Can neural responses of a small group of individuals predict the behavior of large-scale populations? In this investigation, brain activations were recorded while smokers viewed three different television campaigns promoting the National Cancer Institute’s telephone hotline to help smokers quit (1-800-QUIT-NOW). The smokers also provided self-report predictions of the campaigns’ relative effectiveness. Population measures of the success of each campaign were computed by comparing call volume to 1-800-QUIT-NOW in the month before and the month after the launch of each campaign. This approach allowed us to directly compare the predictive value of self-reports with neural predictors of message effectiveness. Neural activity in a medial prefrontal region of interest, previously associated with individual behavior change, predicted the population response, whereas self-report judgments did not. This finding suggests a novel way of connecting neural signals to population responses that has not been previously demonstrated and provides information that may be difficult to obtain otherwise.
mass media; neuroimaging; health; cognitive neuroscience; neuromarketing; health communication; smoking
Self-evaluations undergo significant transformation during early adolescence, developing in parallel with the heightened complexity of teenagers’ social worlds. Intuitive theories of adolescent development, based in part on animal work, suggest that puberty is associated with neural-level changes that facilitate a “social reorientation” (Nelson, Leibenluft, McClure, and Pine, 2005). However, direct tests of this hypothesis using neuroimaging are limited in humans. This longitudinal fMRI study examined neurodevelopmental trajectories associated with puberty, self-evaluations, and the presumed social reorientation during the transition from childhood to adolescence. Participants (N = 27, M age = 10.1 and 13.1 years at timepoints one and two, respectively) engaged in trait evaluations of two targets (the self and a familiar fictional other), across two domains of competence (social and academic). Responses in ventromedial PFC increased with both age and pubertal development during self-evaluations in the social domain, but not in the academic domain. These results suggest changes in social self-evaluations are intimately connected with biology, not just peer contexts, and provide important empirical support for the relationship between neurodevelopment, puberty, and social functioning.
Lonely older adults have increased expression of pro-inflammatory genes as well as increased risk for morbidity and mortality. Previous behavioral treatments have attempted to reduce loneliness and its concomitant health risks, but have had limited success. The present study tested whether the 8-week Mindfulness-Based Stress Reduction (MBSR) program (compared to a Wait-List control group) reduces loneliness and downregulates loneliness-related pro-inflammatory gene expression in older adults (N=40). Consistent with study predictions, mixed effect linear models indicated that the MBSR program reduced loneliness, compared to small increases in loneliness in the control group (treatment condition × time interaction: F(1,35)=7.86, p=.008). Moreover, at baseline, there was an association between reported loneliness and upregulated pro-inflammatory NF-κB-related gene expression in circulating leukocytes, and MBSR downregulated this NF-κB-associated gene expression profile at post-treatment. Finally, there was a trend for MBSR to reduce C Reactive Protein (treatment condition × time interaction: (F(1,33)=3.39, p=.075). This work provides an initial indication that MBSR may be a novel treatment approach for reducing loneliness and related pro-inflammatory gene expression in older adults.
meditation; mindfulness; older adults; aging; loneliness; genetics; gene expression; stress
Behavioral research on emotion regulation thus far has focused on conscious and deliberative strategies such as reappraisal. Neuroscience investigations into emotion regulation have followed suit. However, neuroimaging tools now open the door to investigate more automatic forms of emotion regulation that take place incidentally and potentially outside of participant awareness that have previously been difficult to examine. The present paper reviews studies on the neuroscience of intentional/deliberate emotion regulation and identifies opportunities for future directions that have not yet been addressed. The authors suggest a broad framework for emotion regulation that includes both deliberative and incidental forms. This framework allows insights from incidental emotion regulation to address open questions about existing work, and vice versa. Several studies relevant to incidental emotion regulation are reviewed with the goal of providing an empirical and methodological groundwork for future research. Finally, several theoretical issues for incidental and intentional emotion regulation are discussed.
People rationalize the choices they make when confronted with difficult decisions by claiming they never wanted the option they did not choose. Behavioral studies on cognitive dissonance provide evidence for decision-induced attitude change, but these studies cannot fully uncover the mechanisms driving the attitude change because only pre- and post-decision attitudes are measured, rather than the process of change itself. In the first fMRI study to examine the decision phase in a decision-based cognitive dissonance paradigm, we observed that increased activity in right-inferior frontal gyrus, medial fronto-parietal regions and ventral striatum, and decreased activity in anterior insula were associated with subsequent decision-related attitude change. These findings suggest the characteristic rationalization processes that are associated with decision-making may be engaged very quickly at the moment of the decision, without extended deliberation and may involve reappraisal-like emotion regulation processes.
cognitive dissonance; rationalization; attitudes; decisions; neuroimaging; right inferior frontal gyrus; insula
We used the five weeks leading up to the 2008 presidential election as a backdrop to examine the ways that the brain processes attitudes and beliefs under different circumstances. We examined individual differences in personal issue importance and trait perspective-taking, as well as the temporal context in which attitude representation took place (i.e. number of days until the election). Finally, we examined the extent to which similar or dissimilar processes were recruited when considering the attitudes of political ingroup and outgroup candidates. Brain regions involved in social cognition and theory of mind, and to a lesser extent the limbic system, were modulated by these factors. Higher issue importance led to greater recruitment of neural regions involved in social cognition, across target perspectives. Higher trait perspective-taking was also associated with greater recruitment of several regions involved in social cognition, but differed depending on target perspective; greater activity was observed in prefrontal regions associated with social cognition when considering the perspective of one's own candidate compared with the opponent, and this effect was amplified closer to the election. Taken together, these results highlight ways in which ability and motivational relevance modulate socio-affective processing of the attitudes of others.
functional magnetic resonance imaging; perspective-taking; political; attitudes; ingroup; outgroup
Although persuasive messages often alter people’s self-reported attitudes and intentions to perform behaviors, these self-reports do not necessarily predict behavior change. We demonstrate that neural responses to persuasive messages can predict variability in behavior change in the subsequent week. Specifically, an a priori region of interest (ROI) in medial prefrontal cortex (MPFC) was reliably associated with behavior change (r = 0.49, p < 0.05). Additionally, an iterative cross-validation approach using activity in this MPFC ROI predicted an average 23% of the variance in behavior change beyond the variance predicted by self-reported attitudes and intentions. Thus, neural signals can predict behavioral changes that are not predicted from self-reported attitudes and intentions alone. Additionally, this is the first functional magnetic resonance imaging study to demonstrate that a neural signal can predict complex real world behavior days in advance.
Functional neuroimaging studies have implicated the involvement of the amygdala and ventrolateral prefrontal cortex (vlPFC) in the pathophysiology of bipolar disorder. Hyperactivity in the amygdala and hypoactivity in the vlPFC have been reported in manic bipolar patients scanned during the performance of an affective faces task. Whether this pattern of dysfunction persists during euthymia is unclear. Using functional magnetic resonance imaging (fMRI), 24 euthymic bipolar and 26 demographically matched healthy control subjects were scanned while performing an affective task paradigm involving the matching and labeling of emotional facial expressions. Neuroimaging results showed that, while amygdala activation did not differ significantly between groups, euthymic patients showed a significant decrease in activation of the right vlPFC (BA47) compared to healthy controls during emotion labeling. Additionally, significant decreases in activation of the right insula, putamen, thalamus and lingual gyrus were observed in euthymic bipolar relative to healthy control subjects during the emotion labeling condition. These data, taken in context with prior studies of bipolar mania using the same emotion recognition task, could suggest that amygdala dysfunction may be a state-related abnormality in bipolar disorder, whereas vlPFC dysfunction may represent a trait-related abnormality of the illness. Characterizing these patterns of activation is likely to help in understanding the neural changes related to the different mood states in bipolar disorder, as well as changes that represent more sustained abnormalities. Future studies that assess mood-state related changes in brain activation in longitudinal bipolar samples would be of interest.
bipolar disorder; amygdala; prefrontal cortex; fmri; emotion
Emotion processing deficits are prominent in schizophrenia and exist prior to the onset of overt psychosis. However, developmental trajectories of neural circuitry subserving emotion regulation and the role that they may play in illness onset have not yet been examined in patients at risk for psychosis. The present study employed a cross-sectional analysis to examine age-related functional activation in amygdala and prefrontal cortex, as well as functional connectivity between these regions, in adolescents at clinical high risk (CHR) for psychosis relative to typically developing adolescents. Participants (n=34) performed an emotion processing fMRI task, including emotion labeling, emotion matching, and non-emotional control conditions. Regression analyses were used to predict activation in the amygdala and ventrolateral prefrontal cortex (vlPFC) based on age, group, sex, and the interaction of age by group. CHR adolescents exhibited altered age-related variation in amygdala and vlPFC activation, relative to controls. Controls displayed decreased amygdala and increased vlPFC activation with age, while patients exhibited the opposite pattern (increased amygdala and decreased vlPFC activation), suggesting a failure of prefrontal cortex to regulate amygdala reactivity. Moreover, a psychophysiological interaction analysis revealed decreased amygdala-prefrontal functional connectivity among CHR adolescents, consistent with disrupted brain connectivity as a vulnerability factor in schizophrenia. These results suggest that the at-risk syndrome is marked by abnormal development and functional connectivity of neural systems subserving emotion regulation. Longitudinal data are needed to confirm aberrant developmental trajectories intra-individually and to examine whether these abnormalities are predictive of conversion to psychosis, and of later deficits in socioemotional functioning.
psychosis; brain development; emotion; amygdala; prefrontal cortex; fMRI
Involvement with friends carries many advantages for adolescents, including protection from the detrimental effects of being rejected by peers. However, little is known about the mechanisms through which friendships may serve their protective role at this age, or the potential benefit of these friendships as adolescents transition to adulthood. As such, this investigation tested whether friend involvement during adolescence related to less neural sensitivity to social threats during young adulthood. Twenty-one adolescents reported the amount of time they spent with friends outside of school using a daily diary. Two years later they underwent an fMRI scan, during which they were ostensibly excluded from an online ball-tossing game by two same-age peers. Findings from region of interest and whole brain analyses revealed that spending more time with friends during adolescence related to less activity in the dorsal anterior cingulate cortex and anterior insula—regions previously linked with negative affect and pain processing—during an experience of peer rejection 2 years later. These findings are consistent with the notion that positive relationships during adolescence may relate to individuals being less sensitive to negative social experiences later on.
adolescence; friendship; peer rejection; functional magnetic resonance imaging
Navigating the social world requires the ability to maintain and manipulate information about people’s beliefs, traits, and mental states. We characterize this capacity as social working memory (SWM). To date, very little research has explored this phenomenon, in part because of the assumption that general working memory systems would support working memory for social information. Various lines of research, however, suggest that social cognitive processing relies on a neurocognitive network (i.e., the “mentalizing network”) that is functionally distinct from, and considered antagonistic with, the canonical working memory network. Here, we review evidence suggesting that demanding social cognition requires SWM and that both the mentalizing and canonical working memory neurocognitive networks support SWM. The neural data run counter to the common finding of parametric decreases in mentalizing regions as a function of working memory demand and suggest that the mentalizing network can support demanding cognition, when it is demanding social cognition. Implications for individual differences in social cognition and pathologies of social cognition are discussed.
mentalizing; working memory; default mode network; social neuroscience; social cognitive affective neuroscience
Methamphetamine abuse is associated with high rates of aggression, but few studies have addressed the contributing neurobiological factors.
To quantify aggression, investigate function of the amygdala and prefrontal cortex, and assess relationships between brain function and behavior in methamphetamine-dependent individuals.
In a case-control study, aggression and brain activation were compared between methamphetamine-dependent and control participants.
Participants were recruited from the general community to an academic research center.
Thirty-nine methamphetamine-dependent volunteers (16 women) who were abstinent for 7 to 10 days and 37 drug-free control volunteers (18 women) participated in the study; subsets completed self-report and behavioral measures. Functional magnetic resonance imaging (fMRI) was performed on 25 methamphetamine-dependent and 23 control participants.
Main outcome measures
We measured self-reported and perpetrated aggression, and self-reported alexithymia. Brain activation was assessed using fMRI during visual processing of facial affect (affect matching), and symbolic processing (affect labeling), the latter representing an incidental form of emotion regulation.
Methamphetamine-dependent participants self-reported more aggression and alexithymia than control participants and escalated perpetrated aggression more following provocation. Alexithymia scores correlated with measures of aggression. During affect matching, fMRI showed no differences between groups in amygdala activation, but found lower activation in methamphetamine-dependent than control participants in bilateral ventral inferior frontal gyrus. During affect labeling, participants recruited dorsal inferior frontal gyrus and exhibited decreased amygdala activity, consistent with successful emotion regulation; there was no group difference in this effect. The magnitude of decrease in amygdala activity during affect labeling correlated inversely with self-reported aggression in control participants, and perpetrated aggression in all participants. Ventral inferior frontal gyrus activation correlated inversely with alexithymia in control participants.
Contrary to the hypotheses, methamphetamine-dependent individuals may successfully regulate emotions through incidental means (affect labeling). Instead, low ventral inferior frontal gyrus activity may contribute to heightened aggression by limiting emotional insight.
Previous neuroimaging research with adults suggests that the medial prefrontal cortex (MPFC) and the medial posterior parietal cortex (MPPC) are engaged during self-knowledge retrieval processes. However, this has yet to be assessed in a developmental sample. Twelve children and 12 adults (average age = 10.2 and 26.1 years, respectively) reported whether short phrases described themselves or a highly familiar other (Harry Potter) while undergoing functional magnetic resonance imaging. In both children and adults, the MPFC was relatively more active during self- than social knowledge retrieval, and the MPPC was relatively more active during social than self-knowledge retrieval. Direct comparisons between children and adults indicated that children activated the MPFC during self-knowledge retrieval to a much greater extent than adults. The particular regions of the MPPC involved varied between the two groups, with the posterior precuneus engaged by adults, but the anterior precuneus and posterior cingulate engaged by children. Only children activated the MPFC significantly above baseline during self-knowledge retrieval. Implications for social cognitive development and the processing functions performed by the MPFC are discussed.
Goal attainment relies in part on one’s ability to maintain a cognitive representation of the desired goal (goal maintenance), monitor the current state vis-à-vis the targeted end state and remain vigilant for lapses in progress (performance monitoring), and inhibit counter-goal behaviors (response inhibition). Because neurocognitive studies have typically examined these three processes in isolation from one another, little is known regarding if and how they interact during goal pursuit. However, these processes frequently co-occur during online, real-world goal pursuit. The present study employed a novel task to investigate how goal maintenance, performance monitoring, and response inhibition interact with one another. We identified functional activations distinct to each of the processes that correspond to results of prior investigations. In addition, we report interactive effects between response inhibition and goal maintenance in the dorsal anterior cingulate cortex and between performance monitoring and goal maintenance in the superior frontal gyrus and supramarginal gyrus. Implications for studying the neural systems of in situ goals include the need for both experimental designs that distinguish between process, but also more complex, realistic tasks to begin to map interactions among these neurocognitive processes and how they are altered by the presence or absence of one another.
Prosocial decisions can be difficult because they often involve personal sacrifices that do not generate any direct, immediate benefits to the self. The current study used functional magnetic resonance imaging (fMRI) to understand how individuals decide to provide support to others. Twenty-five participants were scanned as they completed a task in which they made costly decisions to contribute money to their family and noncostly decisions to accept personal monetary rewards. Decisions to contribute to the family recruited brain regions involved in self-control and mentalizing, especially for individuals with stronger family obligation preferences. Psychophysiological interaction (PPI) analyses revealed that individuals with stronger family obligation preferences showed greater functional coupling between regions involved in self-control and mentalizing with the ventral striatum, a region involved in reward processing. These findings suggest that prosocial behavior may require both social cognition and deliberate effort, and the application of these processes may result in greater positive reinforcement during prosocial behavior.
Kievit et al.’s target paper exemplifies a trend in recent years in psychology and neuroscience to focus on internal mental and neural processes without integrating actual behavior. We discuss the theoretical status of behavior in the context of their model, and present an extension of the model that explicitly includes behavior. Several theoretical and methodological issues relevant to integrating behavior into the model are considered, particularly the distinction between behavior as measured in the laboratory along with neural and psychological processes (proximal behavior) and behavior as measured in situ as part of ongoing daily experience (distal behavior). We conclude by describing several studies that integrate neural, psychological, and behavioral indicators and discuss how these kinds of studies can facilitate a better understanding of behavior and contribute to theory development.
The human reward system is sensitive to both social (e.g., validation) and non-social rewards (e.g., money) and is likely integral for relationship development and reputation building. However, data is sparse on the question of whether implicit social reward processing meaningfully contributes to explicit social representations such as trust and attachment security in pre-existing relationships. This event-related fMRI experiment examined reward system prediction-error activity in response to a potent social reward—social validation—and this activity's relation to both attachment security and trust in the context of real romantic relationships. During the experiment, participants' expectations for their romantic partners' positive regard of them were confirmed (validated) or violated, in either positive or negative directions. Primary analyses were conducted using predefined regions of interest, the locations of which were taken from previously published research. Results indicate that activity for mid-brain and striatal reward system regions of interest was modulated by social reward expectation violation in ways consistent with prior research on reward prediction-error. Additionally, activity in the striatum during viewing of disconfirmatory information was associated with both increases in post-scan reports of attachment anxiety and decreases in post-scan trust, a finding that follows directly from representational models of attachment and trust.
reward system; prediction-error; social reward; attachment; love; striatum; trust; fMRI
What happens in the mind of a person who first hears a potentially exciting idea?We examined the neural precursors of spreading ideas with enthusiasm, and dissected enthusiasm into component processes that can be identified through automated linguistic analysis, gestalt human ratings of combined linguistic and non-verbal cues, and points of convergence/divergence between the two. We combined tools from natural language processing (NLP) with data gathered using fMRI to link the neurocognitive mechanisms that are set in motion during initial exposure to ideas and subsequent behaviors of these message communicators outside of the scanner. Participants' neural activity was recorded as they reviewed ideas for potential television show pilots. Participants' language from video-taped interviews collected post-scan was transcribed and given to an automated linguistic sentiment analysis (SA) classifier, which returned ratings for evaluative language (evaluative vs. descriptive) and valence (positive vs. negative). Separately, human coders rated the enthusiasm with which participants transmitted each idea. More positive sentiment ratings by the automated classifier were associated with activation in neural regions including medial prefrontal cortex; MPFC, precuneus/posterior cingulate cortex; PC/PCC, and medial temporal lobe; MTL. More evaluative, positive, descriptions were associated exclusively with neural activity in temporal-parietal junction (TPJ). Finally, human ratings indicative of more enthusiastic sentiment were associated with activation across these regions (MPFC, PC/PCC, DMPFC, TPJ, and MTL) as well as in ventral striatum (VS), inferior parietal lobule and premotor cortex. Taken together, these data demonstrate novel links between neural activity during initial idea encoding and the enthusiasm with which the ideas are subsequently delivered. This research lays the groundwork to use machine learning and neuroimaging data to study word of mouth communication and the spread of ideas in both traditional and new media environments.
fMRI; sentiment analysis; natural language processing; information diffusion; word-of-mouth
Classic theories of self-development suggest people define themselves in part through internalized perceptions of other people’s beliefs about them, known as reflected self-appraisals. This study uses functional magnetic resonance imaging to compare the neural correlates of direct and reflected self-appraisals in adolescence (N = 12, ages 11–14 years) and adulthood (N = 12, ages 23–30 years). During direct self-reflection, adolescents demonstrated greater activity than adults in networks relevant to self-perception (medial prefrontal and parietal cortices) and social-cognition (dorsomedial prefrontal cortex, temporal–parietal junction, and posterior superior temporal sulcus), suggesting adolescent self-construals may rely more heavily on others’ perspectives about the self. Activity in the medial fronto-parietal network was also enhanced when adolescents took the perspective of someone more relevant to a given domain.
Although multiple neuroimaging studies suggest that affect labeling (i.e., putting feelings into words) can dampen affect-related responses in the amygdala, the consequences of affect labeling have not been examined in other channels of emotional responding. We conducted four studies examining the effect of affect labeling on self-reported emotional experience. In study one, self-reported distress was lower during affect labeling, compared to passive watching, of negative emotional pictures. Studies two and three added reappraisal and distraction conditions, respectively. Affect labeling showed similar effects on self-reported distress as both of these intentional emotion regulation strategies. In each of the first three studies, however, participant predictions about the effects of affect labeling suggest that unlike reappraisal and distraction, people do not believe affect labeling to be an effective emotion regulation strategy. Even after having the experience of affect labels leading to lower distress, participants still predicted that affect labeling would increase distress in the future. Thus, affect labeling is best described as an incidental emotion regulation process. Finally, study four employed positive emotional pictures and here, affect labeling was associated with diminished self-reported pleasure, relative to passive watching. This suggests that affect labeling tends to dampen affective responses in general, rather than specifically alleviating negative affect.
emotion; emotion regulation; emotional experience
Recent evidence suggests that putting feelings into words activates the prefrontal cortex (PFC), and suppresses the response of the amygdala, potentially helping to alleviate emotional distress. To further elucidate the relationship between brain structure and function in these regions, structural and functional magnetic resonance imaging (MRI) data were collected from a sample of 20 healthy human subjects. Structural MRI data were processed using cortical pattern matching algorithms to produce spatially normalized maps of cortical thickness. During functional scanning, subjects cognitively assessed an emotional target face by choosing one of two linguistic labels (label emotion condition) or matched geometric forms (control condition). Manually prescribed regions of interest for the left amygdala were used to extract percent signal change in this region occurring during the contrast of “label emotion” versus “match forms.” A correlation analysis between left amygdala activation and cortical thickness was then performed along each point of the cortical surface, resulting in a color coded r value at each cortical point. Correlation analyses revealed that gray matter thickness in left ventromedial PFC was inversely correlated with task-related activation in the amygdala. These data add support to a general role of the ventromedial PFC in regulating activity of the amygdala.
emotion; cortical thickness; prefrontal cortex; amygdala; fMRI; MRI
Genes and culture are often thought of as opposite ends of the nature–nurture spectrum, but here we examine possible interactions. Genetic association studies suggest that variation within the genes of central neurotransmitter systems, particularly the serotonin (5-HTTLPR, MAOA-uVNTR) and opioid (OPRM1 A118G), are associated with individual differences in social sensitivity, which reflects the degree of emotional responsivity to social events and experiences. Here, we review recent work that has demonstrated a robust cross-national correlation between the relative frequency of variants in these genes and the relative degree of individualism–collectivism in each population, suggesting that collectivism may have developed and persisted in populations with a high proportion of putative social sensitivity alleles because it was more compatible with such groups. Consistent with this notion, there was a correlation between the relative proportion of these alleles and lifetime prevalence of major depression across nations. The relationship between allele frequency and depression was partially mediated by individualism–collectivism, suggesting that reduced levels of depression in populations with a high proportion of social sensitivity alleles is due to greater collectivism. These results indicate that genetic variation may interact with ecological and social factors to influence psychocultural differences.
5-HTTLPR; serotonin transporter; polymorphism; MAOA-uVNTR; A118G
Family assistance is an important aspect of family relationships for adolescents across many cultures and contexts. Motivations to help family members may be driven by both cultural factors and early family experiences. Here, we used functional magnetic resonance imaging to examine (1) cultural differences in neural reward activity among White and Latino youth during online experiences of family assistance and (2) how prior family experiences related to neural reward activity when helping the family. Participants were scanned as they made decisions to contribute money to their family and themselves. Latino and White participants showed similar behavioral levels of helping but distinct patterns of neural activity within the mesolimbic reward system. Whereas Latino participants showed more reward activity when contributing to their family, White participants showed more reward activity when gaining cash for themselves. In addition, participants who felt more identified with their family and who derived greater fulfillment from helping their family two years prior to the scan showed increased reward system activation when contributing to their family. These results suggest that family assistance may be guided, in part, by the personal rewards one attains from that assistance, and that this sense of reward may be modulated by cultural influences and prior family experiences.
Family assistance; Culture; fMRI; Reward; Social identity
Successful goal pursuit involves repeatedly engaging self-control against temptations or distractions that arise along the way. Laboratory studies have identified the brain systems recruited during isolated instances of self-control, and ecological studies have linked self-control capacity to goal outcomes. However, no study has identified the neural systems of everyday self-control during long-term goal pursuit. The present study integrated neuroimaging and experience-sampling methods to investigate the brain systems of successful self-control among smokers attempting to quit. A sample of 27 cigarette smokers completed a go/no-go task during functional magnetic resonance imaging before they attempted to quit smoking and then reported everyday self-control using experience sampling eight times daily for 3 weeks while they attempted to quit. Increased activation in right inferior frontal gyrus, pre-supplementary motor area, and basal ganglia regions of interest during response inhibition at baseline was associated with an attenuated association between cravings and subsequent smoking. These findings support the ecological validity of neurocognitive tasks as indices of everyday response inhibition.
self-control; smoking cessation; brain-as-predictor; right inferior frontal gyrus; response inhibition; text messaging