Prospective Memory, Sustained Attention and Response Inhibition in Poly-Substance Users Stable on Methadone Maintenance Treatment

Abstract

Background: Prospective memory and response inhibition are interrelated constructs, though studied separately in the drug addiction literature. Also, although sustained attention underlies response inhibition, its role in the relation between these functions has been largely neglected. The limited research on the cognitive effects of methadone-maintenance treatment (MMT) further stresses the importance of investigating these effects. Objective: Therefore, the current study focused on possible effects of MMT combined with long-term drug abuse on all these functions. Thirty five long term opiate/poly-substance users in MMT and thirty four drug-free controls were screened for socioeconomic status, anxiety, depression and general, non-verbal intelligence and then tested on a self-report measure of prospective memory and on the Go/No-Go task. Results: Compared to controls, the MMT group scored worse in all functions assessed. Prospective memory scores were also negatively related to Go/NoGo accuracy scores. Conclusion: As predicted, (a) the MMT participants show impairments in prospective memory, sustained attention and response inhibition and (b) prospective memory, response inhibition and sustained attention are related constructs. The results of this study could inform current rehabilitation and relapse prevention cognitive training practices.

Keywords:

• Prospective memory
• executive functioning
• response inhibition
• sustained attention
• Go/No go task
• poly-substance users
• methadone

Acknowledgments

We are grateful to Dr. Tziraki Maria for her invaluable assistance with the theoretical frameworks presented in this paper, and to Dr. Chatzimpiros Vasilis who moderated this paper, both of whom improved the manuscript significantly. Any errors are our own and should not tarnish the reputations of these esteemed professionals. We would also like to express our gratitude to the participants of this study, whose contribution was invaluable.

Declaration of interest

In accordance with Taylor & Francis policy and my ethical obligation as a researcher, I am reporting that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome.

Data availability statement

The data that support the findings of this study are openly available in the data.world repository, at https://data.world/adhara/prospective-memory-response-inhibition-methadone under the title “Prospective Memory, response inhibition, methadone”.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.