagement of the cognitive control network has been documented widely during mind-wandering (MW). However, it remains unknown how MW affects the neural dynamics of cognitive control processes. From this perspective, we explored neural dynamics mediated by the medial prefrontal cortex (mPFC). Their engagement can be both transient (or reactive) and anticipated (or proactive). A total of fortyseven healthy subjects (37 females) were engaged in a long-lasting sustained-attention Go/NoGo task. Subjective probes were used to detect MW episodes. Channel-based EEG time-frequency analysis was performed to measure the theta oscillations, an index of the mPFC activity. The theta oscillations were computed immediately after conflictual NoGo trials to explore the reactive engagement of the mPFC. Proactive control was measured on the Go trials preceded the NoGo. Behaviorally, periods of MW were associated with an increase in errors and in RT variability in comparison to on-task periods. The analysis of the frontal midline theta power (MFθ) revealed that MW periods were associated with lower anticipated/proactive engagement and similar transient/reactive engagement of mPFC-mediated processes. Moreover, the communication between the mPFC and the DLPFC, as revealed by the poorer theta synchronization between these two regions, was also impaired during MW periods. Our results provide new insights about performance impairment during MW. They could be an important step in improving the existing understanding of the altered performances that are reported for some disorders that are known to be associated with excessive MW.

Disentangling racing thoughts from mind wandering in adult attention deficit hyperactivity disorder.

Introduction: Mental restlessness reported by adult with Attention Deficit Hyperactivity Disorder (ADHD) has been mainly explained by excessive mind wandering. However, the description of a mind constantly on the go is also akin to racing thoughts, predominantly described in bipolar disorder. This paper aimed at disentangling mind wandering from racing thoughts in adult with ADHD. Associations between those mental phenomena and the ADHD symptomatology were also investigated. Methods: To this aim, 84 adults with ADHD completed self-reported questionnaires, including the Mind Wandering-Deliberate and Mind Wandering-Spontaneous questionnaires, the Racing and Crowded Thoughts Questionnaire and the Daydreaming Frequency Scale. Factorial analysis and multiple linear regressions were performed. Results: The factor analysis yielded a two-factor solution. The first factor encompassed the three facets of racing thoughts and was predicted by emotional lability. The second comprised deliberated-MW, spontaneous-MW and daydreaming, but was neither related to the ADHD symptoms, nor functional impairment. Discussion: These findings suggest that MW and racing thoughts are two distinguishable mental phenomena. Racing thoughts appear to be a relevant hypothesis to explain the mental restlessness in adult ADHD.

The stability of multidimensional subclinical apathy during a pandemic and its relations to psycho-behavioral factors.

Apathy is a clinical symptom prevalent in many neuropsychiatric pathologies. Subclinical apathy is found in 35% of the general population. Despite high prevalence and negative consequences, underlying mechanisms are poorly understood, perhaps because the concept of apathy is one-dimensional. The current investigation aims to address the incidence of multidimensional apathetic trait in three distinct forms in a student population, to specify its determinants and to evaluate its stability during a global pandemic. Two online surveys, conducted 1 year apart on two separate cohorts of university students, with qualitative measures and validated scales. The final analysis included, respectively, 2789 and 1678 students. The three forms of apathetic trait were present, with the same debilitating consequences as apathetic symptom but independent determinants. Executive apathy was predicted by depressive symptoms, emotional apathy by motivational deficit and initiative apathy comprised a mixed executive-emotional form and a pure deficit of action initiation. The three forms of subclinical apathy remained similar in the context of increased depressive symptoms due to a global pandemic. This study confirmed the presence and independence of three forms of subclinical apathy in healthy students, which remained similar even in the light of increased depressive scores. These results shed light on cognitive and neuronal mechanisms underlying multidimensional apathy, allowing new, targeted treatments.

Neurocognitive analyses reveal that video game players exhibit enhanced implicit temporal processing.

Winning in action video games requires to predict timed events in order to react fast enough. In these games, repeated waiting for enemies may help to develop implicit (incidental) preparation mechanisms. We compared action video game players and non-video game players in a reaction time task involving both implicit time preparations and explicit (conscious) temporal attention cues. Participants were immersed in virtual reality and instructed to respond to a visual target appearing at variable delays after a warning signal. In half of the trials, an explicit cue indicated when the target would occur after the warning signal. Behavioral, oculomotor and EEG data consistently indicate that, compared with non-video game players, video game players better prepare in time using implicit mechanisms. This sheds light on the neglected role of implicit timing and related electrophysiological mechanisms in gaming research. The results further suggest that game-based interventions may help remediate implicit timing disorders found in psychiatric populations.

How visual attention span and phonological skills contribute to N170 print tuning: An EEG study in French dyslexic students.

Developmental dyslexia is a disorder characterized by a sustainable learning deficit in reading. Based on ERP-driven approaches focusing on the visual word form area, electrophysiological studies have pointed a lack of visual expertise for written word recognition in dyslexic readers by contrasting the left-lateralized N170 amplitudes elicited by alphabetic versus non-alphabetic stimuli. Here, we investigated in 22 dyslexic participants and 22 age-matched control subjects how two behavioural abilities potentially affected in dyslexic readers (phonological and visual attention skills) contributed to the N170 expertise during a word detection task. Consistent with literature, dyslexic participants exhibited poorer performance in these both abilities as compared to healthy subjects. At the brain level, we observed (1) an unexpected preservation of the N170 expertise in the dyslexic group suggesting a possible compensatory mechanism and (2) a modulation of this expertise only by phonological skills, providing evidence for the phonological mapping deficit hypothesis.

Impact of motivation on cognitive control in the context of vigilance lowering: an ERP study.

We assessed the effects of time-on-task on cognitive control expressed by the CRN/Nc and the extent to which motivation modulates this relationship. We utilized two groups of participants, who were told that their performance would (evaluation condition) or would not (control condition) be evaluated online. Both groups performed a version of the Eriksen Flanker Task for 60 min. We observed classical vigilance lowering, manifested by a progressive performance decline with time-on-task, in the control, but not in the evaluation, condition. In the latter, performance remained stable throughout the task. ERP analysis indicated the same interaction in our main component of interest, the CRN/Nc, whose amplitude decreased from the first to the last period in the control condition but remained stable over time in the evaluation condition. To our knowledge, this study is the first to demonstrate the impact of motivation on monitoring processes as indexed by the correct response negativity, in the context of a prolonged task. Vigilance lowering caused by a repetitive and prolonged flanker task, results in compromised response control and compromised control of correct responses. Our results suggest that alterations in ACC functioning may underlie vigilance decline and can be viewed as evidence that the action monitoring functions of the ACC can be positively affected by motivation.

Impaired Frontal Midline Theta During Periods of High Reaction Time Variability in Schizophrenia.

BACKGROUND: Impairment in cognitive control is one of the most significant cognitive deficits in schizophrenia. Although it has generally been associated with altered engagement of lateral and medial prefrontal cortices, how attention fluctuations affect this engagement is still not known. In this context, we explored sustained (or proactive) and transient (or reactive) control engagement by investigating frontal theta-band oscillations during periods of low- and high-performance instability, assumed to represent intraindividual attentional fluctuations. METHODS: A total of 25 patients with schizophrenia (16 males) and 25 healthy matched control subjects (18 males) performed a long-sustained Go/NoGo task coupled with electroencephalographic recording. Proactive control was explored through frontal lateral theta during trial-by-trial conflict (Go N-1/Go N+1), whereas reactive control was explored through frontal midline theta and the N2 component during current-trial conflict (Go/NoGo). Variance in the time course of reaction time (RT) was computed to identify periods of low and high RT variability in each subject. RESULTS: Patients with schizophrenia exhibited no frontal lateral theta activity regardless of the RT variability periods, whereas in control subjects, this activity was preserved only during periods of low RT variability (less error prone). During these periods, patients exhibited preserved midline frontal theta activity and N2. However, during high RT variability periods (more error prone), the midline theta activity was impaired in patients but preserved in control subjects. CONCLUSIONS: Our results reveal that the efficient engagement of reactive control in patients with schizophrenia and of proactive control in control subjects was state dependent. The findings highlight the importance of accounting for attentional fluctuations when investigating cognitive control impairment in schizophrenia.

Conjoint fluctuations of PFC-mediated processes and behavior: An investigation of error-related neural mechanisms in relation to sustained attention.

The ability to detect errors, which derives from the medial prefrontal cortex (mPFC), is crucial to maintain attention over a long period of time. While impairment of this ability has been reported in patients with sustained attention disruption, the role mPFC-mediated processes play in the intra-individual fluctuation of sustained attention remains an open question. In this context, we computed the variance time course of reaction time (RT) of 42 healthy individuals to distinguish intra-individual periods of low and high performance instability, assumed to represent optimal and suboptimal attentional states, when performing a sustained Go/NoGo task. Analysis of the neurophysiological mechanisms of response monitoring revealed a specific reduction in the error-related negativity (ERN) amplitude and frontal midline theta power during periods of high compared to low RT variability, but only in individuals with a higher standard deviation of reaction time (SD-RT). Concerning post-error adaptation, an increase in the correct-related negativity (CRN) amplitude as well as the frontal lateral theta power on trials following errors was observed in individuals with lower SD-RT but not in those with higher SD-RT. Our results thus show that individuals with poor sustained attention ability exhibit altered post-error adaptation and attentional state-dependent efficiency of error monitoring. Conversely, individuals with good sustained attention performances retained their post-error adaptation and response monitoring regardless of the attentional periods. These findings reveal the critical role of the action-monitoring system in intra-individual behavioral stability and highlight the importance of considering attentional states when studying mPFC-mediated processes, especially in subjects with low sustained attention ability.

Investigation of electrophysiological precursors of attentional errors in schizophrenia: Toward a better understanding of abnormal proactive control engagement.

Impaired cognitive control has been associated with the occurrence of attentional errors in those with schizophrenia. However, the extent of altered proactive or reactive control underlying such errors is still unknown. Twenty-two patients with schizophrenia and 21 healthy matched controls performed a detection task (i.e., the continuous temporal expectancy task). Electrophysiological measures of proactive and reactive control were based on two periods of interest: during the target presentation (the critical window) and four trials before the critical window. Regarding the proactive mode, patients with schizophrenia exhibited a specific decrease in frontal midline theta power during the critical window before a miss compared to a correct detection. In contrast, the contingent negative variation amplitude was altered regardless of the response type, four trials before the critical window. Regarding the reactive mode, a reduced P3 amplitude was revealed later before a miss than a correct detection with differences apparent only two trials before the critical window in patients with schizophrenia, whereas it was observable up to four trials prior in healthy controls. Moreover, only the P3 amplitude reduction in patients with schizophrenia predicted the miss rate and was anti-correlated with the clinical symptoms. Thus, our results revealed a specific impairment of the proactive goal-updating process before an error and an altered implementation of the endogenous proactive mode engagement regardless of the response type. The results also highlighted the strong relationship between the disrupted reactive mode and the increased rate of attentional errors and severity of the clinical symptoms of schizophrenia.

Effects of nocturnal railway noise on sleep fragmentation in young and middle-aged subjects as a function of type of train and sound level.

Due to undisputable effects of noise on sleep structure, especially in terms of sleep fragmentation, the expected development of railway transportation in the next few years might represent a potential risk factor for people living alongside the rail tracks. The aim of this study was to compare the effects of different types of train (freight, automotive, passenger) on arousal from sleep and to determine any differential impact as a function of sound level and age. Twenty young (16 women, 4 men; 25.8 years+/-2.6) and 18 middle-aged (15 women, 3 men; 52.2 years+/-2.5) healthy subjects participated in three whole-night polysomnographic recordings including one control night (35 dBA), and two noisy nights with equivalent noise levels of 40 or 50 dB(A), respectively. Arousal responsiveness increased with sound level. It was the highest in S2 and the lowest in REM sleep. Micro-arousals (3-10 s) occurred at a rate of 25-30%, irrespective of the type of train. Awakenings (>10 s) were produced more frequently by freight train than by automotive and passenger trains. Normal age-related changes in sleep were observed, but they were not aggravated by railway noise, thus questioning whether older persons are less sensitive to noise during sleep. These evidences led to the conclusion that microscopic detection of sleep fragmentation may provide advantageous information on sleep disturbances caused by environmental noises.

Combined effects of noise and shift work on fatigue as a function of age.

The study was conducted to analyse possible interactions between noise and shift work, and fatigue as a function of age. In a large questionnaire survey, we assessed personal and environmental risk factors related to fatigue. Noise exposure at work (L(Aeq, 8hr)) was measured with personal noise dosimetry. The sample included 254 day and shift workers, and was divided into 2 age groups (<40- and >40-year-olds). Noise exposure had a main effect on fatigue. The highest noise exposure resulted in an increase in the fatigue level of older shift workers. The quantity of sleep mainly depended on the type of shift and age. Our data suggest that the most important factor generating fatigue could be related to industrial noise exposure, a factor which seems to aggravate work-related fatigue generated in a synergic manner by shift work and ageing. Senior workers should be prevented from cumulating those occupational stressors.

Visual expertise for print in schizophrenia: Analysis of the N170 component.

Reading deficits have been reported for patients suffering from schizophrenia namely, specific phonological processing deficits. Phonological processing skills are crucial in the learning-to-read process as they are necessary to develop visual expertise for print, which reflects the neural specialization for print. The present study is the first to test visual expertise for print in patients suffering from schizophrenia by measuring the N170 component. Patients and pair-matched healthy control participants performed a lexical decision task, in which words and symbols were presented. As expected, larger N170 amplitudes to word than to control stimuli were observed at the left occipito-temporal site PO7 but not at the PO8. More importantly, the modulation of the N170 as a function of the stimulus and hemisphere did not vary between patients and controls. This result suggests preserved visual expertise for print processing in patients suffering from schizophrenia.

Evidence of impaired proactive control under positive affect.

If it can be assumed that positive affect modulates cognitive control, the underlying mechanisms remain unclear. The main aim of this study was to investigate how positive affect influences proactive and reactive modes of control and to explore the temporal dynamic of this influence, in terms of its transient and/or sustained effects. We used the AX-continuous performance task, combined with event-related potentials (ERP) recording. The results showed that positive affect impaired proactive control. More specifically, response preparation was weaker, as highlighted by a decreased contingent negative variation (CNV), prior to the target. As a consequence, conflict detection, as reflected by the N2 component, was decreased under positive affect. The P3a, associated with conflict resolution, remained unaffected by positive emotion, suggesting a lack of reactive control modulation. These effects were diffuse and did not appear on a transient timescale, highlighting the importance of positive emotion's time course for how it influences cognitive control processes.

Sustaining attention to simple visual tasks: a central deficit in schizophrenia? A systematic review.

Impairments in sustained attention, that is, the ability to achieve and maintain the focus of cognitive activity on a given stimulation source or task, have been described as central to schizophrenia. Today, sustained attention deficit is still considered as a hallmark of schizophrenia. Nevertheless, current findings on this topic are not consistent. To clarify these findings, we attempt to put these results into perspective according to the type of assessment (i.e., overall and over time assessment), the participants' characteristics (i.e., clinical and demographic characteristics), and the paradigms (i.e., traditionally formatted tasks, go/no-go tasks, and the sustained attention task) and measures used. Two types of assessment lead to opposite findings; they do not evaluate sustained attention the same way. Studies using overall assessments of sustained attention ability tend to reveal a deficit, whereas studies using over time assessments do not. Therefore, further research is needed to investigate the underlying cognitive control mechanisms of changes in sustained attention in schizophrenia.

Differentiating Motivational from Affective Influence of Performance-contingent Reward on Cognitive Control: The Wanting Component Enhances Both Proactive and Reactive Control.

Positive affect strongly modulates goal-directed behaviors and cognitive control mechanisms. It often results from the presence of a pleasant stimulus in the environment, whether that stimulus appears unpredictably or as a consequence of a particular behavior. The influence of positive affect linked to a random pleasant stimulus differs from the influence of positive affect resulting from performance-contingent pleasant stimuli. However, the mechanisms by which the performance contingency of pleasant stimuli modulates the influence of positive affect on cognitive control mechanisms have not been elucidated. Here, we tested the hypothesis that these differentiated effects are the consequence of the activation of the motivational "wanting" component specifically under performance contingency conditions. To that end, we directly compared the effects on cognitive control of pleasant stimuli (a monetary reward) attributed in a performance contingent manner, and of random pleasant stimuli (positive picture) not related to performance, during an AX-CPT task. Both proactive and reactive modes of control were increased specifically by performance contingency, as reflected by faster reaction times and larger amplitude of the CNV and P3a components. Our findings advance our understanding of the respective effects of affect and motivation, which is of special interest regarding alterations of emotion-motivation interaction found in several psychopathological disorders.

Sustained attention ability in schizophrenia: Investigation of conflict monitoring mechanisms.

OBJECTIVE: The main goal of the current study was to assess, with a time-on-task approach, sustained attention ability in schizophrenia, and to investigate conflict monitoring underlying this ability. METHODS: Behavioral and event-related potentials data (N2 and P3a amplitudes) were recorded in a long-lasting sustained attention Go/NoGo task (sustained attention to response task, SART), over a period of 30min, in 29 patients with schizophrenia and 29 pair-matched healthy subjects. RESULTS: Our results revealed spared sustained attention ability in patients throughout the task. Impairment of conflict detection (N2) in patients was particularly significant at the end of the task. Furthermore, both schizophrenia and healthy subjects exhibited a decline in conflict detection from the beginning to the middle of the task. Whereas controls' conflict detection recovered in the last part of the task, patients' did not, suggesting a deficit in recovery processes reflecting a lack of additional resources sustained attention Go/NoGo task. Conflict resolution (P3a) was preserved throughout the task in both groups. CONCLUSIONS: Conflict monitoring processes are increasingly impaired in schizophrenia during a long-lasting sustained attention Go/NoGo task. SIGNIFICANCE: This impairment at the end of the task may rely on deficit in recovery processes, rather than a deficit in conflict detection per se in schizophrenia.

The effects of age on visual expertise for print.

Progressive visual processing decline is a known factor in aging. The present study investigates the evolution of visual expertise for printed stimuli with aging. Fifty-five participants of increasing age (20-30, 40-50, 60-70, 75-85years old) were recruited. Behavioral and EEG data were collected during a lexical decision task, in which words and symbol strings were presented. Analyses of EEG data focused mainly on three major points: visual expertise for print, automatization of the expertise and differences in attentional demand between the processing of words and symbols. Results indicated a preservation of visual expertise with age, with larger N170 amplitude for words than for symbols. Moreover, a decrease in stimulus processing speed was observed as a function of age. No difference in attentional demand as a function of stimulus was observed.