Editorial: Neural mechanisms of impulsivity and compulsivity and their clinical and therapeutic corollaries
Charidimos Tzagarakis- 1Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
- 2Organization Against Drugs (OKANA), Athens, Greece
Editorial on the Research Topic
Neural mechanisms of impulsivity and compulsivity and their clinical and therapeutic corollaries
Anyone paying attention to the evolution of diagnostic (DSM-5, ICD-11) and research (RDoC- Insel et al., 2010) criteria for psychopathology in the past decade will observe an effort by clinicians and basic scientists alike to redefine our approach to psychopathology in a way that incorporates ever accumulating results from basic and clinical neuroscience and allows for novel and useful questions about diagnosis and treatment to be posed. In this process, the concepts of impulsivity and compulsivity are emerging as particularly relevant constructs (Robbins et al., 2012). The former tends to refer to styles of acting and making decisions with limited foresight and a proneness to errors (Tzagarakis et al., 2019), whilst the latter marks, in contrast, a behavioral “stickiness” with an abnormal perseveration on actions and strategies that are often maladaptive (Luigjes et al., 2019; Muela et al., 2022). Crucially, impulsivity and compulsivity can sometimes be perceived to mutually reinforce a vicious cycle in a number of conditions, such as gambling (Bowden-Jones et al., 2022) and, possibly, eating disorders, where both traits can co-occur (Howard et al., 2020). This observation and the questions it inevitably generates regarding possible shared or closely interrelated neurophysiological mechanisms (Belin et al., 2008) are at the core of this Research Topic. We were therefore happy to see submissions that were diverse in the methodology used and research paths pursued, but ultimately also highlighted striking physiological commonalities.
In two papers submitted in tandem (Scaife et al.; Braeutigam et al.), a group from the University of Oxford present results from a pioneering study of the treatment of severe anorexia nervosa using Deep Brain Stimulation (DBS) with electrodes implanted bilaterally in the Nucleus Accumbens. Only some of the seven participants in the study responded to DBS in what highlights future challenges that need to be addressed in order to define the place of this treatment modality in the management of severe eating disorders. In particular, factors such as electrode localization, prognostic patient profiles and their interaction will all need to be clarified in future work with larger cohorts. However, the study's design, including blind on vs. off DBS phases, detailed psychometrics and crucially, the longitudinal collection of neural data in the form of Magnetoencephalography (MEG) (Braeutigam et al.) sets a very useful reference point for the field and already offers tantalizing clues regarding the role of compulsivity in the pathophysiology of restrictive eating disorders, as there are indications of a correlation between response to treatment and pre-existing OCD. The use of MEG highlights the ever increasing usefulness of human electrophysiology in providing quality neural data that can drive hypothesis formation and testing in the realm of clinical research.
Using different techniques, but here too tackling a disease process where compulsive behavior is prominent. Hasuzawa et al. report on the resting state BOLD fluctuations (fractional amplitude of low frequency fluctuations—fALFFs) of a cohort of OCD patients vs. healthy controls, in relation to their performance in the Iowa Gambling Task, a neuropsychological test sensitive to pathological decision styles, where participants attempt to maximize long-term value accumulated by selecting cards from decks with different discounting profiles. Much like with the stimulated Accumbens in the anorexia studies, the Ventral Striatum seems to take center stage again, with higher putamen signal for the patient cohort compared to controls and a possible association to abnormally high sensitivity to Response Prediction Errors.
Finally, further adding to our insights into impulsivity/compulsivity, comes a non-human study of the effects of global cerebral ischemia on the neurochemistry and associated impulsive behavior of rats, by Morin et al. The Nucleus Accumbens is again implicated with Dopamine neurotransmission shown to be negatively affected. This does not however result in an increase in impulsive discounting, but rather has effects on the animals' motor behavior which may be associated with impulsive action. This dissociation of impulsive choice and impulsive action highlights the need to continue the exploration of the structure of the impulsivity and compulsivity constructs.
In their individual diversity and originality but also their striking commonalities, the papers in this Research Topic constitute significant contributions both to their specific respective fields and, at the same time, to the emerging understanding of the neurobiology and pathophysiology of the impulsivity/compulsivity dimension.
Author contributions
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Conflict of interest
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References
Belin, D., Mar, A. C., Dalley, J. W., Robbins, T. W., and Everitt, B. J. (2008). High impulsivity predicts the switch to compulsive cocaine-taking. Science 320, 1352–1355. doi: 10.1126/science.1158136
Bowden-Jones, H., Hook, R. W., Grant, J. E., Ioannidis, K., Corazza, O., Fineberg, N. A., et al. (2022). Gambling disorder in the UK: key research priorities and the urgent need for independent research funding. Lancet Psychiatry 9, 321–329. doi: 10.1016/S2215-0366(21)00356-4
Howard, M., Gregertsen, E. C., Hindocha, C., and Serpell, L. (2020). Impulsivity and compulsivity in anorexia and bulimia nervosa: a systematic review. Psychiatry Res. 293, 113354. doi: 10.1016/j.psychres.2020.113354
Insel, T., Cuthbert, B., Garvey, M., Heinssen, R., Pine, D. S., Quinn, K., et al. (2010). Research domain criteria (RDoC): toward a new classification framework for research on mental disorders. Am. J. Psychiatry 167, 748–751. doi: 10.1176/appi.ajp.2010.09091379
Luigjes, J., Lorenzetti, V., Haan, S., de Youssef, G. J., Murawski, C., Sjoerds, Z., et al. (2019). Defining compulsive behavior. Neuropsychol. Rev. 29, 4–13. doi: 10.1007/s11065-019-09404-9
Muela, I., Navas, J. F., Ventura-Lucena, J. M., and Perales, J. C. (2022). How to pin a compulsive behavior down: a systematic review and conceptual synthesis of compulsivity-sensitive items in measures of behavioral addiction. Addict. Behav. 134, 107410. doi: 10.1016/j.addbeh.2022.107410
Robbins, T. W., Gillan, C. M., Smith, D. G., de Wit, S., and Ersche, K. D. (2012). Neurocognitive endophenotypes of impulsivity and compulsivity: towards dimensional psychiatry. Trends Cogn. Sci. 16, 81–91. doi: 10.1016/j.tics.2011.11.009
Keywords: impulsivity, compulsivity, Ventral Striatum, Deep Brain Stimulation (DBS), Iowa Gambling Task (IGT), Nucleus Accumbens, global cerebral ischemia (GCI)
Citation: Tzagarakis C (2022) Editorial: Neural mechanisms of impulsivity and compulsivity and their clinical and therapeutic corollaries. Front. Behav. Neurosci. 16:991267. doi: 10.3389/fnbeh.2022.991267
Received: 11 July 2022; Accepted: 15 July 2022;
Published: 11 August 2022.
Edited and reviewed by: Liana Fattore, CNR Neuroscience Institute (IN), Italy
Copyright © 2022 Tzagarakis. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Charidimos Tzagarakis, haristz@umn.edu