Alterations in Brain Activity Induced by Transcranial Magnetic Stimulation and Their Relation to Decision Making.

Understanding the intricate dynamics between conscious choice and neural processes is crucial for unraveling the complexity of human decision-making. This study investigates the effects of inhibitory Transcranial Magnetic Stimulation (TMS) on choice bias, shedding light on the malleability of cognitive-motor functions involved in decisions. While reaction times remained unaffected, inhibitory TMS to either the left or right motor cortex led to a significant bias in screen side preference during a choice task. These findings suggest that our cognitive-motor processes underlying decision-making can be unconsciously influenced by TMS. Furthermore, analysis of choice attribution categories revealed individual variability, emphasizing the complex nature of the decision-making process. These insights contribute to the ongoing exploration of the neural mechanisms governing human choice. As the neural basis of free will continues to captivate scientific inquiry, this research advances our understanding of the intricate relationship between neural circuits and conscious intention.

Oh it's me again: Déjà vu, the brain, and self-awareness.

Déjà vu and involuntary autobiographical memories (IAMs) are differentiated by a number of factors including metacognition. In contrast to IAMs, déjà vu activates regions associated with self-awareness including the right dorsolateral prefrontal cortex.

The Neural Correlates of Narcissism: Is There a Connection with Desire for Fame and Celebrity Worship?

(1) Objective: Narcissism is characterized by emotional regulation deficits, a lack of empathy for others, and extreme self-focus. Narcissism has also been linked to an increased desire for fame and celebrity worship. Here, the neuroscience underlying narcissism is examined in order to determine what regions and networks of the brain are altered when non-narcissistic individuals are compared to participants with both grandiose and vulnerable narcissism. (2) Methods: The behavioral relationships between grandiose narcissism and desire for fame and vulnerable narcissism and celebrity worship are explored, along with a possible relationship at the neural level between these constructs. In this paper, we review research demonstrating that increased levels of grandiose narcissism are associated with an increase in obsession with fame, while vulnerable narcissism is associated with celebrity worship. (3) Results: Based on current data, the frontal regions underlie narcissism and also likely underlie celebrity worship and desire for fame. This tenuous conclusion is based on a limited number of studies. (4) Conclusions: The brain areas associated with grandiose narcissism may be associated with an intense desire for fame as well, while brain regions associated with vulnerable narcissism may be similar in celebrity worshipers. Future research studies on the brain that are specifically designed to test these relationships at a neurological level are needed.

Excitatory Dorsal Lateral Prefrontal Cortex Transcranial Magnetic Stimulation Increases Social Anxiety.

Social exclusion refers to the experience of rejection by one or more people during a social event and can induce pain-related sensations. Cyberball, a computer program, is one of the most common tools for analyzing social exclusion. Regions of the brain that underlie social pain include networks linked to the dorsal lateral prefrontal cortex (DLPFC). Specifically, self-directed negative socially induced exclusion is associated with changes in DLPFC activity. Direct manipulation of this area may provide a better understanding of how the DLPFC can influence the perception of social exclusion and determine a causal role of the DLPFC. Transcranial magnetic stimulation (TMS) was applied to both the left and right DLPFC to gauge different reactions to the Cyberball experience. It was found that there were elevated exclusion indices following right DLPFC rTMS; participants consistently felt more excluded when the right DLPFC was excited. This may relate to greater feelings of social pain when the right DLPFC is manipulated. These data demonstrate that direct manipulation of the DLPFC results in changes in responses to social exclusion.

Self-Enhancement and the Medial Prefrontal Cortex: The Convergence of Clinical and Experimental Findings.

Self-enhancement (SE) is often overlooked as a fundamental cognitive ability mediated via the Prefrontal Cortex (PFC). Here, we present research that establishes the relationship between the PFC, SE, and the potential evolved beneficial mechanisms. Specifically, we believe there is now enough evidence to speculate that SE exists to provide significant benefits and should be considered a normal aspect of the self. Whatever the metabolic or social cost, the upside of SE is great enough that it is a core and fundamental psychological construct. Furthermore, though entirely theoretical, we suggest that a critical reason the PFC has evolved so significantly in Homo sapiens is to, in part, sustain SE. We, therefore, elaborate on its proximate and ultimate mechanisms.

Employing Transcranial Magnetic Stimulation in a Resource Limited Environment to Establish Brain-Behavior Relationships.

Neuroimaging is typically perceived as a resource demanding discipline. While this is the case in certain circumstances, institutions with limited resources have historically contributed significantly to the field of neuroscience, including neuroimaging. In the study of self-deception, we have successfully employed single-pulse TMS to determine the brain correlates of abilities including overclaiming and self-enhancement. Even without the use of neuro-navigation, methods provided here lead to successful outcomes. For example, it was discovered that decreases in self-deceptive responding lead to a decrease in affect. These methods provide data that are reliable and valid, and such methods provide research opportunities otherwise unavailable. Through the use of these methods, the overall knowledge base in the field of neuroscience is expanded, providing research opportunities to students such as those at our institution (Montclair State University is a Hispanic-Serving Institute) who are often denied such research experiences.

Self-Conscious Emotions and the Right Fronto-Temporal and Right Temporal Parietal Junction.

For more than two decades, research focusing on both clinical and non-clinical populations has suggested a key role for specific regions in the regulation of self-conscious emotions. It is speculated that both the expression and the interpretation of self-conscious emotions are critical in humans for action planning and response, communication, learning, parenting, and most social encounters. Empathy, Guilt, Jealousy, Shame, and Pride are all categorized as self-conscious emotions, all of which are crucial components to one's sense of self. There has been an abundance of evidence pointing to the right Fronto-Temporal involvement in the integration of cognitive processes underlying the expression of these emotions. Numerous regions within the right hemisphere have been identified including the right temporal parietal junction (rTPJ), the orbitofrontal cortex (OFC), and the inferior parietal lobule (IPL). In this review, we aim to investigate patient cases, in addition to clinical and non-clinical studies. We also aim to highlight these specific brain regions pivotal to the right hemispheric dominance observed in the neural correlates of such self-conscious emotions and provide the potential role that self-conscious emotions play in evolution.

Corticospinal Excitability during a Perspective Taking Task as Measured by TMS-Induced Motor Evoked Potentials.

Only by understanding the ability to take a third-person perspective can we begin to elucidate the neural processes responsible for one's inimitable conscious experience. The current study examined differences in hemispheric laterality during a first-person perspective (1PP) and third-person perspective (3PP) taking task, using transcranial magnetic stimulation (TMS). Participants were asked to take either the 1PP or 3PP when identifying the number of spheres in a virtual scene. During this task, single-pulse TMS was delivered to the motor cortex of both the left and right hemispheres of 10 healthy volunteers. Measures of TMS-induced motor-evoked potentials (MEPs) of the contralateral abductor pollicis brevis (APB) were employed as an indicator of lateralized cortical activation. The data suggest that the right hemisphere is more important in discriminating between 1PP and 3PP. These data add a novel method for determining perspective taking and add to the literature supporting the role of the right hemisphere in meta representation.

The medial prefrontal cortex: a potential link between self-deception and affect.

The Medial Prefrontal Cortex (MPFC) is crucial for normal social functioning in humans. Because of its involvement in social monitoring, self-awareness, and self-enhancement, the MPFC may be critical to buffering negative affect and establishing a positive self-esteem. For example, we have previously found that disruption of the MPFC leads to more honest responses, which implies that the MPFC may be critically involved in self-deception. We therefore hypothesized that disrupting the MPFC would lead to a decrease in affect. Employing a virtual lesion TMS (Transcranial Magnetic Stimulation) technique, we disrupted the MPFC while participants rated their mood based on two anchor affect terms. During TMS, the participants rated their current emotional mental state. Compared to sham TMS, it was found that mood was reduced immediately following single-pulse MPFC stimulation. The results supported the hypothesis the MPFC mood reduction occurs when the MPFC is disrupted. Because this study replicated the conditions employed in previous self-deception studies, we suggest that the results may indicate that lack of self-enhancement may lead to a decrease in mood. Further studies should examine this possibility.

Preliminary Evidence of the Role of Medial Prefrontal Cortex in Self-Enhancement: A Transcranial Magnetic Stimulation Study.

Humans employ a number of strategies to improve their position in their given social hierarchy. Overclaiming involves presenting oneself as having more knowledge than one actually possesses, and it is typically invoked to increase one's social standing. If increased expectations to possess knowledge is a perceived social pressure, such expectations should increase bouts of overclaiming. As the medial prefrontal cortex (MPFC) is sensitive to social pressure and disruption of the MPFC leads to decreases in overclaiming, we predicted that transcranial magnetic stimulation (TMS) applied to the MPFC would reduce overclaiming and the effects would be enhanced in the presence of social pressure. Twelve participants were given a test in which half of the words were real and half were fake, and they were asked how well they knew each word. They were not told that any of the words were fake. Half of the participants were exposed to social pressure while the other half were not. Following TMS delivered to the MPFC, overclaiming rates decreased, specifically under conditions of high social pressure. Medial PFC TMS did not influence real word responses and real words did not interact with the MPFC and social pressure. These preliminary findings support the significant role the MPFC plays in social cognition and the importance of the MPFC in mediating socially meaningful situations. We suggest the role of the MPFC as being highly influenced by the premium placed on social manipulation in human evolution.

Overclaiming and the medial prefrontal cortex: A transcranial magnetic stimulation study.

The tendency to claim more knowledge than one actually has is common and well documented; however, little research has focused on the neural mechanisms that underlie this phenomenon. The goal of the present study was to investigate the cortical correlates of overclaiming. Transcranial magnetic stimulation (TMS) was delivered to the medial prefrontal cortex (MPFC), supplementary motor area, and precuneus during the presentation of a series of words that participants were told made up a cultural IQ test. However, participants were not informed that 50% of the words were actually fabricated. False claiming was reduced following MPFC TMS. Furthermore, reaction time decreases following MPFC TMS indicated that participants engaged in less reflection during the task, suggesting a potential reduction in social monitoring of behavior.

The effect of deception on motor cortex excitability.

Although a number of recent neuroimaging studies have examined the relationship between the brain and deception, the neurological correlates of deception are still not well understood. The present study sought to assess differences in cortical excitability during the act of deception by measuring motor evoked potentials (MEPs) during transcranial magnetic stimulation (TMS). Sports fanatics and low-affiliation sports fans were presented with preferred and rival team images and were asked to deceptively or honestly identify their favored team. Hemispheric differences were found including greater excitability of the left motor cortex during the generation of deceptive responses. In contrast to current physiological measures of deception, level of arousal was not found to differentiate truthful and deceptive responses. The results are presented in terms of a complex cognitive pattern contributing to the generation of deceptive responses.

Investigations of hemispheric specialization of self-voice recognition.

Three experiments investigated functional asymmetries related to self-recognition in the domain of voices. In Experiment 1, participants were asked to identify one of three presented voices (self, familiar or unknown) by responding with either the right or the left-hand. In Experiment 2, participants were presented with auditory morphs between the self-voice and a familiar voice and were asked to perform a forced-choice decision on speaker identity with either the left or the right-hand. In Experiment 3, participants were presented with continua of auditory morphs between self- or a familiar voice and a famous voice, and were asked to stop the presentation either when the voice became "more famous" or "more familiar/self". While these experiments did not reveal an overall hand difference for self-recognition, the last study, with improved design and controls, suggested a right-hemisphere advantage for self-compared to other-voice recognition, similar to that observed in the visual domain for self-faces.

In-game fatigue influences concussions in national hockey league players.

The number of concussions and other head injuries are increasing in the National Hockey League (NHL). The factors that may influence concussion risk in hockey remain largely unknown. In the current study, data on 787 NHL players from the 2001-2002 season were examined. It was found that a player's average ice time per game was a significant predictor of concussion. A player's total ice time for the season was not a significant predictor, however, and there was no significant difference found in the number of games played in the season between those who suffered a concussion and those who did not. These data suggest that in-game fatigue is an important factor when considering concussions.

Elucidating the neural correlates of egoistic and moralistic self-enhancement.

Self-enhancement is the biasing of one's view of oneself in a positive direction. The brain correlates of self-enhancement remain unclear though it has been reported that the medial prefrontal cortex (MPFC) may be important for producing self-enhancing responses. Previous studies have not examined whether the neural correlates of self-enhancement depend on the particular domain in which individuals are enhancing themselves. Both moralistic and egoistic words were presented to participants while transcranial magnetic stimulation (TMS) was applied to the MPFC, precuneus or in a sham orientation. Participants were asked to make decisions as to the words describing themselves, some of which were positive and some of which were negative. It was found the MPFC TMS significantly disrupted egoistic self-enhancement when TMS was delivered to the MPFC. Judgments involving moralistic words were not influenced by TMS. These data provide further evidence that MPFC is involved in self-enhancement, and that the role of MPFC may be selective in this regard.

Assessing the neural correlates of self-enhancement bias: a transcranial magnetic stimulation study.

Considerable research has focused on overly positive self-perceptions (self-enhancement), and yet little is known about the underlying neural mechanisms. The present study sought to assess the neural correlates of self-enhancement by applying Transcranial Magnetic Stimulation (TMS) to three brain regions. Twelve participants rated their best friend, as well as the self on a set of desirable or undesirable traits while TMS pulses were delivered in a virtual lesion manner. During the baseline condition (Sham TMS), participants produced more desirable and fewer undesirable ratings for themselves as compared to their best friend, showing self-enhancement. Compared to Sham TMS, TMS delivered to the Medial Prefrontal Cortex (MPFC) reduced self-enhancement whereas TMS delivered to the Supplementary Motor Area (SMA) and the precuneus did not. Together, these findings suggest that the MPFC may influence self-enhancement.

The self and social cognition: the role of cortical midline structures and mirror neurons.

Recent evidence suggests that there are at least two large-scale neural networks that represent the self and others. Whereas frontoparietal mirror-neuron areas provide the basis for bridging the gap between the physical self and others through motor-simulation mechanisms, cortical midline structures engage in processing information about the self and others in more abstract, evaluative terms. This framework provides a basis for reconciling findings from two separate but related lines of research: self-related processing and social cognition. The neural systems of midline structures and mirror neurons show that self and other are two sides of the same coin, whether their physical interactions or their most internal mental processes are examined.