scholarly journals GABA Boosts Relief from Coercive Power: an fMRI study

2021 ◽  
Author(s):  
Yawei Cheng ◽  
Róger Martínez ◽  
Yu-Chun Chen ◽  
Yang-Teng Fan ◽  
Chenyi Chen
Keyword(s):  
Reaction Times ◽  
Coercive Power ◽  
Gamma Aminobutyric Acid ◽  
Subjective Ratings ◽  
Temporoparietal Junction ◽  
Perceived Coercion ◽  
Fmri Study ◽  
Helping Others ◽  
Dorsolateral Prefrontal ◽  
Right Temporoparietal Junction

Abstract Individuals under coercive control frequently suffer from anxiety, with recent research asserting this situation as a catalyst for certain types of violence directed towards those suffering under the most serious and insidious forms of coercive power –such as domestic violence victims. Studies researching this matter have skewed towards dissembling manipulation, or participants' obedience levels, neglecting the fact that agents under coercive power are also victims of coercive violence. In this functional magnetic resonance imaging (fMRI) study, we investigate the effects of the anxiolytic GABAA (gamma-Aminobutyric acid) modulator, lorazepam, on behavioral and neural levels in response to coercive power. We used a virtual obedience to authority paradigm inspired in Milgram's renowned experiments of the same nature. An experimenter ordered a volunteer to press a handheld button to initiate actions that carry different moral consequences, including harming or helping others. Our results showed that lorazepam administration, relative to placebo, slowed down reaction times when initiating harming behaviors, but accelerated reaction times for helping actions, despite comparable subjective ratings regarding perceived coercion. Coercive harming significantly increased activation in the amygdala, hippocampus, orbitofrontal cortex, and dorsolateral prefrontal cortex (dlPFC). After lorazepam administration, activity in the amygdala and hippocampus decreased, but activity in the dlPFC and right temporoparietal junction increased. The lower activity in the hippocampus predicted higher subjective ratings for perceived coercion. Furthermore, lorazepam administration significantly decreased the functional connectivity of the hippocampus with the dlPFC during coercive harming. Our results shed light on the coping strategies against coercion beyond merely examining its effects.

scholarly journals Bilateral (but not unilateral) interaction creates and cements norms at the covert psychophysical level: A behavioral and an fMRI study

2020 ◽  
Author(s):  
Kiri Kuroda ◽  
Yukiko Ogura ◽  
Akitoshi Ogawa ◽  
Tomoya Tamei ◽  
Kazushi Ikeda ◽  
...  
Keyword(s):  
Social Norms ◽  
Behavioral Experiment ◽  
Estimation Task ◽  
Temporoparietal Junction ◽  
Dorsomedial Prefrontal Cortex ◽  
Computer Agent ◽  
Fmri Study ◽  
Right Temporoparietal Junction ◽  
Simple Estimation ◽  
The Stability

Social norms, including values, beliefs and even perceptions about the world, are preserved and created through repeated interactions between individuals. However, whereas neuro-cognitive research on social norms has used the “unilateral influence” paradigm focusing on people’s reactions to extant standards, little is known about how our basic perceptions and judgments are shaped as new norms through bilateral interaction. Here, using a simple estimation task, we investigated the formation of perceptual norms using two experiments coupled with computational modeling. In the behavioral experiment, participants in dyads repeatedly estimated the number of dots on a screen and viewed each other’s answers. In the fMRI experiment, we manipulated the interaction process by pairing each participant with a computer agent which adjusted its estimations reciprocally to participants’ estimations (bilateral agent) or did not (unilateral). The results indicated that only the bilateral interaction yielded convergence of participants’ covert psychophysical functions (relations between subjective estimations and the actual number of dots) as well as overt behavioral responses within a pair. Bilateral interaction also increased the stability (reliability) of the covert function within each individual after interaction. Neural activity in the mentalizing network (right temporoparietal junction and dorsomedial prefrontal cortex) during interaction modulated the stabilization of the psychophysical function. These results imply that bilateral interaction helps people to cognitively anchor their views with each other. Such spontaneous perspective sharing can yield a shared covert “generative model” that enables endogenous agreement on totally new targets ― one of the key features of social norms.

scholarly journals When implicit prosociality trumps selfishness: the neural valuation system underpins more optimal choices when learning to avoid harm to others than to oneself

2020 ◽  
Author(s):  
Lukas Lengersdorff ◽  
Isabella Wagner ◽  
Claus Lamm
Keyword(s):  
Neural Mechanisms ◽  
Temporoparietal Junction ◽  
Fmri Study ◽  
The Social ◽  
Egocentric Bias ◽  
Right Temporoparietal Junction ◽  
Increased Sensitivity ◽  
Self Harm ◽  
Human Participants ◽  
The Right

Humans learn quickly which actions cause them harm. As social beings, we also need to learn to avoid actions that hurt others. It is currently unknown if humans are as good at learning to avoid others' harm (prosocial learning) as they are at learning to avoid self-harm (self-relevant learning). Moreover, it remains unclear how the neural mechanisms of prosocial learning differ from those of self-relevant learning. In this fMRI study, 96 male human participants learned to avoid painful stimuli either for themselves or for another individual. We found that participants performed more optimally when learning for the other than for themselves. Computational modeling revealed that this could be explained by an increased sensitivity to subjective values of choice alternatives during prosocial learning. Increased value-sensitivity was further associated with empathic traits. On the neural level, higher value-sensitivity during prosocial learning was associated with stronger engagement of the ventromedial prefrontal cortex (VMPFC) during valuation. Moreover, the VMPFC exhibited higher connectivity with the right temporoparietal junction during prosocial, compared to self-relevant, choices. Our results suggest that humans are particularly adept at learning to protect others from harm. This ability appears implemented by neural mechanisms overlapping with those supporting self-relevant learning, but with the additional recruitment of structures associated to the social brain. Our findings contrasts with recent proposals that humans are egocentrically biased when learning to obtain monetary rewards for self or others. Prosocial tendencies may thus trump the egocentric bias in learning when another person's physical integrity is at stake.

scholarly journals Neural basis of corruption in power-holders

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Yang Hu ◽  
Chen Hu ◽  
Edmund Derrington ◽  
Brice Corgnet ◽  
Chen Qu ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Third Party ◽  
Neural Basis ◽  
Temporoparietal Junction ◽  
Dorsolateral Prefrontal ◽  
Power Holder ◽  
Right Temporoparietal Junction ◽  
Moral Cost ◽  
The Right ◽  
The Cost

Corruption often involves bribery, when a briber suborns a power-holder to gain advantages usually at a cost of moral transgression. Despite its wide presence in human societies, the neurocomputational basis of bribery remains elusive. Here, using model-based fMRI, we investigated the neural substrates of how a power-holder decides to accept or reject a bribe. Power-holders considered two types of moral cost brought by taking bribes: the cost of conniving with a fraudulent briber, encoded in the anterior insula, and the harm brought to a third party, represented in the right temporoparietal junction. These moral costs were integrated into a value signal in the ventromedial prefrontal cortex. The dorsolateral prefrontal cortex was selectively engaged to guide anti-corrupt behaviors when a third party would be harmed. Multivariate and connectivity analyses further explored how these neural processes depend on individual differences. These findings advance our understanding of the neurocomputational mechanisms underlying corrupt behaviors.

scholarly journals Effects of ketamine on brain function during metacognition of episodic memory

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Mirko Lehmann ◽  
Claudia Neumann ◽  
Sven Wasserthal ◽  
Johannes Schultz ◽  
Achilles Delis ◽  
...  
Keyword(s):  
Episodic Memory ◽  
Parietal Lobe ◽  
Memory Task ◽  
Reaction Times ◽  
Neural Correlates ◽  
Double Blind ◽  
Lingual Gyrus ◽  
States Of Consciousness ◽  
Fmri Study ◽  
Confidence Ratings

Abstract Only little research has been conducted on the pharmacological underpinnings of metacognition. Here, we tested the modulatory effects of a single intravenous dose (100 ng/ml) of the N-methyl-D-aspartate-glutamate-receptor antagonist ketamine, a compound known to induce altered states of consciousness, on metacognition and its neural correlates. Fifty-three young, healthy adults completed two study phases of an episodic memory task involving both encoding and retrieval in a double-blind, placebo-controlled fMRI study. Trial-by-trial confidence ratings were collected during retrieval. Effects on the subjective state of consciousness were assessed using the 5D-ASC questionnaire. Confirming that the drug elicited a psychedelic state, there were effects of ketamine on all 5D-ASC scales. Acute ketamine administration during retrieval had deleterious effects on metacognitive sensitivity (meta-d′) and led to larger metacognitive bias, with retrieval performance (d′) and reaction times remaining unaffected. However, there was no ketamine effect on metacognitive efficiency (meta-d′/d′). Measures of the BOLD signal revealed that ketamine compared to placebo elicited higher activation of posterior cortical brain areas, including superior and inferior parietal lobe, calcarine gyrus, and lingual gyrus, albeit not specific to metacognitive confidence ratings. Ketamine administered during encoding did not significantly affect performance or brain activation. Overall, our findings suggest that ketamine impacts metacognition, leading to significantly larger metacognitive bias and deterioration of metacognitive sensitivity as well as unspecific activation increases in posterior hot zone areas of the neural correlates of consciousness.

scholarly journals Do Empathic Individuals Behave More Prosocially? Neural Correlates for Altruistic Behavior in the Dictator Game and the Dark Side of Empathy

2021 ◽  
Vol 11 (7) ◽  
pp. 863
Author(s):  
Michael Schaefer ◽  
Anja Kühnel ◽  
Franziska Rumpel ◽  
Matti Gärtner
Keyword(s):  
Dictator Game ◽  
Empathic Concern ◽  
Dark Side ◽  
Altruistic Behavior ◽  
Temporoparietal Junction ◽  
Specific Effects ◽  
Significant Relationships ◽  
Right Temporoparietal Junction ◽  
Neural Underpinnings ◽  
The Right

Do empathic individuals behave more prosocially? When we think of highly empathic individuals, we tend to assume that it is likely that those people will also help others. Most theories on empathy reflect this common understanding and claim that the personality trait empathy includes the willingness to help others, but it remains a matter of debate whether empathic individuals really help more. In economics, a prominent demonstration that our behavior is not always based on pure self-interest is the Dictator Game, which measures prosocial decisions in an allocation task. This economic game shows that we are willing to give money to strangers we do not know anything about. The present study aimed to test the relationship between dispositional empathy and prosocial acting by examining the neural underpinnings of prosocial behavior in the Dictator Game. Forty-one participants played different rounds of the Dictator Game while being scanned with functional magnetic resonance imaging (fMRI). Brain activation in the right temporoparietal junction area was associated with prosocial acting (number of prosocial decisions) and associated with empathic concern. Behavioral results demonstrated that empathic concern and personal distress predicted the number of prosocial decisions, but in a negative way. Correlations with the amount of money spent did not show any significant relationships. We discuss the results in terms of group-specific effects of affective empathy. Our results shed further light on the complex behavioral and neural mechanisms driving altruistic choices.

scholarly journals The effect of high-frequency rTMS of the left dorsolateral prefrontal cortex on the resolution of response, semantic and task conflict in the colour-word Stroop task

2021 ◽  
Author(s):  
Benjamin A. Parris ◽  
Michael G. Wadsley ◽  
Gizem Arabaci ◽  
Nabil Hasshim ◽  
Maria Augustinova ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Task Performance ◽  
Stroop Task ◽  
Word Reading ◽  
Reaction Times ◽  
Task Conflict ◽  
General Effect ◽  
Task Set ◽  
Left Dlpfc ◽  
Dorsolateral Prefrontal

AbstractPrevious work investigating the effect of rTMS of left Dorso-Lateral Prefrontal Cortex (DLPFC) on Stroop task performance reports no changes to the Stroop effect but reduced reaction times on both congruent and incongruent trials relative to sham stimulation; an effect attributed to an enhanced attentional (or task) set for colour classification. The present study tested this account by investigating whether, relative to vertex stimulation, rTMS of the left DLPFC modifies task conflict, a form of conflict that arises when task sets for colour classification and word reading compete, given that this particular type of conflict would be reduced by an enhanced task set for colour classification. Furthermore, the present study included measures of other forms of conflict present in the Stroop task (response and semantic conflict), the potential effects on which would have been hidden in previous studies employing only incongruent and congruent stimuli. Our data showed that left DLPFC stimulation had no effect on the magnitude of task conflict, nor did it affect response, semantic or overall conflict (where the null is supported by sensitive Bayes Factors in most cases). However, consistent with previous research left DLPFC stimulation had the general effect of reducing reaction times. We, therefore, show for the first time that relative to real vertex stimulation left DLPFC stimulation does not modify Stroop interference. Alternative accounts of the role of the left DLPFC in Stroop task performance in which it either modifies response thresholds or facilitates responding by keeping the correct response keys active in working memory are discussed.

Resting-state Functional Connectivity of the Right Temporoparietal Junction Relates to Belief Updating and Reorienting during Spatial Attention

2020 ◽  
Vol 32 (6) ◽  
pp. 1130-1141
Author(s):  
Anne-Sophie Käsbauer ◽  
Paola Mengotti ◽  
Gereon R. Fink ◽  
Simone Vossel
Keyword(s):  
Functional Connectivity ◽  
Cognitive Processing ◽  
Resting State ◽  
Prior Information ◽  
Dependent Manner ◽  
Resting State Functional Connectivity ◽  
Belief Updating ◽  
Temporoparietal Junction ◽  
Right Temporoparietal Junction ◽  
The Right

Although multiple studies characterized the resting-state functional connectivity (rsFC) of the right temporoparietal junction (rTPJ), little is known about the link between rTPJ rsFC and cognitive functions. Given a putative involvement of rTPJ in both reorienting of attention and the updating of probabilistic beliefs, this study characterized the relationship between rsFC of rTPJ with dorsal and ventral attention systems and these two cognitive processes. Twenty-three healthy young participants performed a modified location-cueing paradigm with true and false prior information about the percentage of cue validity to assess belief updating and attentional reorienting. Resting-state fMRI was recorded before and after the task. Seed-based correlation analysis was employed, and correlations of each behavioral parameter with rsFC before the task, as well as with changes in rsFC after the task, were assessed in an ROI-based approach. Weaker rsFC between rTPJ and right intraparietal sulcus before the task was associated with relatively faster updating of the belief that the cue will be valid after false prior information. Moreover, relatively faster belief updating, as well as faster reorienting, were related to an increase in the interhemispheric rsFC between rTPJ and left TPJ after the task. These findings are in line with task-based connectivity studies on related attentional functions and extend results from stroke patients demonstrating the importance of interhemispheric parietal interactions for behavioral performance. The present results not only highlight the essential role of parietal rsFC for attentional functions but also suggest that cognitive processing during a task changes connectivity patterns in a performance-dependent manner.

scholarly journals Automaticity and Reestablishment of Executive Control—An fMRI Study

2006 ◽  
Vol 18 (8) ◽  
pp. 1331-1342 ◽  
Author(s):  
Andrea Kübler ◽  
Veronica Dixon ◽  
Hugh Garavan
Keyword(s):  
Executive Control ◽  
Dorsolateral Prefrontal Cortex ◽  
Search Task ◽  
Visual Search Task ◽  
Cortical Activation ◽  
Automatic Behavior ◽  
Automatic Response ◽  
Fmri Study ◽  
Dorsolateral Prefrontal

The ability to exert control over automatic behavior is of particular importance as it allows us to interrupt our behavior when the automatic response is no longer adequate or even dangerous. However, despite the literature that exists on the effects of practice on brain activation, little is known about the neuroanatomy involved in reestablishing executive control over previously automatized behavior. We present a visual search task that enabled participants to automatize according to defined criteria within about 3 hr of practice and then required them to reassert control without changing the stimulus set. We found widespread cortical activation early in practice. Activation in all frontal areas and in the inferior parietal lobule decreased significantly with practice. Only selected prefrontal (Brodmann's areas [BAs] 9/46/8) and parietal areas (BAs 39/40) were specifically reactivated when executive control was required, underlining the crucial role of the dorsolateral prefrontal cortex in executive control to guide our behavior.

scholarly journals Cognitive Aftereffects of Acute tDCS Coupled with Cognitive Training: An fMRI Study in Healthy Seniors

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
P. Šimko ◽  
M. Pupíková ◽  
M. Gajdoš ◽  
I. Rektorová
Keyword(s):  
Older Adults ◽  
Working Memory ◽  
Cognitive Training ◽  
Brain Network ◽  
Resting State Functional Connectivity ◽  
Double Blind ◽  
Sham Stimulation ◽  
Highly Educated ◽  
Fmri Study ◽  
Dorsolateral Prefrontal

Enhancing cognitive functions through noninvasive brain stimulation is of enormous public interest, particularly for the aging population in whom processes such as working memory are known to decline. In a randomized double-blind crossover study, we investigated the acute behavioral and neural aftereffects of bifrontal and frontoparietal transcranial direct current stimulation (tDCS) combined with visual working memory (VWM) training on 25 highly educated older adults. Resting-state functional connectivity (rs-FC) analysis was performed prior to and after each stimulation session with a focus on the frontoparietal control network (FPCN). The bifrontal montage with anode over the left dorsolateral prefrontal cortex enhanced VWM accuracy as compared to the sham stimulation. With the rs-FC within the FPCN, we observed significant stimulation × time interaction using bifrontal tDCS. We found no cognitive aftereffects of the frontoparietal tDCS compared to sham stimulation. Our study shows that a single bifrontal tDCS combined with cognitive training may enhance VWM performance and rs-FC within the relevant brain network even in highly educated older adults.

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