Genetically-Driven Enhancement of Dopaminergic Transmission Affects Moral Acceptability in Females but Not in Males: A Pilot Study

Moral behavior has been a key topic of debate for philosophy and psychology for a long time. In recent years, thanks to the development of novel methodologies in cognitive sciences, the question of how we make moral choices has expanded to the study of neurobiological correlates that subtend the mental processes involved in moral behavior. For instance, in vivo brain imaging studies have shown that distinct patterns of brain neural activity, associated with emotional response and cognitive processes, are involved in moral judgment. Moreover, while it is well-known that responses to the same moral dilemmas differ across individuals, to what extent this variability may be rooted in genetics still remains to be understood. As dopamine is a key modulator of neural processes underlying executive functions, we questioned whether genetic polymorphisms associated with decision-making and dopaminergic neurotransmission modulation would contribute to the observed variability in moral judgment. To this aim, we genotyped five genetic variants of the dopaminergic pathway [rs1800955 in the dopamine receptor D4 (DRD4) gene, DRD4 48 bp variable number of tandem repeat (VNTR), solute carrier family 6 member 3 (SLC6A3) 40 bp VNTR, rs4680 in the catechol-O-methyl transferase (COMT) gene, and rs1800497 in the ankyrin repeat and kinase domain containing 1 (ANKK1) gene] in 200 subjects, who were requested to answer 56 moral dilemmas. As these variants are all located in genes belonging to the dopaminergic pathway, they were combined in multilocus genetic profiles for the association analysis. While no individual variant showed any significant effects on moral dilemma responses, the multilocus genetic profile analysis revealed a significant gender-specific influence on human moral acceptability. Specifically, those genotype combinations that improve dopaminergic signaling selectively increased moral acceptability in females, by making their responses to moral dilemmas more similar to those provided by males. As females usually give more emotionally-based answers and engage the “emotional brain” more than males, our results, though preliminary and therefore in need of replication in independent samples, suggest that this increase in dopamine availability enhances the cognitive and reduces the emotional components of moral decision-making in females, thus favoring a more rationally-driven decision process

Attitudes Towards End-of-Life Decisions and the Subjective Concepts of Consciousness: An Empirical Analysis

Background: People have fought for their civil rights, primarily the right to live in dignity. At present, the development of technology in medicine and healthcare led to an apparent paradox: many people are fighting for the right to die. This study was aimed at testing whether different moral principles are associated with different attitudes towards end-of-life decisions for patients with a severe brain damage. Methodology: We focused on the ethical decisions about withdrawing life-sustaining treatments in patients with severe brain damage. 202 undergraduate students at the University of Padova were given one description drawn from four profiles describing different pathological states: the permanent vegetative state, the minimally conscious state, the locked-in syndrome, and the terminal illness. Participants were asked to evaluate how dead or how alive the patient was, and how appropriate it was to satisfy the patient's desire. Principal Findings: We found that the moral principles in which people believe affect not only people's judgments concerning the appropriateness of the withdrawal of life support, but also the perception of the death status of patients with severe brain injury. In particular, we found that the supporters of the Free Choice (FC) principle perceived the death status of the patients with different pathologies differently: the more people believe in the FC, the more they perceived patients as dead in pathologies where conscious awareness is severely impaired. By contrast, participants who agree with the Sanctity of Life (SL) principle did not show differences across pathologies. Conclusions: These results may shed light on the complex aspects of moral consensus for supporting or rejecting end-of-life decisions

A New Set of Moral Dilemmas: Norms for Moral Acceptability, Decision Times, and Emotional Salience

At the present time, the growing interest in the topic of moral judgment highlights the widespread need for a standardized set of experimental stimuli. We provide normative data for a sample of 120 undergraduate students using a new set of 60 moral dilemmas that might be employed in future studies according to specific research needs. Thirty dilemmas were structured to be similar to the Footbridge dilemma (“instrumental” dilemmas, in which the death of one person is ameans to save more people), and thirty dilemmaswere designed to be similar to the Trolley dilemma (“incidental” dilemmas, in which the death of one person is a foreseen but unintended consequence of the action aimed at saving more people). Besides type of dilemma, risk-involvement was also manipulated: the main character’s life was at risk in half of the instrumental dilemmas and in half of the incidental dilemmas. We provide normative values for the following variables: (i) rates of participants’ responses (yes/no) to the proposed resolution; (ii) decision times; (iii) ratings of moral acceptability; and (iv) ratings of emotional valence (pleasantness/unpleasantness) and arousal (activation/calm) experienced during decision making. For most of the dependent variables investigated, we observed significant main effects of type of dilemma and risk-involvement in both subject and item analyses

Conditionals and conditional thinking

In this paper, we claim that the problem of conditionals should be dealt with by carefully distinguishing between thinking conditional propositions and conditional thinking, i.e. thinking on the basis of some supposition. This distinction deserves further investigation, if we are to make sense of some old and new experimental data concerning the understanding and the assertion of conditional sentences. Here we will argue that some of these data seem to refute the mental models theory of conditional reasoning, setting the ground for a different approach to the cognitive study of conditionals

Asserzioni condizionali e di condizionali

Gli enunciati condizionali, che hanno la forma «se..., allora...», sono un dibattuto oggetto di studio della logica, della filosofia della logica e della psicologia del pensiero. La ricerca in queste tre aree si è sviluppata secondo linee diverse che raramente si sono intersecate. In particolare sono state scarse le connessioni tra la ricerca svolta in ambito logico o logico-filosofico e la ricerca psicocognitiva. Varie sono le ragioni di tale separazione. Da parte logico-filosofica è stata prevalente la preoccupazione di rispettare certe intuizioni riguardanti alcuni usi paradigmatici del condizionale e di soddisfare naturali esigenze di adeguatezza teorica. Da parte psicologica è stata soprattutto perseguita l’adeguatezza descrittiva rispetto agli usi effettivi dei condizionali o ad ampie classi di tali usi. La separazione non ha implicato assenza di reciproche influenze o di punti di contatto. Ad esempio, Johnson-Laird e Byrne (1991; 2002) hanno elaborato una versione psicologica del condizionale materiale della logica classica allo scopo di dare una spiegazione degli usi dei condizionali indicativi. D’altra parte, logici e filosofi come Ramsey (1990) e Quine (1952) hanno di fatto formulato, anche se non sviluppato, delle vere e proprie ipotesi riguardo all’uso comune degli enunciati condizionali e, nel caso di Ramsey, anche riguardo ai processi mentali soggiacenti. Il presente lavoro ha preso le mosse dall’idea di mettere alla prova quella parte della teoria dei modelli mentali (TMM) che Johnson-Laird e Byrne hanno elaborato riguardo agli enunciati condizionali. L’analisi di una difficoltà riscontrata in tale teoria ha portato ad individuare come caratteristica del condizionale, o, più esattamente di molti suoi proferimenti, l’enfasi che si pone sull’antecedente quando lo si usa nell’asserzione. Il lavoro è proseguito con un’analisi del ruolo dell’antecedente, che ha avuto come esito l’individuazione di due diversi tipi di asserzioni di forma condizional

Gene by gender interplay in moral choices

While philosophers, psychologists and cognitive scientists have proposed distinct definitions of moral judgment, recent studies suggest that moral choices are modulated by neurobiological mechanisms. The pioneering works by Greene showed that certain brain areas may be considered “specific” for moral decision and provided support for a dual-process theory, according to which two different patterns of neural activity are involved in moral choices: a fast, unconscious "emotional" system, and a slow, conscious "cognitive" system1, 2, 3. Furthermore, genetic associations between two allelic variants in serotonin transporter and oxytocin receptor genes, and moral judgment have been reported4, 5. Because of their described association with impulsive behavior6, 7, 8, 9, we questioned whether four polymorphisms in genes involved in serotonergic and dopaminergic neurotransmission (SLC6A3–VNTR, DRD4-VNTR, DRD4 rs1800955, COMT rs4680) would modulate the cognitive and emotional processes at the basis of controversial moral choices. After signing an informed consent, 200 (102F) University students were recruited in a moral dilemma paradigm (N=56) designed to assess three variables: moral action type (Means vs Side Effect), life expectancy (Normal vs Reduced), self-involvement (Involvement vs Non-Involvement). They also provided saliva samples for DNA collection and completed the Impulsivity-Venturesomeness-Empathy Questionnaire (I7). Significant differences between males and females were observed in the I7 scale scores. Moreover, only in males Venturesomeness scores correlated with the number of utilitarian responses. Males, compared to females, gave a higher number of utilitarian responses, showed longer response times for non-utilitarian answers and judged as more acceptable the endorsed moral actions. Interestingly, only females showed a significant association between allelic variants involved in dopamine level regulation in striatum and prefrontal cortex, and moral choices. Our results are the first ones showing that impulsivity and genetic profile influence moral judgment in a gender-related manner, thus shedding new light on the neurobiological mechanisms underlying moral choices. BIBLIOGRAPHY 1. Greene JD, Sommerville RB, Nystrom LE, Darley JM, Cohen JD (2001). An fMRI investigation of emotional engagement in moral judgment. Science 293(5537): 2105–2108. 2. Greene JD, Nystrom LE, Engell AD, Darley JM, Cohen JD (2004). The neural bases of cognitive conflict and control in moral judgment. Neuron 44(2): 389–400. 3. Greene JD (2009). Dual-process morality and the personal/impersonal distinction: a reply to McGuire, Langdon, Coltheart, and Mackenzie. J Exp Soc Psychol 45(3): 581-584. 4. Marsh AA, Crowe SL, Yu HH, Gorodetsky EK, Goldman D, Blair RJR (2011). Serotonin transporter genotype (5-HTTLPR) predicts utilitarian moral judgments. Plos One 6(10): e25148. 5. Walter NT, Montag C, Markett S, Felten A, Voigt G, Reuter M (2012). Ignorance is no excuse: moral judgments are influenced by a genetic variation on the oxytocin receptor gene. Brain and Cognition 78(3): 268-273. 6. Munafò MR, Yalcin B, Willis-Owen SA, Flint J (2008). Association of the dopamine D4 receptor (DRD4) gene and approach-related personality traits: meta-analysis and new data. Biol Psychiatry 63(2): 197-206. 7. Joyce PR, McHugh PC, Light KJ, Rowe S, Miller AL, Kennedy MA (2009). Relationships between angry-impulsive personality traits and genetic polymorphisms of the dopamine transporter. Biol Psychiatry 66(8): 717-721. 8. Reiner I, Spangler G (2011). Dopamine D4 receptor exon III polymorphism, adverse life events and personality traits in a nonclinical German adult sample. Neuropsychobiology 63(1): 52-58. 9. Soeiro-De-Souza MG, Stanford MS, Bio DS, Machado-Vieira R, Moreno RA (2013). Association of the COMT Met158 allele with trait impulsivity in healthy young adult. Mol Med Rep 7(4): 1067-1072