Moral Enhancement Using Non-invasive Brain Stimulation

Forensic neurology: a distinct subspecialty at the intersection of neurology, neuroscience and law

Neurological evidence is increasingly used in criminal cases to argue that a defendant is less responsible for their behaviour, is not competent to stand trial or should receive a reduced punishment for the crime. Unfortunately, neurologists are rarely involved in such cases despite having the expertise to help to inform these decisions in court. In this Perspective, we advocate for the development of 'forensic neurology', a subspecialty of neurology focused on using neurological clinical and scientific expertise to address legal questions for the criminal justice system. We review literature suggesting that the incidence of criminal behaviour is higher in people with certain neurological disorders than the general public and that undiagnosed neurological abnormalities are common in people who commit crimes. We discuss the need for forensic neurologists in criminal cases to provide an opinion on what neurological diagnoses are present, the resulting symptoms and ultimately whether the symptoms affect legal determinations such as criminal responsibility or competency.

To bridge or not to bridge: Moral Judgement in Cocaine Use Disorders, a case-control study on human morality

BACKGROUND

In the "Dual-Process theory", morality is characterized by the interaction between an automatic-emotional process, mediated by the Anterior Cingulate Cortex (ACC) and linked to personal-deontological decisions, and a rational-conscious one, mediated by the Dorso-Lateral Prefrontal Cortex (DLPFC) and linked to impersonal-utilitarian decisions. These areas are altered by chronic use of cocaine, with a possible impact on moral decision-making.

OBJECTIVE

To evaluate the difference between a group of Cocaine Use Disorder (CUD) patients and a control group in moral decision-making.

METHODS

Subjects with CUD were compared to an equal-sized healthy group regarding their moral decision-making. Trolley and Footbridge Moral Dilemmas were administered to each group. The quality of the answer (yes or no) and the time needed to answer were recorded.

RESULTS

The recruited group includes 72 subjects, 36 with CUD and 36 healthy subjects (average age of 39.51 ± 9.89). In the Trolley dilemma, almost all the subjects (97.3%) answered "yes", while in the Footbridge dilemma CUD subjects answered "yes" more often (52.7%) than the healthy group (19.4%).

CONCLUSION

For strong emotional dilemmas (Footbridge), cocaine users answered "yes" with a higher frequency compared to healthy subjects, highlighting a wider utilitarian tendency in decision-making and a poor emotional participation.

Network localization of antisocial behavior in neurological patients: Evidence and implications

Antisocial behavior may develop in otherwise normal persons as a result of neurological diseases, including patients with focal brain lesions, frontotemporal dementia, and Parkinson Disease patients taking dopamine agonist medications. Evidence from these neurological patients demonstrates that antisocial behaviors relate to dysfunction in several different brain regions that form a specific brain network, rather than any single location alone. This network associated with acquired antisocial behavior is involved in social decision-making (measured using moral decision-making tasks) and value-based decision-making (measured using neuroeconomic and reward-based tasks). Collectively, this work supports the hypothesis that antisocial behavior across different neurological diseases results from dysfunction within a common network of brain regions associated with social valuation and decision-making, providing insight into the neural mechanisms leading to acquired antisocial behavior. These findings have important implications, but also important limitations, for understanding criminal behavior in patients with psychopathy, for rehabilitation in criminals, for ethical discussions regarding moral and legal responsibility, and for forensic neurological evaluations in persons accused of crimes.

How Imagination and Memory Shape the Moral Mind

Interdisciplinary research has proposed a multifaceted view of human cognition and morality, establishing that inputs from multiple cognitive and affective processes guide moral decisions. However, extant work on moral cognition has largely overlooked the contributions of episodic representation. The ability to remember or imagine a specific moment in time plays a broadly influential role in cognition and behavior. Yet, existing research has only begun exploring the influence of episodic representation on moral cognition. Here, we evaluate the theoretical connections between episodic representation and moral cognition, review emerging empirical work revealing how episodic representation affects moral decision-making, and conclude by highlighting gaps in the literature and open questions. We argue that a comprehensive model of moral cognition will require including the episodic memory system, further delineating its direct influence on moral thought, and better understanding its interactions with other mental processes to fundamentally shape our sense of right and wrong.

Can we rewire criminal mind via non-invasive brain stimulation of prefrontal cortex? Insights from clinical, forensic and social cognition studies

Non-compliance with social and legal norms and regulations represents a high burden for society. Social cognition deficits are frequently called into question to explain criminal violence and rule violations in individuals diagnosed with antisocial personality disorder (APD), borderline personality disorder (BPD), and psychopathy. In this article, we proposed to consider the potential benefits of non-invasive brain stimulation (NIBS) to rehabilitate forensic population. We focused on the effects of NIBS of the prefrontal cortex, which is central in social cognition, in modulating aggression and impulsivity in clinical disorders, as well as in forensic population. We also addressed the effect of NIBS on empathy, and theory of mind in non-clinical and/or prison population. The reviewed data provide promising evidence on the beneficial effect of NIBS on aggression/impulsivity dyscontrol and social cognitive functions, suggesting its relevance in promoting reintegration of criminals into society.

Causal evidence of the roles of the prefrontal and occipital cortices in modulating the impact of color on moral judgement

Moral judgment is known to be affected by factors such as color. Previous research has shown that the colors black and white are particularly important, however, the neural mechanisms underlying this effect remain unclear. This study aimed to investigate the causal relationship between specific brain regions (left dorsolateral prefrontal cortex, left DLPFC and occipital cortex, OC) and their impact of black and white moral judgement by using transcranial direct current stimulation (tDCS). The results of Experiment 1 (N = 54) and Experiment 2 (N = 66) showed that anodal tDCS over the left DLPFC inhibited the impact of black and white on moral judgment while cathodal tDCS over the left DLPFC enhanced the effect. Conversely, anodal tDCS over the OC enhanced the impact of white on moral judgment, while cathodal tDCS over the OC inhibited it. Together these results suggest that moral judgment relies not only on the cognitive control network, but also brain regions important for sensory perception. The current findings provide enhanced insight into how colors can impact moral judgments.

Cultivating conscience: Moral neurohabilitation of adolescents and young adults with conduct and/or antisocial personality disorders

Individuals diagnosed with conduct disorder (CD) in childhood and adolescence are at risk for increasingly maladaptive and dangerous behaviors, which unchecked, can lead to antisocial personality disorder (ASPD) in adulthood. Children with CD, especially those with the callous unemotional subgroup qualifier ("limited prosocial emotions"/DSM-5), present with a more severe pattern of delinquency, aggression, and antisocial behavior, all markings of prodrome ASPD. Given this recognized diagnostic trajectory, with a pathological course playing out tragically at the individual, familial, and societal level, and lack of effective remediation via current standards of care, we posit an alternate treatment approach; case-specific compulsory moral habilitation aimed at rectifying the undeveloped affective domain of adolescents and young adults suffering from these disorders. We begin with a brief historical overview of response to mental illness, review CD and ASPD diagnostic criteria and treatment limitations, and posit a unique neurohabilitative approach that focuses on the absent affective moral development of these populations. Next, we invoke a public health safety argument to justify case-specific compulsory moral habilitation, discuss neurotechnologies to be considered in treatment, and conclude with ethical considerations and suggestions for further research.

Transcranial electric stimulation as a neural interface to gain insight on human brain functions: current knowledge and future perspective

The use of brain-stimulation approaches in social and affective science has greatly increased over the last two decades. The interest in social factors has grown along with technological advances in brain research. Transcranial electric stimulation (tES) is a research tool that allows scientists to establish contributory causality between brain functioning and social behaviour, therefore deepening our understanding of the social mind. Preliminary evidence is also starting to demonstrate that tES, either alone or in combination with pharmacological or behavioural interventions, can alleviate the symptomatology of individuals with affective or social cognition disorders. This review offers an overview of the application of tES in the field of social and affective neuroscience. We discuss issues and challenges related to this application and suggest avenue for future basic and translational research.

Modulating activity in the dorsolateral prefrontal cortex alter corruption behavior: A transcranial direct current stimulation study

Corruption behavior has gained worldwide concern for its great harmfulness to public society. In order to reduce corruption, researchers have carried out numerous studies on corrupt prevention. Researchers found that except for external supervision, the internal factor such as moral judgment also have an impact on corruption behavior. Previous brain imaging and stimulation studies suggested that dorsolateral prefrontal cortex (DLPFC) is critical brain area which integrates emotional and cognitive process of moral judgments. Therefore, in the current study, we applied tDCS (transcranial direct current stimulation) over DLPFC to investigated the modulation effect of cortical excitability on corruption behavior. According to the characteristics of corruption, we designed an incomplete information invest game task based on trust game, then adopted a between-subject design to compare participants' corruption rate and reaction time (RT) among right anodal/left cathodal, left anodal/right cathodal and sham tDCS. The results showed that, in contrast to sham stimulation, left anodal/right cathodal tDCS reduced corruption rate both in high and low entrusted amount while right anodal/left cathodal tDCS only prolonged subjects' reaction time (RT) of dishonest response only in high entrusted amount. A possible explanation for the results of current study is that the left DLPFC is associated with the emotional process, which influenced the moral intuition aspect of moral judgment and reflected in the change of immoral behavior rate. While the right DLPFC is associated with cognitive control, which influenced the moral reasoning aspect of moral judgment and reflected in the change of reaction time. This explanation is also consistent with the Emotion-Evoked Collective Corruption Model and dual process theory of brain function.

Transcranial direct current stimulation (tDCS) as an intervention to improve empathic abilities and reduce violent behavior in forensic offenders: study protocol for a randomized controlled trial

BACKGROUND

Recent studies show that changes in one of the brain areas related to empathic abilities (i.e. the ventromedial prefrontal cortex (vmPFC)) plays an important role in violent behavior in abusers of alcohol and cocaine. According to the models of James Blair, empathy is a potential inhibitor of violent behavior. Individuals with less empathic abilities may be less susceptible and motivated to inhibit violent behavior, which causes a higher risk of violence. Recent neuroscientific research shows that modulating (stimulation or inhibition) certain brain areas could be a promising new intervention for substance abuse and to reduce violent behavior, such as the neurostimulation technique transcranial direct current stimulation (tDCS). This study aims to investigate tDCS as an intervention to increase empathic abilities and reduce violent behavior in forensic substance use offenders.

METHODS/DESIGN

A total sample of 50 male forensic substance abuse patients (25 active and 25 sham stimulation) will be tested in a double-blind placebo-controlled study, from which half of the patients will receive an active stimulation plus treatment as usual (TAU) and the other half will receive sham stimulation (placebo) plus TAU. The patients in the active condition will receive multichannel tDCS targeting the bilateral vmPFC two times a day for 20 min for five consecutive days. Before and after the stimulation period, the patients will complete self-report measurements, perform the Point Subtraction Aggression Paradigm (PSAP) and a passive viewing empathy task. Resting state electroencephalography (rsEEG) will be performed before and after the treatment period. A follow up will be conducted after 6 months. The primary outcome is to investigate multichannel tDCS as a new intervention to increase empathic abilities and reduce violent behavior in offenders with substance abuse problems. In addition, we will determine whether electrophysiological responses in the brain are affected by the tDCS intervention. Finally, the effects of tDCS on reducing craving will be investigated.

DISCUSSION

This study is one of the first studies using multichannel tDCS targeting the vmPFC in a forensic sample. This study will explore the opportunities to introduce a new intervention to improve empathic abilities and reduce violence in forensic substance use offenders. Specifically, this study may give insight into how to implement the tDCS intervention in the setting of daily clinical practice in this complex, multiple-problem target group and with that contribute to reduction of recidivism.

TRIAL REGISTRATION

Dutch Trial Register, NTR7701. Registered on 12 January 2019. Prospectively registered before the recruitment phase. https://www.trialregister.nl/trial/7459. Recruitment started on the 1st of February 2019 and will be finished approximately in the winter of 2019. Protocol version 1. 22 May 2019.

Gender and Hemispheric Asymmetries in Acquired Sociopathy

The emergence of enduring antisocial personality changes in previously normal individuals, or "acquired sociopathy," has consistently been reported in patients with bilateral injuries of the ventromedial prefrontal cortex. Over the past three decades, cases of acquired sociopathy with (a) bilateral or (b) unilateral sparing of the ventromedial prefrontal cortex have been reported. These cases indicate that at least in a few individuals (a') neural structures beyond the ventromedial prefrontal cortex are also critical for normal social behavior, and (b') the neural underpinnings of social cognition may be lateralized to one cerebral hemisphere. Moreover, researchers have presented evidence that lesion laterality and gender may interact in the production of acquired sociopathy. In the present review, we carried out a comprehensive literature survey seeking possible interactions between gender and hemispheric asymmetry in acquired sociopathy. We found 85 cases of acquired sociopathy due to bilateral (N = 48) and unilateral (N = 37) hemispheric injuries. A significant association between acquired sociopathy and right hemisphere damage was found in men, whereas lesions were bilateral in most women with acquired sociopathy. The present survey shows that: (i) the number of well-documented single-cases of acquired sociopathy is surprisingly small given the length of the historical record; (ii) acquired sociopathy was significantly more frequent in men after an injury of the right or of both cerebral hemispheres; and (iii) in most women who developed acquired sociopathy the injuries affected both cerebral hemispheres. These findings may be especially valuable to neuroscientists and to functional neurosurgeons in particular for the planning of tumor resections as well as for the choice of the best targets for therapeutic neuromodulation.

Low intensity transcranial electric stimulation: Safety, ethical, legal regulatory and application guidelines

Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears to be safe. No serious adverse events (SAEs) have been reported so far in over 18,000 sessions administered to healthy subjects, neurological and psychiatric patients, as summarized here. Moderate adverse events (AEs), as defined by the necessity to intervene, are rare, and include skin burns with tDCS due to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue following stimulation as well as prickling and burning sensations occurring during tDCS at peak-to-baseline intensities of 1-2mA and during tACS at higher peak-to-peak intensities above 2mA. The prevalence of published AEs is different in studies specifically assessing AEs vs. those not assessing them, being higher in the former. AEs are frequently reported by individuals receiving placebo stimulation. The profile of AEs in terms of frequency, magnitude and type is comparable in healthy and clinical populations, and this is also the case for more vulnerable populations, such as children, elderly persons, or pregnant women. Combined interventions (e.g., co-application of drugs, electrophysiological measurements, neuroimaging) were not associated with further safety issues. Safety is established for low-intensity 'conventional' TES defined as <4mA, up to 60min duration per day. Animal studies and modeling evidence indicate that brain injury could occur at predicted current densities in the brain of 6.3-13A/m2 that are over an order of magnitude above those produced by tDCS in humans. Using AC stimulation fewer AEs were reported compared to DC. In specific paradigms with amplitudes of up to 10mA, frequencies in the kHz range appear to be safe. In this paper we provide structured interviews and recommend their use in future controlled studies, in particular when trying to extend the parameters applied. We also discuss recent regulatory issues, reporting practices and ethical issues. These recommendations achieved consensus in a meeting, which took place in Göttingen, Germany, on September 6-7, 2016 and were refined thereafter by email correspondence.