Electrophysiological indices of altered working memory processes in long‐term ecstasy users

Nulsen, Claire; Fox, Allison M.; Hammond, Geoffrey R.

doi:10.1002/hup.1231

Cited by 12 publications

(8 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The finding of ecstasy users showing a durable abnormality in this ERP component exemplifies how EEG is a much more sensitive measure of cognitive impairment than behavioural measures alone. This point is further elucidated by Nulsen et al (2011) wherein ecstasy users displayed alternative patterns of activity in ERPs compared to drug naïve and polydrug controls in short term and working memory tasks, despite no significant behavioural differences.…”

Section: Eeg Studies In Ecstasy Usersmentioning

confidence: 90%

Electrophysiological indices of response inhibition in human polydrug users

et al. 2013

View full text Add to dashboard Cite

Previous research in ecstasy users suggests impairment of various executive functions. In general, the executive function of response inhibition appears unaffected by ecstasy use. Nonetheless, it remains a possibility that cognitive tasks alone are not sensitive enough to pick up subtle changes in function. The current study sought to investigate behavioural measures of response inhibition and their electrophysiological correlates in drug users. Twenty ecstasy polydrug users, 20 non-ecstasy polydrug users and 20 drug naïve controls were recruited. Participants completed questionnaires about their background drug use, sleep quality, fluid intelligence and mood state. Each individual also completed a Go/NoGo response inhibition task whilst electroencephalography (EEG) measures were recorded. Analysis of variance (ANOVA) revealed that there were no between-group differences on the behavioural measure of response inhibition. Multivariate analysis of variance (MANOVA) revealed no main effect of group across midline electrodes for the P3, N2 and P2 components. Univariate ANOVA revealed significant between-group differences in the P2 component with the ecstasy user group having a significantly higher mean amplitude than drug naïve controls at two midline frontal electrodes: at Fz and significantly higher mean amplitude than both control groups at FCz. The present study provides evidence of atypical early processing in ecstasy users that is suggestive of compensatory mechanisms ameliorating any behavioural differences.

show abstract

Section: Eeg Studies In Ecstasy Usersmentioning

confidence: 90%

Electrophysiological indices of response inhibition in human polydrug users

et al. 2013

View full text Add to dashboard Cite

show abstract

“…The remaining n = 11 (35%) brain imaging studies in our systematic review reported worse WM performance in SUD compared to controls and altered neural processes ( Bava et al, 2010 ; Moeller et al, 2010 ; Smith et al, 2010 ; Nulsen et al, 2011 ; Cservenka et al, 2012 ; Marvel et al, 2012 ; Fitzpatrick and Crowe, 2013 ; Ozsoy et al, 2013 ; Falcone et al, 2014 ; Claus and Hendershot, 2015 ; Liang et al, 2016 ). In conjunction with worse WM performance, structural studies demonstrated reduced fractional anisotropy (FA) in PFC WM networks and higher FA in visual networks that may be linked to cognitive biases in alcohol and marijuana-using adolescents ( Bava et al, 2010 ).…”

Section: Substance Use Disorders Working Memory and Cognitive Controlmentioning

confidence: 98%

The Role of Working Memory for Cognitive Control in Anorexia Nervosa versus Substance Use Disorder

et al. 2017

View full text Add to dashboard Cite

Prefrontal cortex executive functions, such as working memory (WM) interact with limbic processes to foster impulse control. Such an interaction is referred to in a growing body of publications by terms such as cognitive control, cognitive inhibition, affect regulation, self-regulation, top-down control, and cognitive–emotion interaction. The rising trend of research into cognitive control of impulsivity, using various related terms reflects the importance of research into impulse control, as failure to employ cognitions optimally may eventually result in mental disorder. Against this background, we take a novel approach using an impulse control spectrum model – where anorexia nervosa (AN) and substance use disorder (SUD) are at opposite extremes – to examine the role of WM for cognitive control. With this aim, we first summarize WM processes in the healthy brain in order to frame a systematic review of the neuropsychological, neural and genetic findings of AN and SUD. In our systematic review of WM/cognitive control, we found n = 15 studies of AN with a total of n = 582 AN and n = 365 HC participants; and n = 93 studies of SUD with n = 9106 SUD and n = 3028 HC participants. In particular, we consider how WM load/capacity may support the neural process of excessive epistemic foraging (cognitive sampling of the environment to test predictions about the world) in AN that reduces distraction from salient stimuli. We also consider the link between WM and cognitive control in people with SUD who are prone to ‘jumping to conclusions’ and reduced epistemic foraging. Finally, in light of our review, we consider WM training as a novel research tool and an adjunct to enhance treatment that improves cognitive control of impulsivity.

show abstract

“…Several recent evoked response potential studies have shown an association between the task performance deficits of abstinent Ecstasy/MDMA users and altered patterns of brain activity (Roberts et al ., ; Burgess et al ., ; Nulsen et al ., ). In a large neuroimaging study, Kish et al .…”

Section: New Psychobiological Deficitsmentioning

confidence: 97%

MDMA is certainly damaging after 25 years of empirical research: a reply and refutation of Doblinet al. (2014)

Parrott

2014

Hum. Psychopharmacol Clin Exp

View full text Add to dashboard Cite

Human Psychopharmacology recently published my review into the increase in empirical knowledge about the human psychobiology of MDMA over the past 25 years (Parrott, 2013a). Deficits have been demonstrated in retrospective memory, prospective memory, higher cognition, complex visual processing, sleep architecture, sleep apnoea, pain, neurohormonal activity, and psychiatric status. Neuroimaging studies have shown serotonergic deficits, which are associated with lifetime Ecstasy/MDMA usage, and degree of neurocognitive impairment. Basic psychological skills remain intact. Ecstasy/MDMA use by pregnant mothers leads to psychomotor impairments in the children. Hence, the damaging effects of Ecstasy/MDMA were far more widespread than was realized a few years ago. In their critique of my review, Doblin et al. (2014) argued that my review contained misstatements, omitted contrary findings, and recited dated misconceptions. In this reply, I have answered all the points they raised. I have been able to refute each of their criticisms by citing the relevant empirical data, since many of their points were based on inaccurate summaries of the actual research findings. Doblin and colleagues are proponents of the use of MDMA for drug-assisted psychotherapy, and their strongest criticisms were focused on my concerns about this proposal. However, again all the issues I raised were based on sound empirical evidence or theoretical understanding. Indeed I would recommend potentially far safer co-drugs such as D-cycloserine or oxytocin. In summary, MDMA can induce a wide range of neuropsychobiological changes, many of which are damaging to humans.

show abstract

Electrophysiological indices of altered working memory processes in long‐term ecstasy users

Cited by 12 publications

References 41 publications

Electrophysiological indices of response inhibition in human polydrug users

Electrophysiological indices of response inhibition in human polydrug users

The Role of Working Memory for Cognitive Control in Anorexia Nervosa versus Substance Use Disorder

MDMA is certainly damaging after 25 years of empirical research: a reply and refutation of Doblinet al. (2014)

Contact Info

Product

Resources

About