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Schifano F, Catalani V, Sharif S, Napoletano F, Corkery JM, Arillotta D, Fergus S, Vento A, Guirguis A. Benefits and Harms of 'Smart Drugs' (Nootropics) in Healthy Individuals. Drugs 2022; 82:633-647. [PMID: 35366192 DOI: 10.1007/s40265-022-01701-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2022] [Indexed: 12/14/2022]
Abstract
'Smart drugs' (also known as 'nootropics' and 'cognitive enhancers' [CEs]) are being used by healthy subjects (i.e. students and workers) typically to improve memory, attention, learning, executive functions and vigilance, hence the reference to a 'pharmaceutical cognitive doping behaviour'. While the efficacy of known CEs in individuals with memory or learning deficits is well known, their effect on non-impaired brains is still to be fully assessed. This paper aims to provide an overview on the prevalence of use; putative neuroenhancement benefits and possible harms relating to the intake of the most popular CEs (e.g. amphetamine-type stimulants, methylphenidate, donepezil, selegiline, modafinil, piracetam, benzodiazepine inverse agonists, and unifiram analogues) in healthy individuals. CEs are generally perceived by the users as effective, with related enthusiastic anecdotal reports; however, their efficacy in healthy individuals is uncertain and any reported improvement temporary. Conversely, since most CEs are stimulants, the related modulation of central noradrenaline, glutamate, and dopamine levels may lead to cardiovascular, neurological and psychopathological complications. Furthermore, use of CEs can be associated with paradoxical short- and long-term cognitive decline; decreased potential for plastic learning; and addictive behaviour. Finally, the non-medical use of any potent psychotropic raises serious ethical and legal issues, with nootropics having the potential to become a major public health concern. Further studies investigating CE-associated social, psychological, and biological outcomes are urgently needed to allow firm conclusions to be drawn on the appropriateness of CE use in healthy individuals.
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Affiliation(s)
- Fabrizio Schifano
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, UK.
| | - Valeria Catalani
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, UK
| | - Safia Sharif
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, UK
| | - Flavia Napoletano
- East London Foundation Trust (ELFT), Newham Early Intervention Service, London, UK
| | - John Martin Corkery
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, UK
| | - Davide Arillotta
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, UK
| | - Suzanne Fergus
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, UK
| | - Alessandro Vento
- Department of Mental Health, ASL Roma 2, Rome, Italy
- Addictions' Observatory (ODDPSS), Rome, Italy
- Department of Psychology, Guglielmo Marconi University, Rome, Italy
| | - Amira Guirguis
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, UK
- Swansea University Medical School, Institute of Life Sciences 2, Swansea University, Singleton Park, Swansea, UK
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Napoletano F, Schifano F, Corkery JM, Guirguis A, Arillotta D, Zangani C, Vento A. The Psychonauts' World of Cognitive Enhancers. Front Psychiatry 2020; 11:546796. [PMID: 33024436 PMCID: PMC7516264 DOI: 10.3389/fpsyt.2020.546796] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 08/17/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND There is growing availability of novel psychoactive substances (NPS), including cognitive enhancers (CEs) which can be used in the treatment of certain mental health disorders. While treating cognitive deficit symptoms in neuropsychiatric or neurodegenerative disorders using CEs might have significant benefits for patients, the increasing recreational use of these substances by healthy individuals raises many clinical, medico-legal, and ethical issues. Moreover, it has become very challenging for clinicians to keep up-to-date with CEs currently available as comprehensive official lists do not exist. METHODS Using a web crawler (NPSfinder®), the present study aimed at assessing psychonaut fora/platforms to better understand the online situation regarding CEs. We compared NPSfinder® entries with those from the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) and from the United Nations Office on Drugs and Crime (UNODC) NPS databases up to spring 2019. Any substance that was identified by NPSfinder® was considered a CE if it was either described as having nootropic abilities by psychonauts or if it was listed among the known CEs by Froestl and colleagues. RESULTS A total of 142 unique CEs were identified by NPSfinder®. They were divided into 10 categories, including plants/herbs/products (29%), prescribed drugs (17%), image and performance enhancing drugs (IPEDs) (15%), psychostimulants (15%), miscellaneous (8%), Phenethylamines (6%), GABAergic drugs (5%), cannabimimetic (4%), tryptamines derivatives (0.5%), and piperazine derivatives (0.5%). A total of 105 chemically different substances were uniquely identified by NPSfinder®. Only one CE was uniquely identified by the EMCDDA; no CE was uniquely identified by the UNODC. CONCLUSIONS These results show that NPSfinder® is helpful as part of an Early Warning System, which could update clinicians with the growing numbers and types of nootropics in the increasingly difficult-to-follow internet world. Improving clinicians' knowledge of NPS could promote more effective prevention and harm reduction measures in clinical settings.
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Affiliation(s)
- Flavia Napoletano
- Department of Mental Health, Homerton University Hospital, East London Foundation Trust, London, United Kingdom
- Psychopharmacology, Drug Misuse, and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - Fabrizio Schifano
- Psychopharmacology, Drug Misuse, and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - John Martin Corkery
- Psychopharmacology, Drug Misuse, and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - Amira Guirguis
- Psychopharmacology, Drug Misuse, and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
- Swansea University Medical School, Institute of Life Sciences 2, Swansea University, Swansea, United Kingdom
| | - Davide Arillotta
- Psychopharmacology, Drug Misuse, and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
- Psychiatry Unit, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Caroline Zangani
- Psychopharmacology, Drug Misuse, and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
- Department of Health Sciences, University of Milan, Milan, Italy
| | - Alessandro Vento
- Department of Mental Health, Addictions’ Observatory (ODDPSS), Rome, Italy
- Department of Mental Health, Guglielmo Marconi” University, Rome, Italy
- Department of Mental Health, ASL Roma 2, Rome, Italy
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Gvirts HZ, Mayseless N, Segev A, Lewis DY, Feffer K, Barnea Y, Bloch Y, Shamay-Tsoory SG. Novelty-seeking trait predicts the effect of methylphenidate on creativity. J Psychopharmacol 2017; 31:599-605. [PMID: 27624151 DOI: 10.1177/0269881116667703] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In recent years the use of psychostimulants for cognitive enhancement in healthy individuals with no psychiatric disorders has been on the rise. However, it is still unclear whether psychostimulants improve certain cognitive functions at the cost of others, and how these psychostimulants interact with individual personality differences. In the current study, we investigated whether the effect of one common stimulant, methylphenidate (MPH), on creativity is associated with novelty seeking. Thirty-six healthy adults, without attention-deficit hyperactivity disorder (ADHD) symptomology, were assigned randomly in a double-blind fashion to receive MPH or placebo. We found that the effect of MPH on creativity was dependent on novelty-seeking (NS) personality characteristics of the participants. MPH increased creativity in individuals with lower NS, while it reduced creativity levels in individuals with high NS. These findings highlight the role of the dopaminergic system in creativity, and indicate that among healthy individuals NS can be seen as a predictor of the effect of MPH on creativity.
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Affiliation(s)
- Hila Z Gvirts
- 1 Department of Psychology, University of Haifa, Haifa, Israel
| | - Naama Mayseless
- 1 Department of Psychology, University of Haifa, Haifa, Israel
| | - Aviv Segev
- 2 Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel.,3 The Emotion-Cognition Research Center, Shalvata Mental Health Care Center, Hod-Hasharon, affiliated with the Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - D Yael Lewis
- 2 Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel.,3 The Emotion-Cognition Research Center, Shalvata Mental Health Care Center, Hod-Hasharon, affiliated with the Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Kfir Feffer
- 2 Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel.,3 The Emotion-Cognition Research Center, Shalvata Mental Health Care Center, Hod-Hasharon, affiliated with the Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Yael Barnea
- 2 Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Yuval Bloch
- 2 Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel.,3 The Emotion-Cognition Research Center, Shalvata Mental Health Care Center, Hod-Hasharon, affiliated with the Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
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Kantak KM, Wettstein JG. Closing thoughts for cognitive enhancement. Handb Exp Pharmacol 2015; 228:451-9. [PMID: 25977093 DOI: 10.1007/978-3-319-16522-6_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The wide-ranging field of cognition enhancing research along with its ethics as it stands today is summarized. In the forefront are potentially novel drugs and non-pharmacological treatments for cognitive impairment across many different psychiatric and neurologic indications. Today's research will bring new drugs to patients tomorrow, and tomorrow's research will bring new molecular targets to clinical development that should be cognitive domain-specific. There is the likelihood that special populations may be better treated and that personalized medicine for cognitive impairment could become a reality. It is conceivable that with the current research effort, cognition enhancing drugs will become available to wide-ranging populations of people with neuropsychiatric illness and to those that are healthy. In some cultures, there is a push in society to be more intelligent or have more cognitive prowess. Thus, the ethical use of cognitive enhancing drugs should be an area of debate and communication. Neuroethics is a growing field and it intends to bring together key contributors such as physicians, disease experts, regulatory officials, and policy makers to discuss how such medicines can or should be made available. Together with this, one has to consider the possibility that no single medicine or technology will have a great impact on cognition and, therefore, combination therapy of drugs plus other approaches like exercise or transcranial direct-current stimulation may be the path forward. This is another area of scientific inquiry and debate, and the results should be fruitful and helpful to patients. The science of cognition is advancing at a rapid rate, and communication of its progress along with the development of rational and ethical policies for use of cognitive enhancers will be beneficial.
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Affiliation(s)
- Kathleen M Kantak
- Department of Psychological and Brain Sciences, Boston University, 64 Cummington Mall, Boston, MA, 02215, USA,
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Mohamed AD, Lewis CR. Modafinil increases the latency of response in the Hayling Sentence Completion Test in healthy volunteers: a randomised controlled trial. PLoS One 2014; 9:e110639. [PMID: 25391155 PMCID: PMC4229110 DOI: 10.1371/journal.pone.0110639] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 09/07/2014] [Indexed: 11/24/2022] Open
Abstract
Background Modafinil is a medication licensed for the treatment of narcolepsy. However, it has been reported that healthy individuals without wakefulness disorders are using modafinil off-label to enhance cognitive functioning. Although some studies have reported that modafinil improves cognitive task performance in healthy volunteers, numerous other studies have failed to detect cognitive enhancing effects of modafinil on several well-established neuropsychological tasks. Interestingly, several clinical and preclinical studies have found that improved cognitive task performance by modafinil is accompanied by slower response times. This observation raises the question as to whether this slowing of response time in healthy volunteers is a necessary and sufficient condition for cognitive enhancement with modafinil. The aim of the current experiment was to explore this question by investigating the effects of modafinil on the Hayling Sentence Completion Test (HSCT). Methodology Sixty-four healthy volunteers received either a single dose (200 mg) of modafinil (n = 32) or placebo (n = 32) in a randomized, double-blind, placebo-controlled, parallel group study in which the principal outcome measures were response latencies on the response initiation and response inhibition sections of the HSCT. Principal Findings Participants dosed with modafinil had significantly longer mean response latencies on the HSCT for both the response initiation and response inhibition compared to participants dosed with placebo. However, participants in both groups made a similar number of errors on each of these measures, indicating that modafinil did not enhance the accuracy of performance of the task relative to placebo. Conclusions This study demonstrated that administration of single 200 mg doses of modafinil to healthy individuals increased the latency of responses in the performance of the HSCT, a task that is highly sensitive to prefrontal executive function, without enhancing accuracy of performance. This finding may provide important clues to defining the limitations of modafinil as a putative cognitive enhancer. Trial Registration ClinicalTrials.gov NCT02051153
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Affiliation(s)
- Ahmed Dahir Mohamed
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom
- The School of Psychology, Cognitive and Sensory Systems Group, Faculty of Science, University of Nottingham Malaysia Campus, Selangor, Malaysia
- Clare Hall College, Cambridge, United Kingdom
- * E-mail:
| | - Chris Roberts Lewis
- Department of Psychology, Towson University, 8000 York Road, Towson, Maryland, 21252-0001, United States of America
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Mohamed AD. The Effects of Modafinil on Convergent and Divergent Thinking of Creativity: A Randomized Controlled Trial. JOURNAL OF CREATIVE BEHAVIOR 2014. [DOI: 10.1002/jocb.73] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Racine E, Martin Rubio T, Chandler J, Forlini C, Lucke J. The value and pitfalls of speculation about science and technology in bioethics: the case of cognitive enhancement. MEDICINE, HEALTH CARE, AND PHILOSOPHY 2014; 17:325-37. [PMID: 24402841 DOI: 10.1007/s11019-013-9539-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In the debate on the ethics of the non-medical use of pharmaceuticals for cognitive performance enhancement in healthy individuals there is a clear division between those who view "cognitive enhancement" as ethically unproblematic and those who see such practices as fraught with ethical problems. Yet another, more subtle issue, relates to the relevance and quality of the contribution of scholarly bioethics to this debate. More specifically, how have various forms of speculation, anticipatory ethics, and methods to predict scientific trends and societal responses augmented or diminished this contribution? In this paper, we use the discussion of the ethics of cognitive enhancement to explore the positive and negative contribution of speculation in bioethics scholarship. First, we review and discuss how speculation has relied on different sets of assumptions regarding the non-medical use of stimulants, namely: (1) terminology and framing; (2) scientific aspects such as efficacy and safety; (3) estimates of prevalence and consequent normalization; and (4) the need for normative reflection and regulatory guidelines. Second, three methodological guideposts are proposed to alleviate some of the pitfalls of speculation: (1) acknowledge assumptions more explicitly and identify the value attributed to assumptions; (2) validate assumptions with interdisciplinary literature; and (3) adopt a broad perspective to promote more comprehensive reflection. We conclude that, through the examination of the controversy about cognitive enhancement, we can employ these methodological guideposts to enhance the value of contributions from bioethics and minimize potential epistemic and practical pitfalls in this case and perhaps in other areas of bioethical debate.
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Affiliation(s)
- Eric Racine
- Neuroethics Research Unit, Institut de recherches cliniques de Montréal (IRCM), 110 Avenue des Pins Ouest, Montreal, QC, H2W lR7, Canada,
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Mohamed AD. Neuroethical issues in pharmacological cognitive enhancement. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2014; 5:533-549. [PMID: 26308743 DOI: 10.1002/wcs.1306] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 05/31/2014] [Accepted: 06/22/2014] [Indexed: 12/11/2022]
Abstract
UNLABELLED Neuroethics is an emerging field that in general deals with the ethics of neuroscience and the neuroscience of ethics. In particular, it is concerned with the ethical issues in the translation of neuroscience to clinical practice and in the public domain. Numerous ethical issues arise when healthy individuals use pharmacological substances known as pharmacological cognitive enhancers (PCEs) for non-medical purposes in order to boost higher-order cognitive processes such as memory, attention, and executive functions. However, information regarding their actual use, benefits, and harms to healthy individuals is currently lacking. Neuroethical issues that arise from their use include the unknown side effects that are associated with these drugs, concerns about the modification of authenticity and personhood, and as a result of inequality of access to these drugs, the lack of distributive justice and competitive fairness that they may cause in society. Healthy individuals might be coerced by social institutions that force them to take these drugs to function better. These drugs might enable or hinder healthy individuals to gain better moral and self-understanding and autonomy. However, how these drugs might achieve this still remains speculative and unknown. Hence, before concrete policy decisions are made, the cognitive effects of these drugs should be determined. The initiation of accurate surveys to determine the actual usage of these drugs by healthy individuals from different sections of the society is proposed. In addition, robust empirical research need to be conducted to delineate not only whether or not these drugs modify complex higher-order cognitive processes but also how they might alter important human virtues such as empathy, moral reasoning, creativity, and motivation in healthy individuals. WIREs Cogn Sci 2014, 5:533-549. doi: 10.1002/wcs.1306 For further resources related to this article, please visit the WIREs website. CONFLICT OF INTEREST The author has declared no conflicts of interest for this article.
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Affiliation(s)
- Ahmed Dahir Mohamed
- The School of Psychology, Cognitive and Sensory Systems Group, Faculty of Science, University of Nottingham, Royal Selangor, Malaysia.,Department of Psychiatry, Cambridge School of Clinical Medicine, University of Cambridge, Cambridge, UK.,Clare Hall College, Cambridge, UK
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Silveira RDR, Lejderman B, Ferreira PEMS, Rocha GMPD. Patterns of non-medical use of methylphenidate among 5th and 6th year students in a medical school in southern Brazil. TRENDS IN PSYCHIATRY AND PSYCHOTHERAPY 2014; 36:101-6. [DOI: 10.1590/2237-6089-2013-0065] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Objectives: To evaluate the prevalence of methylphenidate (MPH) use among 5th and 6th year medical students, to discriminate MPH use with and without medical indication, and to correlate MPH use with alcohol intake. Methods: This is a cross-sectional study in which medical students were invited to answer a questionnaire to evaluate academic and socioeconomic status, MPH use patterns, and attitudes towards neuroenhancing drugs. The Alcohol Use Disorders Identification Test (AUDIT) was used to assess alcohol intake; a score ≥ 8 suggests potentially hazardous alcohol use. Results: Fifty-two participants (34.2%) had already used MPH, of which 35 (23.02%) had used it without medical indication. The number of 6th year students who had used MPH was more than twice higher than that of their 5th year counterparts (32.89 vs. 13.15%, respectively; p = 0.004). Also, 43.6% (p = 0.031) of the users of MPH had an AUDIT score ≥ 8; 33.3% (p = 0.029) of non-medical users of MPH had an AUDIT score ≥ 8. Conclusions: In this study, the use of MPH without medical indication was prevalent. Our findings also confirmed the association between non-medical use of MPH and potentially hazardous alcohol use.
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Neuroethics: A Moral Approach towards Neuroscience Research. ARCHIVES OF NEUROSCIENCE 2014. [DOI: 10.5812/archneurosci.19224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Mohamed AD. Reducing Creativity With Psychostimulants May Debilitate Mental Health and Well-Being. JOURNAL OF CREATIVITY IN MENTAL HEALTH 2014. [DOI: 10.1080/15401383.2013.875865] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Enhance, delete, incept: manipulating hippocampus-dependent memories. Brain Res Bull 2014; 105:2-7. [PMID: 24397964 PMCID: PMC4058530 DOI: 10.1016/j.brainresbull.2013.12.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 12/20/2013] [Accepted: 12/24/2013] [Indexed: 11/28/2022]
Abstract
Newly developed methods allow manipulation of hippocampus-dependent memories. Cued reactivation during sleep and transcranial stimulation can enhance memories. Pharmacological agents can delete memories. Optogenetics and DREADDs can be used to incept memories. Electrophysiology and fMRI have been used to investigate the underlying mechanisms.
Here we provide a brief overview of recent research on memory manipulation. We focus primarily on memories for which the hippocampus is thought to be required due to its central importance in the study of memory. The repertoire of methods employed is expanding and includes optogenetics, transcranial stimulation, deep brain stimulation, cued reactivation during sleep and the use of pharmacological agents. In addition, the possible mechanisms underlying these memory changes have been investigated using techniques such as single unit recording and functional magnetic resonance imaging (fMRI). This article is part of a Special Issue entitled ‘Memory enhancement’.
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Aggarwal NK, Ford E. The neuroethics and neurolaw of brain injury. BEHAVIORAL SCIENCES & THE LAW 2013; 31:789-802. [PMID: 24123245 DOI: 10.1002/bsl.2086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 07/18/2013] [Accepted: 07/30/2013] [Indexed: 06/02/2023]
Abstract
Neuroethics and neurolaw are fields of study that involve the interface of neuroscience with clinical and legal decision-making. The past two decades have seen increasing attention being paid to both fields, in large part because of the advances in neuroimaging techniques and improved ability to visualize and measure brain structure and function. Traumatic brain injury (TBI), along with its acute and chronic sequelae, has emerged as a focus of neuroethical issues, such as informed consent for treatment and research, diagnostic and prognostic uncertainties, and the subjectivity of interpretation of data. The law has also more frequently considered TBI in criminal settings for exculpation, mitigation and sentencing purposes and in tort and administrative law for personal injury, disability and worker's compensation cases. This article provides an overview of these topics with an emphasis on the current challenges that the neuroscience of TBI faces in the medicolegal arena.
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Affiliation(s)
- Neil Krishan Aggarwal
- New York State Psychiatric Institute, 1051 Riverside Drive, Unit 11, New York, NY, 10032, U.S.A.; Department of Psychiatry, Columbia University, 1051 Riverside Drive, Unit 11, New York, NY, 10032, U.S.A
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Navigating the enhancement landscape. Ethical issues in research on cognitive enhancers for healthy individuals. EMBO Rep 2013; 14:123-8. [PMID: 23318628 DOI: 10.1038/embor.2012.225] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Müller U, Rowe J, Rittman T, Lewis C, Robbins T, Sahakian B. Effects of modafinil on non-verbal cognition, task enjoyment and creative thinking in healthy volunteers. Neuropharmacology 2012; 64:490-5. [PMID: 22820554 PMCID: PMC3485563 DOI: 10.1016/j.neuropharm.2012.07.009] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 07/02/2012] [Accepted: 07/04/2012] [Indexed: 12/22/2022]
Abstract
Background Modafinil, a putative cognitive enhancing drug, has previously been shown to improve performance of healthy volunteers as well as patients with attention deficit disorder and schizophrenia, mainly in tests of executive functions. The aim of this study was to investigate the effects of modafinil on non-verbal cognitive functions in healthy volunteers, with a particular focus on variations of cognitive load, measures of motivational factors and the effects on creative problem-solving. Methods A double-blind placebo-controlled parallel design study evaluated the effect of 200 mg of modafinil (N = 32) or placebo (N = 32) in non-sleep deprived healthy volunteers. Non-verbal tests of divergent and convergent thinking were used to measure creativity. A new measure of task motivation was used, together with more levels of difficulty on neuropsychological tests from the CANTAB battery. Results Improvements under modafinil were seen on spatial working memory, planning and decision making at the most difficult levels, as well as visual pattern recognition memory following delay. Subjective ratings of enjoyment of task performance were significantly greater under modafinil compared with placebo, but mood ratings overall were not affected. The effects of modafinil on creativity were inconsistent and did not reach statistical significance. Conclusions Modafinil reliably enhanced task enjoyment and performance on several cognitive tests of planning and working memory, but did not improve paired associates learning. The findings confirm that modafinil can enhance aspects of highly demanding cognitive performance in non-sleep deprived individuals. This article is part of a Special Issue entitled ‘Cognitive Enhancers’.
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Affiliation(s)
- U. Müller
- Department of Psychiatry, University of Cambridge, School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
- MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute (BCNI), University of Cambridge, Cambridge, UK
| | - J.B. Rowe
- MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute (BCNI), University of Cambridge, Cambridge, UK
- Department of Clinical Neuroscience, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | - T. Rittman
- Department of Clinical Neuroscience, University of Cambridge School of Clinical Medicine, Cambridge, UK
| | - C. Lewis
- Department of Psychiatry, University of Cambridge, School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
| | - T.W. Robbins
- MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute (BCNI), University of Cambridge, Cambridge, UK
- Department of Experimental Psychology, Downing Street, University of Cambridge, Cambridge, UK
| | - B.J. Sahakian
- Department of Psychiatry, University of Cambridge, School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK
- MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute (BCNI), University of Cambridge, Cambridge, UK
- Oxford Uehiro Centre for Practical Ethics, University of Oxford, Oxford, UK
- Corresponding author. University of Cambridge, Department of Psychiatry (Box 189), Addenbrooke's Hospital, Hill's Road, Cambridge CB2 2QQ, UK. Tel.: +44 (0)1223 768506; fax: +44 (0)1223 336968.
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Atomoxetine modulates spontaneous and sensory-evoked discharge of locus coeruleus noradrenergic neurons. Neuropharmacology 2012; 64:53-64. [PMID: 22820275 DOI: 10.1016/j.neuropharm.2012.07.020] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 07/09/2012] [Accepted: 07/11/2012] [Indexed: 11/24/2022]
Abstract
Atomoxetine (ATM) is a potent norepinephrine (NE) uptake inhibitor and increases both NE and dopamine synaptic levels in prefrontal cortex, where it is thought to exert its beneficial effects on attention and impulsivity. At the behavioral level, ATM has been shown to cause improvements on the measures of executive functions, such as response inhibition, working memory and attentional set shifting across different species. However, the exact mechanism of action for ATM's effects on cognition is still not clear. One possible target for the cognitive enhancing effects of ATM is the noradrenergic locus coeruleus (LC), the only source of NE to key forebrain areas such as cerebral cortex and hippocampus. Although it is known that ATM increases NE availability overall by blocking reuptake of NE, the effects of this agent on impulse activity of LC neurons have not been reported. Here, the effect of ATM (0.1-1 mg/kg, ip) on NE-LC neurons was investigated by recording extracellular activity of LC neurons in isoflurane-anesthetized rats. ATM caused a significant decrease of the tonic activity of LC single-units, although leaving intact the sensory-evoked excitatory component of LC phasic response. Moreover, the magnitude of the inhibitory component of LC response to paw stimulation was increased after 1 mg/kg of ATM and its duration was prolonged at 0.3 mg/kg. Together, these effects of ATM produced an increase in the phasic-to-tonic ratio of LC phasic response to sensory stimulation. ATM also modulated the average sensory-evoked local field potential (LFP) and spike-field coherence in LC depending on the dose tested. The lower dose (0.1 mg/kg) significantly decreased early positive and negative components of the sensory-evoked LFP response. Higher doses (0.3-1 mg/kg) initially increased and then decreased the amplitude of components of the evoked fields, whereas the spike-field coherence was enhanced by 1 mg/kg ATM across frequency bands. Finally, coherence between LC fields and EEG signals was generally increased by 1 mg/kg ATM, whereas 0.1 and 0.3 mg/kg respectively decreased and increased coherence values in specific frequency bands. Taken together these results suggest that ATM effects on LC neuronal activity are dose-dependent, with different doses affecting different aspects of LC firing. This modulation of activity of LC-NE neurons may play a role in the cognitive effects of ATM. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
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Partridge BJ, Bell SK, Lucke JC, Yeates S, Hall WD. Smart drugs "as common as coffee": media hype about neuroenhancement. PLoS One 2011; 6:e28416. [PMID: 22140584 PMCID: PMC3227668 DOI: 10.1371/journal.pone.0028416] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 11/07/2011] [Indexed: 12/03/2022] Open
Abstract
Background The use of prescription drugs to improve cognitive functioning in normal persons –“neuroenhancement” – has gained recent attention from bioethicists and neuroscientists. Enthusiasts claim that the practice is widespread and increasing, and has many potential benefits; however recent evidence provides weak support for these claims. In this study we explored how the newsprint media portrays neuroenhancement. Aims We conducted an empirical study of media reporting of neuroenhancement to explore: media portrayals of the prevalence of neuroenhancement; the types of evidence used by the media to support claims about its prevalence; and, the possible benefits and risks of neuroenhancement mentioned in these media articles. Methods Using the Factiva database, we found 142 newspaper articles about the non-medical use prescription drugs for neuroenhancement for the period 2008-2010. We conducted a thematic content analysis of how articles portrayed the prevalence of neuroenhancement; what type of evidence they used in support; and, the potential benefits and risks/side-effects of neuroenhancement that were mentioned. Results 87% of media articles mentioned the prevalence of neuroenhancement, and 94% portrayed it as common, increasing or both. 66% referred to the academic literature to support these claims and 44% either named an author or a journal. 95% of articles mentioned at least one possible benefit of using prescription drugs for neuroenhancement, but only 58% mentioned any risks/side effects. 15% questioned the evidence for efficacy of prescription drugs to produce benefits to users. Conclusions News media articles mentioned the possible benefits of using drugs for neuroenhancement more than the potential risks/side effects, and the main source for media claims that neuroenhancement is common and increasingly widespread has been reports from the academic literature that provide weak support for this claim. We urge journalists and researchers to be cautious in their portrayal of the non-medical use of drugs for neuroenhancement.
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Affiliation(s)
- Bradley J Partridge
- UQ Centre for Clinical Research, The University of Queensland, Herston, Queensland, Australia.
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