Neural Mechanisms of Attention Lapses in Adult ADHD

Study Overview
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Brief Summary
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ADHD is a common disorder, leading to a significant disability that often persists in adulthood. ADHD is characterized by attentional disturbances that are difficult to asses with standard neuropsychological tests. Attention tends to stall after a certain time of fatigue (i.e. an attention lapse). The aim of this study is to study the electroencephalographic (EEG) characteristics of these attention lapses in a sustained attention task, comparing ADHD patients with healthy subjects.

Detailed Description
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The main goal is to assess with EEG the timing of the attentional demobilization that precedes a sustained attention lapse in patients with ADHD. The secondary objectives are: 1 / To analyze impaired cognitive control mechanisms during lapses in patients with ADHD; 2 / Study the relationships between the deficits identified through EEG recording, clinical evaluations, and the subjective perception of daily difficulties; 3 / To measure the impact of the subjective attention state on the neuronal precursors of the attentional lapses; 4 / Evaluate the relation between propensity to wandering mind and attentional lapses.

Official Title
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Neural Mechanisms Underlying Attention Lapses in Adult Attention Deficit Disorder: Towards a Better Clinical Diagnosis

Conditions
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Attention Deficit Disorder, Hyperactivity Disorder

Intervention / Treatment
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* Other: Electroencephalography during sustained attention task.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of ADHD according to DSM-5 criteria by a psychiatrist with clinical experience with ADHD aged 18 to 60 having signed an informed consent able to understand the objectives and the risks related to the research For Healthy controls Absence of psychiatric disorder or neurological disease Matched in sex, age (± 2 years) and level of study (± 2 years) to each ADHD patient Exclusion criteria: treatment by Methylphenidate or amphetamine in the 3 months preceding the study treatment by a psychotropic drug other than antidepressant SSRI: anti-depressant non-SSRI, antipsychotic, mood stabilizer, benzodiazepine or hypnotic daily intake neurological pathology or neurological sequelae history of head trauma with loss of consciousness of more than 15 minutes Subject under the protection of justice Subject under guardianship, curatorship Subject in exclusion period (determined by previous or current study), Impossibility to give the subject enlightened information (subject in emergency situation, difficulties of comprehension of the subject (for example mental retardation, illiteracy, subject not including French ...)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Adult ADHD<br>Adult ADHD patients without current comorbidity and treatment. | Other: Electroencephalography during sustained attention task.<br>* The Continuous Temporal Expectancy Task (CTET) (O'Connell et al., 2009) is a very demanding discrimination task with sustained attention. It consists of the presentation on a computer screen of a visual pattern resembling a checkerboard that changes orientation at regular intervals of time. In this task the subject must respond (pressing a response button) to the appearance of rare target stimuli that have a longer duration (1120 ms) than non-target stimuli (800 ms). SART (Sustained Attention to Response Task) (Robertson et al., 1997) is a task of inhibition (Go / No-Go task) to evaluate the capacities of sustained attention. It consists in the successive and random presentation on a computer screen of the numbers from 1 to 9. In this task the subject must respond, by pressing a response button, to the appearance of all the numbers (very non-target stimuli frequent), with the exception of the number 3.<br>* Other names: SART (Sustained Attention to Response Task);|
| Healthy controls<br>Healthy controls without ADH, paired in age and gender. | Other: Electroencephalography during sustained attention task.<br>* The Continuous Temporal Expectancy Task (CTET) (O'Connell et al., 2009) is a very demanding discrimination task with sustained attention. It consists of the presentation on a computer screen of a visual pattern resembling a checkerboard that changes orientation at regular intervals of time. In this task the subject must respond (pressing a response button) to the appearance of rare target stimuli that have a longer duration (1120 ms) than non-target stimuli (800 ms). SART (Sustained Attention to Response Task) (Robertson et al., 1997) is a task of inhibition (Go / No-Go task) to evaluate the capacities of sustained attention. It consists in the successive and random presentation on a computer screen of the numbers from 1 to 9. In this task the subject must respond, by pressing a response button, to the appearance of all the numbers (very non-target stimuli frequent), with the exception of the number 3.<br>* Other names: SART (Sustained Attention to Response Task);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Spectral amplitude of the alpha band (8-14 Hz) to the quantitative EEG during the period up to 20 seconds before the successful trials vs. missed trials (lapse). | In healthy subjects, EEG changes, including increased parieto-occipital activity in the alphas frequency band (8-14Hz), have been observed 20 seconds before lapse (O'Connell et al., 2009). The analysis of the evoked potentials associated with the stimuli presented just before the occurrence of the target stimulus, reveals that the amplitude of the P300 on the 5 trials preceding the target to be detected is significantly lower before an omission (lapse) than before a correct detection. | During EEG realized after the inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CNV difference between missed and successful trials | Time course analysis of electrophysiological markers (EEG) before an attention lapse : amplitude of the evoked potentials | During EEG realized after the inclusion | 
| CNV difference between missed and successful trials | Time course analysis of electrophysiological markers (EEG) after a successful test: amplitude of the evoked potentials and theta power (intensity in μV). | During EEG realized after the inclusion | 
| Association between EEG lapses markers, neuropsychological measures of attention, clinical scales and subjective mindwandering | Regression and correlation analyzes involving electrophysiological markers associated with attentional lapses (see main objective) | During EEG realized after the inclusion | 
| Association between EEG lapses markers, neuropsychological measures of attention, clinical scales and subjective mindwandering | Regression and correlation analyzes involving electrophysiological markers associated with neuropsychological attention test scores (TAP) | During EEG realized after the inclusion | 
| Association between EEG lapses markers, neuropsychological measures of attention, clinical scales and subjective mindwandering | Regression and correlation analyzes involving electrophysiological markers associated with clinical scales (self-report ASRS and WFIRS) | During EEG realized after the inclusion | 
| Association between EEG lapses markers, neuropsychological measures of attention, clinical scales and subjective mindwandering | Regression and correlation analyzes involving electrophysiological markers associated with subjective measures of mind wandering (ad hoc questionnaire) | During EEG realized after the inclusion | 
| EEG lapse markers according attentional subjective state | Frequency of lapses of attentional lapses (evoked potentials P3a and CNV, theta power) (intensity in μV), according to the attentional state described by the subjects during the evaluations during the task | During EEG realized after the inclusion | 
| EEG lapse markers according attentional subjective state | amplitude electrophysiological markers (EEG) of attentional lapses (evoked potentials P3a and CNV, theta power) (intensity in μV), according to the attentional state described by the subjects during the evaluations during the task | During EEG realized after the inclusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Electroencephalography, Neurocognition, Attention deficit, Attention lapses