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519 Quantitative EEG reveals changes in human brain function associated with MDMA (“ecstasy”) use
200
Abstracts
/International
Journal
of Psychophysiology300
quency percentages of the abnormal behaviours, even tough they changed with regard to some formal characteristics. We found significant differences between the two groups (i.e., autistic vs. non-autistic children) regarding the performance on the executive function tasks. DISCUSSION. The various abnormal behaviours seemed to share some common features such as overselectivity, rigidity, and perseveration. These features suggest a deficit of the executive functions defined as the set of abilities involved to maintaining an appropriate problem-solving framework. Nonetheless, the role of the executive function deficits in AD are not clear both for the undefined causal links between executive dysfunction and impaired social interaction, and the presence of executive dysfunction in psychopathologic disorders other than autism.
518 SLEEP IN AUTISM M. Elia, R. Ferri, S.A. Musumeci, S. Panerai, J.C. Grubar, T. r>Bertrand, G. Miano and M. Bottitta Dept. Of Neurology, Oasi Institute, Troina, Italy A sleep polygraphic study (EOG, EEG, EMG) was performed on 17 male children and adolescents with autistic disorder and mental retardation, and on 6 normal age- and sex-matched male controls. Although sleep structure and density of rapid eye movements @EMS) resulted almos 9 not different in the two groups of subjects, some parameters such as time in bed (TIB), sleep period time (SPT), total sleep time (TST), and sleep efficiency index (SE11 were significantly lower in autistic subjects than in controls. Density of mental twitches resulted significantly higher in subjects with autism. A negative correlation was found between total scoring of passing items of psychoeducational profile-revised (PEP-R) and some sleep parameters: sleep onset latency (SOL), wakefulness after sleep onset (WASO), stage shifts (SSh), first REM latency (FRL). Our results suggest the existence of a sleep pattern in autistic patients which is different from that observed in mentally retarded patients. Furthermore, these preliminary data indicate that sleep polygraphy is in some way correlated with some psychological indices generally used in diagnosing autism; then it might represent a objective neurophysiological tool, not only in a diagnostic, but also in a prognostic perspective in this condition.
519 QUANTITATIVE EEG REVEALS CHANGES IN HUMAN BRAIN FUNCTION ASSOCIATED WITH mm4 (“ECSTASY’? USE Richard Dafters and Caroline Bouquet Psychology Dept., University of Glasgow, Adam Smith Building, Bute Gardens, Glasgow, UK
(1998)
95-271
Despite widespread fears and speculation about long-term neurotoxic consequences of recreational use of the substituted amphetamines, such as methylenedioxy-methamphetamine (MDMA or “Ecstasy”), there has been little evidence to date of physiological signs of abnormal brain function following chronic use in humans, although there have been isolated reports of cognitive and mood changes. An additional problem is that in previous studies MDMA users were compared with non-drug using controls, despite the fact that most MDMA users are polydrug users. In the study reported here, a 128. channel geodesic sensor net (Electrical Geodesics Inc.) was used to obtain quantitative PEG data in the resting, eyesclosed condition from a sample of 24 young (18-24 years), long-term recreational drug users. The subjects consisted of 12 high MDMA users (drug taken on at least 20 occasions) and 12 low MDMA users who were matched for IQ, educational background, gender, and use of other common recreational drugs, such as alcohol, nicotine, cannabis, amphetamine and LSD. The dense-mapping sensor array we employed approaches the theoretical maximum for scalp spatial resolution and therefore allows more accurate localisation of regional EEG power differences. A fast Fourier analysis technique was used to calculate mean power in 4 frequency bands - delta (2-4Hz), theta (5-7Hz), alpha (8-12Hz), beta (13-22Hz) in homologous groups of electrodes located in the left-anterior (Ten-Twenty positions - F7, F3, Fpl), right-anterior (positions - F4, F8, Fp2), left-posterior (positions - 01, T5, P3), and right posterior (positions - 02, P4, T6) quadrants of the scalp. Tests of mood (Beck’s Depression Inventory, BDI, and Positive and Negative Affect Scales, PANAS), memory (Rivermead Memory Test - immediate and delayed) and perseveration (Behavioural Assessment of the Dysexecutive Syndrome - Rule Shift Cards test, BADS) were also administered. Multiple regression analysis revealed significant positive correlations between MDMA use in the previous year and mean power in the alpha (8-12Hz) frequency range (P < .05). The correlation between MDMA use and alpha power was also significant for left-anterior, left-posterior, and right-posterior quadrants considered separately, but not for the rightanterior quadrant. An index of frontal asymmetry in alpha power also revealed an MDMA-related shift towards left frontal alpha dominance. MDMA use did not correlate with EEG power in any other frequency range or with any of the mood scores or memoty scores, but did correlate negatively with performance on the Rule Shift Cards test of perseveration. MDMA use did not correlate with use of any other drug, and no other drug correlated with changes in spectral power or performance on the perseveration test. The results, which are the first to report quantative electrophysiological changes in humans related to chronic MDMA use, are interpreted in light of MDMA’s serotonergic neurotoxicity and its postulated effects on memory and impulsivity, and in relation to changes in level and distribution of alpha EEG power in aging, depression and dementia.
Abstracts
/International
Journal
of Psychophysiology300
quency percentages of the abnormal behaviours, even tough they changed with regard to some formal characteristics. We found significant differences between the two groups (i.e., autistic vs. non-autistic children) regarding the performance on the executive function tasks. DISCUSSION. The various abnormal behaviours seemed to share some common features such as overselectivity, rigidity, and perseveration. These features suggest a deficit of the executive functions defined as the set of abilities involved to maintaining an appropriate problem-solving framework. Nonetheless, the role of the executive function deficits in AD are not clear both for the undefined causal links between executive dysfunction and impaired social interaction, and the presence of executive dysfunction in psychopathologic disorders other than autism.
518 SLEEP IN AUTISM M. Elia, R. Ferri, S.A. Musumeci, S. Panerai, J.C. Grubar, T. r>Bertrand, G. Miano and M. Bottitta Dept. Of Neurology, Oasi Institute, Troina, Italy A sleep polygraphic study (EOG, EEG, EMG) was performed on 17 male children and adolescents with autistic disorder and mental retardation, and on 6 normal age- and sex-matched male controls. Although sleep structure and density of rapid eye movements @EMS) resulted almos 9 not different in the two groups of subjects, some parameters such as time in bed (TIB), sleep period time (SPT), total sleep time (TST), and sleep efficiency index (SE11 were significantly lower in autistic subjects than in controls. Density of mental twitches resulted significantly higher in subjects with autism. A negative correlation was found between total scoring of passing items of psychoeducational profile-revised (PEP-R) and some sleep parameters: sleep onset latency (SOL), wakefulness after sleep onset (WASO), stage shifts (SSh), first REM latency (FRL). Our results suggest the existence of a sleep pattern in autistic patients which is different from that observed in mentally retarded patients. Furthermore, these preliminary data indicate that sleep polygraphy is in some way correlated with some psychological indices generally used in diagnosing autism; then it might represent a objective neurophysiological tool, not only in a diagnostic, but also in a prognostic perspective in this condition.
519 QUANTITATIVE EEG REVEALS CHANGES IN HUMAN BRAIN FUNCTION ASSOCIATED WITH mm4 (“ECSTASY’? USE Richard Dafters and Caroline Bouquet Psychology Dept., University of Glasgow, Adam Smith Building, Bute Gardens, Glasgow, UK
(1998)
95-271
Despite widespread fears and speculation about long-term neurotoxic consequences of recreational use of the substituted amphetamines, such as methylenedioxy-methamphetamine (MDMA or “Ecstasy”), there has been little evidence to date of physiological signs of abnormal brain function following chronic use in humans, although there have been isolated reports of cognitive and mood changes. An additional problem is that in previous studies MDMA users were compared with non-drug using controls, despite the fact that most MDMA users are polydrug users. In the study reported here, a 128. channel geodesic sensor net (Electrical Geodesics Inc.) was used to obtain quantitative PEG data in the resting, eyesclosed condition from a sample of 24 young (18-24 years), long-term recreational drug users. The subjects consisted of 12 high MDMA users (drug taken on at least 20 occasions) and 12 low MDMA users who were matched for IQ, educational background, gender, and use of other common recreational drugs, such as alcohol, nicotine, cannabis, amphetamine and LSD. The dense-mapping sensor array we employed approaches the theoretical maximum for scalp spatial resolution and therefore allows more accurate localisation of regional EEG power differences. A fast Fourier analysis technique was used to calculate mean power in 4 frequency bands - delta (2-4Hz), theta (5-7Hz), alpha (8-12Hz), beta (13-22Hz) in homologous groups of electrodes located in the left-anterior (Ten-Twenty positions - F7, F3, Fpl), right-anterior (positions - F4, F8, Fp2), left-posterior (positions - 01, T5, P3), and right posterior (positions - 02, P4, T6) quadrants of the scalp. Tests of mood (Beck’s Depression Inventory, BDI, and Positive and Negative Affect Scales, PANAS), memory (Rivermead Memory Test - immediate and delayed) and perseveration (Behavioural Assessment of the Dysexecutive Syndrome - Rule Shift Cards test, BADS) were also administered. Multiple regression analysis revealed significant positive correlations between MDMA use in the previous year and mean power in the alpha (8-12Hz) frequency range (P < .05). The correlation between MDMA use and alpha power was also significant for left-anterior, left-posterior, and right-posterior quadrants considered separately, but not for the rightanterior quadrant. An index of frontal asymmetry in alpha power also revealed an MDMA-related shift towards left frontal alpha dominance. MDMA use did not correlate with EEG power in any other frequency range or with any of the mood scores or memoty scores, but did correlate negatively with performance on the Rule Shift Cards test of perseveration. MDMA use did not correlate with use of any other drug, and no other drug correlated with changes in spectral power or performance on the perseveration test. The results, which are the first to report quantative electrophysiological changes in humans related to chronic MDMA use, are interpreted in light of MDMA’s serotonergic neurotoxicity and its postulated effects on memory and impulsivity, and in relation to changes in level and distribution of alpha EEG power in aging, depression and dementia.