To ascertain whether variations in central dopaminergic transmission can differentially affect mo... more To ascertain whether variations in central dopaminergic transmission can differentially affect motor and cognitive processing, we studied the effects of apomorphine (APO) in 9 patients with Parkinson's disease (PD). The UPDRS motor scores and auditory event-related potentials (ERPs) obtained in the 'odd-ball' (OB) and in the 'covert orientation of attention' (COA) tasks were studied in the 'off' and in the 'on' state after an injection of APO. Although APO injection improved patients' motor status, it induced a significant increase in the latencies of the P2 and P3 ERP components in the OB. In the COA task, right-hand reaction times (RTs) were markedly shortened in the 'on' state while left hand RTs remained unchanged. The contrasting effects of dopaminergic stimulation on the motor performance and on some aspects of cognitive processing suggest the existence of complex interactions within pre- and postsynaptic brain dopamine receptors, and an intervention of segregated basal ganglia-prefrontal cortex loops in motor and cognitive behaviour.
ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive ... more ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive activities. Attentional processes play a fundamental role in those activities. An original conception of attention is outlined. In this view, attention is considered as responsible of managing of different cognitive processes. The interest of attentional impairment assessment with ERPs particularly in psychiatric disorders such as depression is underlined. This is illustrated by Buchsbaum M.S. et al. (1988) study. These authors recorded EPs, during a continuous performance test, in 3 groups of depressive patients under amoxapine, imipramine or placebo. Results showed in the amoxapine group and enhanced N120 amplitude in midline and right parietal cortex. In normal subjects, an amplitude increase in those areas usually reflects a selective attention effect. Behavioral performance was improved in the amoxapine group compared to that of patients who received imipramine or placebo. This impr...
ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive ... more ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive activities. Attentional processes play a fundamental role in those activities. An original conception of attention is outlined. In this view, attention is considered as responsible of managing of different cognitive processes. The interest of attentional impairment assessment with ERPs particularly in psychiatric disorders such as depression is underlined. This is illustrated by Buchsbaum M.S. et al. (1988) study. These authors recorded EPs, during a continuous performance test, in 3 groups of depressive patients under amoxapine, imipramine or placebo. Results showed in the amoxapine group and enhanced N120 amplitude in midline and right parietal cortex. In normal subjects, an amplitude increase in those areas usually reflects a selective attention effect. Behavioral performance was improved in the amoxapine group compared to that of patients who received imipramine or placebo. This improvement as soon as 48 h after drug administration could be related to the higher amoxapine affinity for serotonin S2 receptors.
Background: Many studies have shown the impact of acute aerobic exercises (AAE) on cognition in h... more Background: Many studies have shown the impact of acute aerobic exercises (AAE) on cognition in healthy adults or at a pre-dementia stage. Few studies, however, have explored the positive effects of AAE in moderate Alzheimer’s disease (ADM) patients. Objective: Evaluating the effect of AAE on cognitive functions in ADM patients. Methods: Overall, 79 (age: 69.62±0.99) ADM patients were recruited. Participants were divided into three groups according to the task: aerobic exercises done alone or combined with cognitive games presented on a screen, and a control group who performed a reading task. The aerobic exercise protocol consisted of a 20-min cycling exercise of moderate intensity, corresponding to 60%of the individual target maximal heart rate recorded in a 6-minute walking test. The participants’ cognition was monitored before and after the intervention using the Tower of Hanoi, Digit Span, and Stroop tasks. Results: After the exercise, the participants’ attention in both the ph...
This article reviews the findings of event-related potentials (ERP) in Parkinson's disease (P... more This article reviews the findings of event-related potentials (ERP) in Parkinson's disease (PD) published during the last 10 years. Basic principles and methods of ERP are briefly presented with particular regard to the auditory “odd-ball” paradigm almost uniquely employed for the ERP assessment in PD to date. The results of respective studies are overviewed and discussed with respect to three main axes: (1) The slowing down of cognitive processing in PD is reflected by the delays of N2 and P3 components of ERP which are more important in demented than in non-demented patients. The Nl component is delayed in demented patients with PD as well as in other dementias of presumed subcortical origin. (2) Various neuropsychological deficits observed in PD correlate with the delays of ERP evoking the implication of common subcortico-cortical cerebral mechanisms. (3) The variations of ERP under dopaminergic manipulation suggest conflicting effects of levodopa treatment on cognition, at l...
ObjectiveInsufficient sleep duration and quality has negative effects on athletic performance, in... more ObjectiveInsufficient sleep duration and quality has negative effects on athletic performance, injury susceptibility and athlete development. This study aimed to assess the sleep characteristics of professional Qatar Stars League (QSL) soccer players.MethodsIn a cross-sectional study, QSL players (n=111; 23.7±4.8 years) completed three questionnaires to screen sleep disorders: (1) Pittsburgh Sleep Quality Index (PSQI), (2) Insomnia Severity Index (ISI) and (3) Epworth Sleepiness Scale (ESS). Poor sleep quality was defined as PSQI≥5, excessive daytime sleepiness was defined by ESS>8 and insomnia was defined as ISI≥11.ResultsThe prevalence of poor sleep quality (PSQI≥5) was 68.5%, with subthreshold insomnia (ISI≥11) 27.0% and daytime sleepiness 22.5% (ESS>8). Sleep quality was positively associated with insomnia (r=0.42, p<0.001) and daytime sleepiness (r=0.23, p=0.018). Age, anthropometry, body composition and ethnicity were not associated with any of the reported sleep qual...
The aim of this study was to verify the hypothesis that hyperthermia represents a cognitive load ... more The aim of this study was to verify the hypothesis that hyperthermia represents a cognitive load limiting available resources for executing concurrent cognitive tasks. Electroencephalographic activity (EEG: alpha and theta power) was obtained in 10 hyperthermic participants in HOT (50°C, 50% RH) conditions and in a normothermic state in CON (25°C, 50% RH) conditions in counterbalanced order. In each trial, EEG was measured over the frontal lobe prior to task engagement (PRE) in each condition and during simple (One Touch Stockings of Cambridge, OTS-4) and complex (OTS-6) cognitive tasks. Core (39.5 ± 0.5 vs. 36.9 ± 0.2°C) and mean skin (39.06 ± 0.3 vs. 31.6 ± 0.6°C) temperatures were significantly higher in HOT than CON ( < 0.005). Theta power significantly increased with task demand ( = 0.017, η = 0.36) and was significantly higher in HOT than CON ( = 0.041, η = 0.39). The difference between HOT and CON was large (η = 0.40) and significant ( = 0.036) PRE, large (η = 0.20) but no...
To ascertain whether variations in central dopaminergic transmission can differentially affect mo... more To ascertain whether variations in central dopaminergic transmission can differentially affect motor and cognitive processing, we studied the effects of apomorphine (APO) in 9 patients with Parkinson's disease (PD). The UPDRS motor scores and auditory event-related potentials (ERPs) obtained in the 'odd-ball' (OB) and in the 'covert orientation of attention' (COA) tasks were studied in the 'off' and in the 'on' state after an injection of APO. Although APO injection improved patients' motor status, it induced a significant increase in the latencies of the P2 and P3 ERP components in the OB. In the COA task, right-hand reaction times (RTs) were markedly shortened in the 'on' state while left hand RTs remained unchanged. The contrasting effects of dopaminergic stimulation on the motor performance and on some aspects of cognitive processing suggest the existence of complex interactions within pre- and postsynaptic brain dopamine receptors, and an intervention of segregated basal ganglia-prefrontal cortex loops in motor and cognitive behaviour.
ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive ... more ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive activities. Attentional processes play a fundamental role in those activities. An original conception of attention is outlined. In this view, attention is considered as responsible of managing of different cognitive processes. The interest of attentional impairment assessment with ERPs particularly in psychiatric disorders such as depression is underlined. This is illustrated by Buchsbaum M.S. et al. (1988) study. These authors recorded EPs, during a continuous performance test, in 3 groups of depressive patients under amoxapine, imipramine or placebo. Results showed in the amoxapine group and enhanced N120 amplitude in midline and right parietal cortex. In normal subjects, an amplitude increase in those areas usually reflects a selective attention effect. Behavioral performance was improved in the amoxapine group compared to that of patients who received imipramine or placebo. This impr...
ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive ... more ERPs are described as a new dependent variable class allowing a dynamic exploration of cognitive activities. Attentional processes play a fundamental role in those activities. An original conception of attention is outlined. In this view, attention is considered as responsible of managing of different cognitive processes. The interest of attentional impairment assessment with ERPs particularly in psychiatric disorders such as depression is underlined. This is illustrated by Buchsbaum M.S. et al. (1988) study. These authors recorded EPs, during a continuous performance test, in 3 groups of depressive patients under amoxapine, imipramine or placebo. Results showed in the amoxapine group and enhanced N120 amplitude in midline and right parietal cortex. In normal subjects, an amplitude increase in those areas usually reflects a selective attention effect. Behavioral performance was improved in the amoxapine group compared to that of patients who received imipramine or placebo. This improvement as soon as 48 h after drug administration could be related to the higher amoxapine affinity for serotonin S2 receptors.
Background: Many studies have shown the impact of acute aerobic exercises (AAE) on cognition in h... more Background: Many studies have shown the impact of acute aerobic exercises (AAE) on cognition in healthy adults or at a pre-dementia stage. Few studies, however, have explored the positive effects of AAE in moderate Alzheimer’s disease (ADM) patients. Objective: Evaluating the effect of AAE on cognitive functions in ADM patients. Methods: Overall, 79 (age: 69.62±0.99) ADM patients were recruited. Participants were divided into three groups according to the task: aerobic exercises done alone or combined with cognitive games presented on a screen, and a control group who performed a reading task. The aerobic exercise protocol consisted of a 20-min cycling exercise of moderate intensity, corresponding to 60%of the individual target maximal heart rate recorded in a 6-minute walking test. The participants’ cognition was monitored before and after the intervention using the Tower of Hanoi, Digit Span, and Stroop tasks. Results: After the exercise, the participants’ attention in both the ph...
This article reviews the findings of event-related potentials (ERP) in Parkinson's disease (P... more This article reviews the findings of event-related potentials (ERP) in Parkinson's disease (PD) published during the last 10 years. Basic principles and methods of ERP are briefly presented with particular regard to the auditory “odd-ball” paradigm almost uniquely employed for the ERP assessment in PD to date. The results of respective studies are overviewed and discussed with respect to three main axes: (1) The slowing down of cognitive processing in PD is reflected by the delays of N2 and P3 components of ERP which are more important in demented than in non-demented patients. The Nl component is delayed in demented patients with PD as well as in other dementias of presumed subcortical origin. (2) Various neuropsychological deficits observed in PD correlate with the delays of ERP evoking the implication of common subcortico-cortical cerebral mechanisms. (3) The variations of ERP under dopaminergic manipulation suggest conflicting effects of levodopa treatment on cognition, at l...
ObjectiveInsufficient sleep duration and quality has negative effects on athletic performance, in... more ObjectiveInsufficient sleep duration and quality has negative effects on athletic performance, injury susceptibility and athlete development. This study aimed to assess the sleep characteristics of professional Qatar Stars League (QSL) soccer players.MethodsIn a cross-sectional study, QSL players (n=111; 23.7±4.8 years) completed three questionnaires to screen sleep disorders: (1) Pittsburgh Sleep Quality Index (PSQI), (2) Insomnia Severity Index (ISI) and (3) Epworth Sleepiness Scale (ESS). Poor sleep quality was defined as PSQI≥5, excessive daytime sleepiness was defined by ESS>8 and insomnia was defined as ISI≥11.ResultsThe prevalence of poor sleep quality (PSQI≥5) was 68.5%, with subthreshold insomnia (ISI≥11) 27.0% and daytime sleepiness 22.5% (ESS>8). Sleep quality was positively associated with insomnia (r=0.42, p<0.001) and daytime sleepiness (r=0.23, p=0.018). Age, anthropometry, body composition and ethnicity were not associated with any of the reported sleep qual...
The aim of this study was to verify the hypothesis that hyperthermia represents a cognitive load ... more The aim of this study was to verify the hypothesis that hyperthermia represents a cognitive load limiting available resources for executing concurrent cognitive tasks. Electroencephalographic activity (EEG: alpha and theta power) was obtained in 10 hyperthermic participants in HOT (50°C, 50% RH) conditions and in a normothermic state in CON (25°C, 50% RH) conditions in counterbalanced order. In each trial, EEG was measured over the frontal lobe prior to task engagement (PRE) in each condition and during simple (One Touch Stockings of Cambridge, OTS-4) and complex (OTS-6) cognitive tasks. Core (39.5 ± 0.5 vs. 36.9 ± 0.2°C) and mean skin (39.06 ± 0.3 vs. 31.6 ± 0.6°C) temperatures were significantly higher in HOT than CON ( < 0.005). Theta power significantly increased with task demand ( = 0.017, η = 0.36) and was significantly higher in HOT than CON ( = 0.041, η = 0.39). The difference between HOT and CON was large (η = 0.40) and significant ( = 0.036) PRE, large (η = 0.20) but no...
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