Biology subjects

Derrington, E.

Publications and source records attributed to Derrington, E..

5 recordsLinked to original sources

bioRxiv2024

Dynamic valuation bias explains social influence on cheating behavior

Observing immoral behavior increases ones dishonesty by social influence and learning processes. The neurocomputational mechanisms underlying such moral contagion remain unclear. We tested different mechanistic hypotheses to account for moral contagion. We used model-based fMRI and a new cheating game in which participants were sequentially placed in honest and dishonest social norm contexts. Participants cheating behavior increased in the dishonest norm context but was unchanged in the honest. The best model to account for behavior indicated that participants valuation was dynamically biased by learning that others had cheated. At the time of choice, the internalization of social norms was implemented in the lateral prefrontal cortex and biased valuations of cheating. During learning, simulation of others cheating behavior was encoded in the posterior superior temporal sulcus. Together, these findings provide a mechanistic understanding of how learning about others dishonesty biases individuals valuation of cheating but does not alter ones established preferences. Significance statementSocial influence is at the root of human behavior. For example, we tend to follow others bad moral behavior such as cheating. Here, we explore the neuro-computational mechanisms of social influence on cheating behavior. We validated a new model capturing both how we learn about others (dis)honesty and how this bias our choice. We show that if we observe dishonest others we tend to be more dishonest ourselves. This behavioral change is driven by a bias dynamically changing with our knowledge about the others cheating behavior. Neurally, we found that the lateral prefrontal cortex implements this bias into the decision process while the posterior superior temporal sulcus and the temporo-parietal junction encode our learned representation of others cheating.

neuroscience↗

bioRxiv2023

Causal Role of the Medial Prefrontal Cortex in Learning Social Hierarchy

Social hierarchy is a fundamental principle of social organization and an important attribute of community stability and development. Yet, little is known about the causal role of specific brain regions in learning hierarchies. Here, using transcranial direct current stimulation (tDCS), we investigated the causal role of the medial prefrontal cortex (mPFC) in learning social and non-social hierarchies. In the Training phase, participants(N=128) acquired knowledge of social and non-social hierarchy in parallel, by trial and error. During the Test phase, they were presented with two items from hierarchies that were never encountered together and required to make transitive inferences. Anodal stimulation over mPFC impaired social hierarchy learning compared with non-social learning and this modulation was influenced by the relative social rank of the members (i.e. higher or lower status). Anodal stimulation also impaired transitive inference making, but only during early blocks before learning was established. Together, our results provide causal evidence of mPFC engagement in learning social ranks by observation.

neuroscience↗

bioRxiv2022

ERPs responses to dominance features from human faces

Social dominance is an important feature of social life. Dominance has been proposed to be one of two trait dimensions underpinning social judgments of human faces. Yet, the neural bases of the ability to identify different dominance levels in others based on facial features remains poorly understood. Here, we used event-related potentials (ERPs) to determine the temporal dynamics of facial dominance evaluation based on facial features signaling physical strength/weakness in humans. Twenty-seven participants performed a dominance perception task where they passively viewed faces with different dominance levels. Dominance levels did not modulate an early component of face processing, known as the N170 component, but did modulate the Late Positive Potential (LPP) component. These findings indicate that participants inferred dominance levels at a late stage of face evaluation. Furthermore, the highest level of dominant faces and the lowest level of submissive faces both elicited higher LPP amplitudes than faces with a neutral dominance level. Taken together, the present study provides new insights regarding the dynamics of the neurocognitive processes underlying facial dominance evaluation.

neuroscience↗

bioRxiv2020

Cognitive regulation of multimodal food perception in the human brain

The ability to regulate appetite is essential to avoid food over-consumption. The desire for a particular food can be triggered by its odor before it is even seen. Using fMRI, we identify the neural systems modulated by cognitive regulation when experiencing appetizing food stimuli presented in both olfactory and visual modalities, while being hungry. Regulatory instruction modulated bids for food items and inhalation patterns. Distinct brain regions were observed for up and down appetite-regulation, respectively the dorsomedial prefrontal cortex (dmPFC) and dorsolateral PFC. Food valuation engaged the ventromedial PFC and bilateral striatum while the amygdala was modulated by individual food preferences, indexed by rank-ordered bids. Furthermore, we identified a neurobiological marker for up-regulating success: individuals with higher blood levels of ghrelin were better at exercising up-regulation, and engaged more the dmPFC. This characterizes the neural circuitry regulating food consumption and suggests potential hormonal and neurofunctional targets for preventing eating disorders.

neuroscience↗

bioRxiv2019

Neurocomputational mechanisms underlying immoral decisions benefiting self or others

Immoral behavior often consists of weighing transgression of a moral norm against maximizing personal profits. One important question is to understand why immoral behaviors vary based on who receives specific benefits and what are the neurocomputational mechanisms underlying such moral flexibility. Here, we used model-based fMRI to investigate how immoral behaviors change when benefiting oneself or someone else. Participants were presented with offers requiring a tradeoff between a moral cost (i.e., profiting a morally bad cause) and a benefit for either oneself or a charity. Participants were more willing to obtain ill-gotten profits for themselves than for a charity, driven by a devaluation of the moral cost when deciding for their own interests. The subjective value of an immoral offer, computed as a linear summation of the weighed monetary gain and moral cost, recruited the ventromedial prefrontal cortex regardless of beneficiaries. Moreover, paralleling the behavioral findings, this region enhanced its functional coupling with mentalizing-related regions while deciding whether to gain morally-tainted profits for oneself vs. charity. Finally, individual differences in moral preference differentially modulated choice-specific signals in the dorsolateral prefrontal cortex according to who benefited from the decisions. These findings provide insights for understanding the neurobiological basis of moral flexibility.

neuroscience↗