Neural mechanisms and personality correlates of the sunk cost effect

Ketamine reverses stress-induced hypersensitivity to sunk costs

How mood interacts with information processing in the brain is thought to mediate the maladaptive behaviors observed in depressed individuals. However, the neural mechanisms underlying impairments in emotion-cognition interactions are poorly understood. This includes influencing the balance between how past-sensitive vs. future-looking one is during decision-making. Recent insights from the field of neuroeconomics offer novel approaches to study changes in such valuation processes in a manner that is biologically tractable and readily translatable across species. We recently discovered that rodents are sensitive to "sunk costs" - a feature of higher cognition previously thought to be unique to humans. The sunk costs bias describes the phenomenon in which an individual overvalues and escalates commitment to continuing an ongoing endeavor, even if suboptimal, as a function of irrecoverable past (sunk) losses - information that, according to classic economic theory, should be ignored. In the present study, mice were exposed to chronic social defeat stress paradigm, a well-established animal model used for the study of depression. Mice were then tested on our longitudinal neuroeconomic foraging task, Restaurant Row. We found mice exposed to this severe stressor displayed an increased sensitivity to sunk costs, without altering overall willingness to wait. Mice were then randomly assigned to receive a single intraperitoneal injection of either saline or ketamine (20 mg/kg). We discovered that stress-induced hypersensitivity to sunk costs was renormalized following a single dose of ketamine. Interestingly, in non-defeated mice, ketamine treatment completely abolished sunk cost sensitivity, causing mice to no longer value irrecoverable losses during re-evaluation decisions who instead based choices solely on the future investment required to obtain a goal. These findings suggest that the antidepressant effects of ketamine may be mediated in part through changes in the processing of past-sensitive information during on-going decision-making, reducing its weight as a potential source of cognitive dissonance that could modulate behavior and instead promoting more future-thinking behavior.

Explicit and implicit effects of gaming content on social media on the behavior of young adults

Excessive gameplay can have negative effects on both mental and physical health, especially among young people. Nowadays, social media platforms are bombarding users with gaming-related content daily. Understanding the effect of this content on people's behavior is essential to gain insight into problematic gaming habits. However, this issue is yet to be studied extensively. In this study, we examined how gaming-related content on social media affects young adults explicitly and implicitly. We studied 25 healthy young adults (average age 21.5 ± 2.2) who played online games casually and asked them to report their gaming desire. We also conducted an implicit association test (IAT) to measure their implicit attitudes toward gaming-related content. We also investigated the relationship between these measures and various psychological factors, such as personality traits, self-efficacy, impulsiveness, and cognitive flexibility. The results revealed that participants had a higher explicit gaming desire when exposed to gaming-related cues on social media than neutral cues. They also had a robust positive implicit attitude toward gaming-related content on social media. Explicit gaming desire was positively correlated with neuroticism levels. Furthermore, the IAT effect was negatively correlated with self-efficacy and cognitive flexibility levels. However, there were no significant correlations between explicit gaming desire/IAT effect and impulsiveness levels. These findings suggest that gaming-related content on social media can affect young adults' behavior both explicitly and implicitly, highlighting the need for further research to prevent gaming addiction in vulnerable individuals.

Personality Traits Associated with Treatment Choice with an Explicit Statistical Prediction After an Explanation in a Negative Context: A Study in Patients with Glaucoma

Purpose

Over 50% of patients with early-stage glaucoma discontinue topical therapy within the first 6 months of treatment initiation. This risk of discontinuation could be reduced by how the ophthalmologist explains the treatment plan. Ophthalmologists can explain the treatment plan to patients in either positive or negative contexts. Although explanations in a negative context can be selected depending on the medical situation, identification of patients who will choose the treatment with explicit statistical prediction after an explanation in a negative context is important; personality traits are related to these emotional decisions. Therefore, in the present study, we examined the personality traits associated with choice of treatment with explicit statistical prediction after an explanation in a negative context.

Patients and Methods

A total of 147 patients with glaucoma were recruited for this study. The questionnaire booklets used contained positively framed or negatively framed versions of an "Asian disease problem" to enable examination of the influence of the way in which a problem is framed (framing effect) on the participants' decision-making. The Japanese version of the Ten-Item Personality Inventory was used to estimate the personality traits of the participants.

Results

Low conscientiousness was identified as the only variable that was strongly predictive of the choice of treatment with explicit statistical prediction (β = -0.44, z = 2.19, p = 0.03). In addition, while the association was not statistically significant, low neuroticism was found to be weakly predictive of the choice of uncertain treatment (β = -0.37, z = 1.73, p = 0.08).

Conclusion

In conclusion, we showed that low levels of conscientiousness predict the choice of treatment with explicit statistical prediction (ie, topical treatment) for glaucoma after an explanation in a negative context.

Behavioural Models of Risk-Taking in Human-Robot Tactile Interactions

Touch can have a strong effect on interactions between people, and as such, it is expected to be important to the interactions people have with robots. In an earlier work, we showed that the intensity of tactile interaction with a robot can change how much people are willing to take risks. This study further develops our understanding of the relationship between human risk-taking behaviour, the physiological responses by the user, and the intensity of the tactile interaction with a social robot. We used data collected with physiological sensors during the playing of a risk-taking game (the Balloon Analogue Risk Task, or BART). The results of a mixed-effects model were used as a baseline to predict risk-taking propensity from physiological measures, and these results were further improved through the use of two machine learning techniques-support vector regression (SVR) and multi-input convolutional multihead attention (MCMA)-to achieve low-latency risk-taking behaviour prediction during human-robot tactile interaction. The performance of the models was evaluated based on mean absolute error (MAE), root mean squared error (RMSE), and R squared score (R2), which obtained the optimal result with MCMA yielding an MAE of 3.17, an RMSE of 4.38, and an R2 of 0.93 compared with the baseline of 10.97 MAE, 14.73 RMSE, and 0.30 R2. The results of this study offer new insights into the interplay between physiological data and the intensity of risk-taking behaviour in predicting human risk-taking behaviour during human-robot tactile interactions. This work illustrates that physiological activation and the intensity of tactile interaction play a prominent role in risk processing during human-robot tactile interaction and demonstrates that it is feasible to use human physiological data and behavioural data to predict risk-taking behaviour in human-robot tactile interaction.

Association of cognitive flexibility with neural activation during the theory of mind processing

Theory of mind (ToM), which is the ability to infer and reason about others' mental states, plays a key role in successful social interactions. Previous studies have shown that cognitive flexibility (CF), which refers to the ability to adequately switch between different perspectives, is linked to ToM performance in a variety of experimental tasks. However, the mechanisms of the association between CF and ToM is still largely unknown. Here, we investigated the relation of CF with neural activity during ToM processing in 26 healthy male adults using a functional magnetic resonance imaging task of moving shapes in social patterns. The CF abilities were estimated using the self-report Cognitive Flexibility Scale. Diverse brain areas, including the middle frontal gyrus (MFG), inferior frontal gyrus, amygdala, precuneus, and temporoparietal junction (TPJ), were activated during ToM processing. In these areas, individual differences in CF abilities were associated with the strength of neural activity in the right MFG and TPJ. These findings highlight the notion that cognitive ability to switch between different perspectives according to a changing environment is crucial for the attribution of mental state to others, and suggest that the right MFG and TPJ are deserving of further examination for the development of new therapies to improve social cognition in clinical populations.

High-Definition Transcranial Stimulation over the Dorsolateral Prefrontal Cortex Alters the Sunk Cost Effect: A Mental Accounting Framework

The sunk cost effect refers to the fact that human decisions are consistently influenced by previous irrecoverable and irrelevant costs. Recent neuroimaging experiments suggest that the dorsolateral prefrontal cortex (dlPFC) plays a pivotal role in the sunk cost effect yet the causal and neurocomputational role of the dlPFC remains elusive. In this study, two cohorts of healthy human male and female adults were recruited to complete a novel two-step decision-making task during the anodal-sham or cathodal-sham high-definition transcranial direct current stimulation (HD-tDCS) over the dlPFC, respectively. Consistent with previous studies, we showed that the sunk cost deterred participants from making further investment and therefore engendered a de-escalation effect. Such behavior can be captured by a weighted mental accounting model with a recalibrated reference point in which the direction and magnitude of the sunk cost effects hinge on the decision weights apportioned to the option values. Interestingly, transcranial stimulation did not influence participants' initial willingness to incur sunk costs but only altered sunk costs' downstream effects. Specifically, anodal stimulation over the right dlPFC amplified the de-escalation effect of sunk costs whereas cathodal stimulation yielded the opposite result. HD-tDCS also changed the decision weights of the mental accounting model, providing a causal and computational link between PFC and sunk cost effects.SIGNIFICANCE STATEMENT Traditional economic theory assumes that decisions only concern the marginal costs and benefits yet human choices are notoriously susceptible to previously-incurred costs (termed the sunk cost effect). In the current study, we showed that direct current stimulation (DCS) of the right dorsolateral prefrontal cortex (dlPFC) altered sunk cost effects in participants' subsequent choices. Such effects can be captured by a mental accounting model where transcranial stimulation modulates the decision weights assigned to different options in the value integration process. These findings help elucidate the computational and causal role of the dlPFC in the context of sunk costs.

Decision Flexibilities in Autism Spectrum Disorder: An fMRI Study of Moral Dilemmas

People make flexible decisions across a wide range of contexts to resolve social or moral conflicts. Individuals with autism spectrum disorder (ASD) frequently report difficulties in such behaviors, which hinders the flexibility in changing strategies during daily activities or adjustment of perspective during communication. However, the underlying mechanisms of this issue are insufficiently understood. This study aimed to investigate decision flexibility in ASD using a functional magnetic resonance imaging task that involved recognizing and resolving two types of moral dilemmas: cost–benefit analysis (CBA) and mitigating inevitable misconducts (MIM). The CBA session assessed the participants’ pitting of result-oriented outcomes against distressful harmful actions, whereas the MIM session assessed their pitting of the extenuation of a criminal sentence against a sympathetic situation of defendants suffering from violence or disease. The behavioral outcome in CBA-related flexibility was significantly lower in the ASD group compared to that of the typical development group. In the corresponding CBA contrast, activation in the left inferior frontal gyrus was lower in the ASD group. Meanwhile, in the MIM-related flexibility, there were no significant group differences in behavioral outcome or brain activity. Our findings add to our understanding of flexible decision-making in ASD.

Sunk cost effects hinge on the neural recalibration of reference points in mental accounting

The context of reinforcement history drastically influences human value-based choices. Mental accounting theory concerns how prior outcomes are perceived, combined and assigned into specific "mental" accounts to influence subsequent decisions but remains agnostic about the underlying computational and neural mechanisms. In a two-stage sequential decision-making task, we found previously incurred costs and bonuses biased subjects' choices in the opposite directions with similar magnitudes. Such effects were consistent with a computational model where the reference point was recalibrated by prior gains and losses encoded in the ventral striatum activities. Moreover, individual's susceptibility to prior outcomes was captured by the response of the dorsolateral prefrontal cortex and its functional connectivity with the medial orbitofrontal cortex, whose activity tracked the value of the chosen option. Our findings provide both behavioral and neural evidence of how sunk costs, benefits, and prospects are integrated within the mental accounting framework to influence choice behavior.

Delays to Reward Delivery Enhance the Preference for an Initially Less Desirable Option: Role for the Basolateral Amygdala and Retrosplenial Cortex

Temporal costs influence reward-based decisions. This is commonly studied in temporal discounting tasks that involve choosing between cues signaling an imminent reward option or a delayed reward option. However, it is unclear whether the temporal delay before a reward can alter the value of that option. To address this, we identified the relative preference between different flavored rewards during a free-feeding test using male and female rats. Animals underwent training where either the initial preferred or the initial less preferred reward was delivered noncontingently. By manipulating the intertrial interval during training sessions, we could determine whether temporal delays impact reward preference in a subsequent free-feeding test. Rats maintained their initial preference if the same delays were used across all training sessions. When the initial less preferred option was delivered after short delays (high reward rate) and the initial preferred option was delivered after long delays (low reward rate), rats expectedly increased their preference for the initial less desirable option. However, rats also increased their preference for the initial less desirable option under the opposite training contingencies: delivering the initial less preferred reward after long delays and the initial preferred reward after short delays. These data suggest that sunk temporal costs enhance the preference for a less desirable reward option. Pharmacological and lesion experiments were performed to identify the neural systems responsible for this behavioral phenomenon. Our findings demonstrate the basolateral amygdala and retrosplenial cortex are required for temporal delays to enhance the preference for an initially less desirable reward.SIGNIFICANCE STATEMENT The goal of this study was to determine how temporal delays influence reward preference. We demonstrate that delivering an initially less desirable reward after long delays subsequently increases the consumption and preference for that reward. Furthermore, we identified the basolateral amygdala and the retrosplenial cortex as essential nuclei for mediating the change in reward preference elicited by sunk temporal costs.

Framing and self-responsibility modulate brain activities in decision escalation

Background

Escalation of commitment is a common bias in human decision making. The present study examined (1) differences in neural recruitment for escalation and de-escalation decisions of prior investments, and (2) how the activations of these brain networks are affected by two factors that can arguably modulate escalation decisions: (i) self-responsibility, and (ii) framing of the success probabilities.

Results

Imaging data were obtained from functional magnetic resonance imaging (fMRI) applied to 29 participants. A whole-brain analysis was conducted to compare brain activations between conditions. ROI analysis, then, was used to examine if these significant activations were modulated by two contextual factors. Finally, mediation analysis was applied to explore how the contextual factors affect escalation decisions through brain activations. The findings showed that (1) escalation decisions are faster than de-escalation decisions, (2) the corresponding network of brain regions recruited for escalation (anterior cingulate cortex, insula and precuneus) decisions differs from this recruited for de-escalation decisions (inferior and superior frontal gyri), (3) the switch from escalation to de-escalation is primarily frontal gyri dependent, and (4) activation in the anterior cingulate cortex, insula and precuneus were further increased in escalation decisions, when the outcome probabilities of the follow-up investment were positively framed; and activation in the inferior and superior frontal gyri in de-escalation decisions were increased when the outcome probabilities were negatively framed.

Conclusions

Escalation and de-escalation decisions recruit different brain regions. Framing of possible outcomes as negative leads to escalation decisions through recruitment of the inferior frontal gyrus. Responsibility for decisions affects escalation decisions through recruitment of the superior (inferior) gyrus, when the decision is framed positively (negatively).

The effect of conscientiousness on procrastination: The interaction between the self-control and motivation neural pathways

Procrastination is a prevalent and universal problematic behavior, largely impairing individual's health, wealth and well-being. Substantial studies have confirmed that conscientiousness, one of the big five personality, showed markedly inverse relation with procrastination. However, it is hitherto unknown about the neural basis underlying the impact of conscientiousness on procrastination. To address this issue, we employed the voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods to explore the neural substrates of conscientiousness responsible for procrastination (N = 330). In line with previous findings, the behavioral results showed a strong negative correlation between conscientiousness and procrastination (r = -.75). The VBM analysis found that conscientiousness was positively correlated with gray matter (GM) volumes in the left dorsal-lateral prefrontal cortex (dlPFC), right orbital frontal cortex (OFC) and right putamen, but negatively correlated with that in the left insula. Moreover, the RSFC results revealed that both dlPFC-IPL (inferior parietal lobule) and dlPFC-PCC (posterior cingulate gyrus) functional connectivity were positively associated with conscientiousness, while the functional connectivity of parahippocampal gyrus (PHC)-putamen and insula-IPL were negatively associated with conscientiousness. More importantly, the structural equation modeling (SEM) integrating RSFC results were well fitted for the influence process of conscientiousness on procrastination by both self-control (i.e., dlPFC-IPL, dlPFC-PCC) and motivation pathways (i.e., PHC-putamen, insula-IPL). The current findings suggest that self-control and motivation could be the two neural pathways underlying the impact of conscientiousness on procrastination, which provides a new perspective to understand the relationship between conscientiousness and procrastination.

Impact of past experiences on decision-making in autism spectrum disorder

People are often influenced by past costs in their current decision-making, thus succumbing to a well-known bias recognized as the sunk cost effect. A recent study showed that the sunk cost effect is attenuated in individuals with autism spectrum disorder (ASD). However, the study only addressed one situation of utilization decision by focusing on the choice between similar attractive alternatives with different levels of sunk costs. Thus, it remains unclear how individuals with ASD behave under sunk costs in different types of decision situations, particularly progress decisions, in which the decision-maker allocates additional resources to an initially chosen alternative. The sunk cost effect in progress decisions was estimated using an economic task designed to assess the effect of the past investments on current decision-making. Twenty-four individuals with ASD and 21 age-, sex-, smoking status-, education-, and intelligence quotient-level-matched typical development (TD) subjects were evaluated. The TD participants were more willing to make the second incremental investment if a previous investment was made, indicating that their decisions were influenced by sunk costs. However, unlike the TD group, the rates of investments were not significantly increased after prior investments in the ASD group. The results agree with the previous evidence of a reduced sensitivity to context stimuli in individuals with ASD and help us obtain a broader picture of the impact of sunk costs on their decision-making. Our findings will contribute to a better understanding of ASD and may be useful in addressing practical implications of their socioeconomic behavior.

Sunk Cost Effect in Individuals with Autism Spectrum Disorder

The sunk cost effect, an interesting and well-known decision bias, is pervasive in real life and has been studied in various disciplines. In this study, we modified a task exemplifying the sunk cost effect and used it to evaluate this behavior in individuals with autism spectrum disorder (ASD). The control group exhibited a typical sunk cost effect in our task. We found that the sunk cost effect was lower in the ASD group than in the control group. The results agree with previous evidence of reduced sensitivity to context stimuli in individuals with ASD and extend this finding to the context of the sunk cost effect. Our findings are useful in addressing the practical implications on their socioeconomic behavior.

An fMRI study of decision-making under sunk costs in gambling disorder

The sunk cost effect is the tendency to continue an investment, or take an action, even though it has higher future costs than benefits, if costs of time, money, or effort were previously incurred. This type of decision bias is pervasive in real life and has been studied in various disciplines. Previous studies and clinical observations suggest that decision-making under sunk costs is altered in gambling disorder (GD). However, the neural mechanisms of decision-making under sunk costs in GD remain largely unknown, and so is their association with the clinical characteristics of this patient group. Here, by combining functional magnetic resonance imaging and the task that demonstrated a clear example of the sunk cost effect, we investigated the neural correlates during decision-making under sunk costs in GD. We found no significant differences in the strength of the sunk cost effect between the GD and healthy control (HC) groups. However, the strength of the sunk cost effect in patients with GD showed a significant negative correlation with abstinence period and a marginally significant positive correlation with the duration of illness. We also found a reduction in the neural activation in the dorsal medial prefrontal cortex during decision-making under sunk costs for the GD group compared with the HC group. Furthermore, in patients with GD, the levels of activation in this area negatively correlated with the duration of illness. These findings have important clinical implications. This study will contribute to a better understanding of the mechanisms underlying altered decision-making abilities in GD.