The neural substrates of procrastination: A voxel-based morphometry study

Procrastination, depressive symptomatology, and loneliness in later life

OBJECTIVES

Procrastination is an almost universal behaviour and yet little research to date has focused on procrastination among older adults. The purpose of this study was to explore the potential association between age and procrastination, and the potential mediating roles of depressive symptomatology and loneliness.

METHOD

Structural equation modelling was applied to data from 1309 participants (aged 29-92) from two waves United States Health and Retirement Study (2016-2020). Within the model, sex, education, marital status, and job status were added as covariates.

RESULTS

There was no statistically significant direct effect between age and procrastination (β = 0.06, p = 0.106). However, an indirect effect was present via depressive symptomatology (β = -0.40, p < 0.001). No mediating effect of loneliness was observed (β = - 0.01, p = 0.371). Subsequent analysis revealed that the symptoms, fatigue, loneliness, and lack of motivation significantly predicted procrastination.

CONCLUSION

While age was not directly associated with procrastination, increasing age was associated with a decreased likelihood of depressive symptomatology, which was in turn associated with an increased likelihood of procrastination. Such findings indicates that age demonstrates no association with procrastination because of the suppressing effect of depressive symptomatology.

Neural basis responsible for effect of grit on procrastination: The interaction between the self-regulation and motivation neural pathways

Procrastination has a detrimental impact on academic performance, health, and subjective well-being. Previous studies indicated that grit was negatively related to procrastination. However, the underlying neural basis of this relationship remains unclear. To address this issue, we utilized voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) analysis to identify the neural substrates of how is grit linked to procrastination. Behavioral results showed that procrastination was negatively associated with grit. VBM analysis revealed that gray matter volume (GMV) in the left precuneus was positively associated with the consistency of interest (CI), a subcomponent of grit, while the right medial orbital frontal cortex (mOFC) was positively correlated with the perseverance of effort (PE), another subcomponent of grit. Moreover, the RSFC analysis indicated that both precuneus-medial superior frontal gyrus (mSFG) and precuneus-insula connectivity were positively related to CI, while the functional coupling of right mOFC with left anterior cingulate cortex (ACC) was positively related to PE. Importantly, the structural equation modeling (SEM) results were well suited for the influence of grit on procrastination via both self-regulation (mOFC-ACC) and motivation pathways (precuneus-mSFG, precuneus-insula). Together, these findings imply that self-regulation and motivation could be two neural circuits underlying the impact of grit on procrastination.

The vmPFC-IPL functional connectivity as the neural basis of future self-continuity impacted procrastination: the mediating role of anticipated positive outcomes

Procrastination is universally acknowledged as a problematic behavior with wide-ranging consequences impacting various facets of individuals' lives, including academic achievement, social accomplishments, and mental health. Although previous research has indicated that future self-continuity is robustly negatively correlated with procrastination, it remains unknown about the neural mechanisms underlying the impact of future self-continuity on procrastination. To address this issue, we employed a free construction approach to collect individuals' episodic future thinking (EFT) thoughts regarding specific procrastination tasks. Next, we conducted voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) analysis to explore the neural substrates underlying future self-continuity. Behavior results revealed that future self-continuity was significantly negatively correlated with procrastination, and positively correlated with anticipated positive outcome. The VBM analysis showed a positive association between future self-continuity and gray matter volumes in the right ventromedial prefrontal cortex (vmPFC). Furthermore, the RSFC results indicated that the functional connectivity between the right vmPFC and the left inferior parietal lobule (IPL) was positively correlated with future self-continuity. More importantly, the mediation analysis demonstrated that anticipated positive outcome can completely mediate the relationship between the vmPFC-IPL functional connectivity and procrastination. These findings suggested that vmPFC-IPL functional connectivity might prompt anticipated positive outcome about the task and thereby reduce procrastination, which provides a new perspective to understand the relationship between future self-continuity and procrastination.

Self-esteem mediates the relationship between the parahippocampal gyrus and decisional procrastination at resting state

When faced with a conflict or dilemma, we tend to postpone or even avoid making a decision. This phenomenon is known as decisional procrastination. Here, we investigated the neural correlates of this phenomenon, in particular the parahippocampal gyrus (PHG) that has previously been identified in procrastination studies. In this study, we applied an individual difference approach to evaluate participants' spontaneous neural activity in the PHG and their decisional procrastination levels, assessed outside the fMRI scanner. We discovered that the fractional amplitude of low-frequency fluctuations (fALFF) in the caudal PHG (cPHG) could predict participants' level of decisional procrastination, as measured by the avoidant decision-making style. Importantly, participants' self-esteem mediated the relationship between the cPHG and decisional procrastination, suggesting that individuals with higher levels of spontaneous activity in the cPHG are likely to have higher levels of self-esteem and thus be more likely to make decisions on time. In short, our study broadens the PHG's known role in procrastination by demonstrating its link with decisional procrastination and the mediating influence of self-esteem, underscoring the need for further exploration of this mediation mechanism.

The triple psychological and neural bases underlying procrastination: Evidence based on a two-year longitudinal study

The triple brain anatomical network model of procrastination theorized procrastination as the result of psychological and neural dysfunction implicated in self-control, emotion regulation and episodic prospection. However, no studies have provided empirical evidence for such model. To address this issue, we designed a two-wave longitudinal study where participants underwent the resting-state scanning and completed the questionnaires at two time-points that spanned 2-year apart (T1, n = 457; T2, n = 457). Using the cross-lagged panel network modeling (CLPN), we found that triple psychological components at T1, including self-control, emotion regulation (i.e., reappraisal) and episodic prospection, negatively predicted procrastination at T2 in the temporal network. Moreover, the CLPN modeling found that functional connectivity between networks accounting for episodic prospection (EP) and emotion regulation (ER) positively predicted future procrastination in the temporal network. The centrality analyzes further showed that procrastination was greatly affected by other nodes, whilst the psychological component (i.e., episodic prospection), and the functional network connectivity (FNC) of EP- ER exerted strongest impacts on other nodes in the networks, which indicated that treatments targeting episodic prospection might largely help reduce procrastination. Collectively, these findings firstly provide evidence for testifying the triple brain anatomical network model of procrastination, and highlights the contribution of triple psychological and neural components implicated in self-control, emotion regulation and episodic prospection to procrastination that enhances our understanding of causes of procrastination.

The para-hippocampal-medial frontal gyrus functional connectivity mediates the relationship between dispositional optimism and procrastination

Procrastination is a prevalent phenomenon throughout the world, which can lead to worse consequences across life domains, such as academic performance, mental health, and even public policy. Despite the evidence for the association between dispositional optimism and procrastination, the neural mechanisms underlying this link remain unexplored. To address this issue, we employed voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods to explore the underlying links between dispositional optimism and procrastination in a large sample (N=408). The self-report results showed that dispositional optimism was negatively associated with procrastination (r= -.30, p<.001). The VBM analysis indicated that dispositional optimism was positively correlated with gray matter volumes (GMV) in the right para-hippocampal (rPHC), and negatively correlated with GMV in the left cerebellum. Moreover, the functional connectivity analysis with the rPHC as a seed region revealed that rPHC-rMFC (right medial frontal gyrus) functional connectivity was negatively associated with dispositional optimism. Furthermore, the mediation analysis showed that the rPHC-rMFC connectivity partially mediated the relationship between dispositional optimism and procrastination. These results suggested that the rPHC-rMFC connectivity engaged in less task aversiveness by episodic prospection may underlie the association between dispositional optimism and procrastination, which provides a new perspective to understand the relationship between dispositional optimism and procrastination. DATA AVAILABILITY STATEMENT: The data that support the findings of this study are available from the corresponding author upon reasonable request.

Individualized prediction of trait self-control from whole-brain functional connectivity

Self-control is a core psychological construct for human beings and it plays a crucial role in the adaptation to society and achievement of success and happiness for individuals. Although progress has been made in behavioral studies examining self-control, its neural mechanisms remain unclear. In this study, we employed a machine-learning approach-relevance vector regression (RVR) to explore the potential predictive power of intrinsic functional connections to trait self-control in a large sample (N = 390). We used resting-state functional MRI (fMRI) to explore whole-brain functional connectivity patterns characteristic of 390 healthy adults and to confirm the effectiveness of RVR in predicting individual trait self-control scores. A set of connections across multiple neural networks that significantly predicted individual differences were identified, including the classic control network (e.g., fronto-parietal network (FPN), salience network (SAL)), the sensorimotor network (Mot), and the medial frontal network (MF). Key nodes that contributed to the predictive model included the dorsolateral prefrontal cortex (dlPFC), middle frontal gyrus (MFG), anterior cingulate and paracingulate gyri, inferior temporal gyrus (ITG) that have been associated with trait self-control. Our findings further assert that self-control is a multidimensional construct rooted in the interactions between multiple neural networks.

The functional connectivity between left insula and left medial superior frontal gyrus underlying the relationship between rumination and procrastination

Procrastination is regarded as a prevalent problematic behavior that impairs people's physical and mental health. Although previous studies have indicated that trait rumination is robustly positively correlated with procrastination, it remains unknown about the neural substrates underlying the relationship between trait rumination and procrastination. To address this issue, we used voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) approaches to explore the neural basis of the relationship between trait rumination and procrastination. Our behavior results found that trait rumination was significantly positively correlated to procrastination, while the VBM analysis showed that trait rumination was negatively correlated with gray matter volume of the insula. Furthermore, the RSFC results revealed a negative association of the left insula-lmSFG (left medial superior frontal gyrus) functional connectivity with trait rumination. More importantly, the mediation analysis showed that trait rumination could completely mediate the relationship between left insula-lmSFG functional connectivity and procrastination. These results suggest that the left insula-lmSFG functional connectivity involved in emotion regulation modulates the association between trait rumination and procrastination, which provides neural evidence for the relationship between trait rumination and procrastination.

Relationship between Helicopter Parenting and Chinese Elementary School Child Procrastination: A Mediated Moderation Model

BACKGROUND

The family environment is essential for elementary school children's development. With smartphone penetration into all aspects of people's lives, how parenting affects children's behavior may show new patterns.

OBJECTIVE

This study constructed a mediated moderation model, focusing on the mediating role of child self-control and parental phubbing to clarify the relationship between helicopter parenting (over-parenting) and child procrastination and its mechanisms.

METHODS

The Smartphone Addiction Scale for Chinese Adults, Brief Self-Control Scale, Over-Parenting Questionnaire, and Short General Procrastination Scale were employed to investigate 562 elementary school-age children and their parents.

RESULTS

After data analysis, this study showed the following: (1) helicopter parenting was significantly and positively related to child self-control, child procrastination, and parental smartphone use; (2) child self-control partially mediated the relationship between helicopter parenting and child procrastination; and (3) pathways between helicopter parenting and child self-control were moderated by mother-phubbing behavior.

CONCLUSION

These findings inform parents of their roles in family education.

Hybrid brain model accurately predict human procrastination behavior

Procrastination behavior is quite ubiquitous, and should warrant cautions to us owing to its significant influences in poor mental health, low subjective well-beings and bad academic performance. However, how to identify this behavioral problem have not yet to be fully elucidated. 1132 participants were recruited as distribution of benchmark. 81 high trait procrastinators (HP) and matched low trait procrastinators (LP) were screened. To address this issue, we have built upon the hybrid brain model by using hierarchical machine learning techniques to classify HP and LP with multi-modalities neuroimaging data (i.e., grey matter volume, fractional anisotropy, static/dynamic amplitude of low frequency fluctuation and static/dynamic degree centrality). Further, we capitalized on the multiple Canonical Correlation Analysis (mCCA) and joint Independent Component Analysis algorithm (mCCA + jICA) to clarify its fusion neural components as well. The hybrid brain model showed high accuracy to discriminate HP and LP (accuracy rate = 87.04%, sensitivity rate = 86.42%, specificity rate = 85.19%). Moreover, results of mCCA + jICA model revealed several joint-discriminative neural independent components (ICs) of this classification, showing wider co-variants of frontoparietal cortex and hippocampus networks. In addition, this study demonstrated three modal-specific discriminative ICs for classification, highlighting the temporal variants of brain local and global natures in ventromedial prefrontal cortex (vmPFC) and PHC in HP. To sum-up, this research developed a hybrid brain model to identify trait procrastination with high accuracy, and further revealed the neural hallmarks of this trait by integrating neuroimaging fusion data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11571-021-09765-z.

A neuro-computational account of procrastination behavior

Humans procrastinate despite being aware of potential adverse consequences. Yet, the neuro-computational mechanisms underlying procrastination remain poorly understood. Here, we use fMRI during intertemporal choice to inform a computational model that predicts procrastination behavior in independent tests. Procrastination is assessed in the laboratory as the preference for performing an effortful task on the next day as opposed to immediately, and at home as the delay taken in returning completed administrative forms. These procrastination behaviors are respectively modeled as unitary and repeated decisions to postpone a task until the next time step, based on a net expected value that integrates reward and effort attributes, both discounted with delay. The key feature that is associated with procrastination behavior across individuals (both in-lab and at-home) is the extent to which the expected effort cost (signaled by the dorsomedial prefrontal cortex) is attenuated by the delay before task completion. Thus, procrastination might stem from a cognitive bias that would make doing a task later (compared to now) appear as much less effortful but not much less rewarding.

Most humans procrastinate to some extent, despite adverse consequences. Here, the authors show that how much an individual procrastinates, both in the lab and at home, relates to brain signals that reflect temporal discounting of effort cost.

Frontostriatal Functional Connectivity Underlies the Association between Punishment Sensitivity and Procrastination

Procrastination is defined as putting off an intended course of action voluntarily despite the harmful consequences. Previous studies have suggested that procrastination is associated with punishment sensitivity in that high punishment sensitivity results in increased negative utility for task performance. We hypothesized the effects of punishment sensitivity on procrastination would be mediated by a network connecting the caudate nucleus and prefrontal cortex, both of which have been previously associated with self-control and emotional control during procrastination. We employed voxel-based morphometry (VBM) and resting-state functional connectivity (rsFC) to examine the neural substrates of punishment sensitivity and its relationship with procrastination (N = 268). The behavioral results indicated a strong positive correlation between measures of punishment sensitivity and procrastination. The VBM analysis revealed that the gray matter (GM) volume of the right caudate was significantly positively correlated with punishment sensitivity. The primary rsFC analysis revealed connectivity between this caudate location and the bilateral middle frontal gyrus (MFG) was significantly negatively correlated with punishment sensitivity. A mediation model indicated punishment sensitivity completely mediated the relation between functional connectivity within a caudate–bilateral MFG network and procrastination. Our results support the theory that those with higher punishment sensitivity have weaker effective emotional self-control supported by the caudate–MFG network, resulting in greater procrastination.

Neural connectome features of procrastination: Current progress and future direction

Procrastination refers to an irrationally delay for intended courses of action despite of anticipating a negative consequence due to this delay. Previous studies tried to reveal the neural substrates of procrastination in terms of connectome-based biomarkers. Based on this, we proposed a unified triple brain network model for procrastination and pinpointed out what challenges we are facing in understanding neural mechanism of procrastination. Specifically, based on neuroanatomical features, the unified triple brain network model proposed that connectome-based underpinning of procrastination could be ascribed to the abnormalities of self-control network (i.e., dorsolateral prefrontal cortex, DLPFC), emotion-regulation network (i.e., orbital frontal cortex, OFC), and episodic prospection network (i.e., para-hippocampus cortex, PHC). Moreover, based on the brain functional features, procrastination had been attributed to disruptive neural circuits on FPN (frontoparietal network)-SCN (subcortical network) and FPN-SAN (salience network), which led us to hypothesize the crucial roles of interplay between these networks on procrastination in unified triple brain network model. Despite of these findings, poor interpretability and computational model limited further understanding for procrastination from theoretical and neural perspectives. On balance, the current study provided an overview to show current progress on the connectome-based biomarkers for procrastination, and proposed the integrative neurocognitive model of procrastination.

Neural basis underlying the association between expressive suppression and procrastination: The mediation role of the dorsolateral prefrontal cortex

Procrastination can lead to a variety of negative consequences, including poorer health conditions and more financial issues. Previous researches highlight that procrastination is a result of the failure of emotion-regulation. Although substantial studies have shown that emotion regulation plays an essential role in procrastination, little is known about the neural basis of the relationship between expressive suppression and procrastination. To address this question, we employed the voxel-based morphometry (VBM) method to investigate the neural basis underlying how expressive suppression links to procrastination across two independent samples (sample1, N = 98). Expressive suppression was significantly negatively associated with procrastination. Furthermore, VBM results indicated that expressive suppression was positively correlated with gray matter (GM) volumes of the right dorsolateral prefrontal cortex (dlPFC). More importantly, the GM volumes in dlPFC mediated the relationship between expressive suppression and procrastination, which was further replicated in an independent sample (sample 2, N = 110). These findings suggest that dlPFC, which plays a crucial role in inhibitory control, may be the key brain region mediating the relation between expressive suppression and procrastination. The current work provides a new perspective to understand how emotion regulation in terms of expressive suppression plays a role in procrastination.

Neural basis underlying the relation between boredom proneness and procrastination: The role of functional coupling between precuneus/cuneus and posterior cingulate cortex

Procrastination refers to voluntarily delaying an important task despite the fact that this decision will take a heavy toll on daily life. Previous researches have shown that boredom proneness is a robust predictor of procrastination and the default mode network (DMN) could be the neural substrate for the connection between the two variables mentioned above. However, how boredom proneness links to procrastination at the neural level remains unclear. To address this question, we adopted the voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods to identify the neural basis of the relation between boredom proneness and procrastination. Behavioral results indicated that boredom proneness was significantly positively correlated with procrastination. VBM results revealed that boredom proneness was negatively correlated with grey matter volumes in the precuneus/cuneus. Furthermore, the RSFC analyses showed that the functional connectivity between precuneus/cuneus and posterior cingulate cortex (PCC) was positively correlated with boredom proneness. More importantly, a mediation analysis found that boredom proneness played a fully mediating role in improving the relationship between precuneus/cuneus-PCC functional connectivity and procrastination. These findings suggest that the brain functional connectivity engages in attention control may account for the association between boredom proneness and procrastination, and highlight the important role of sustaining concentration on mitigating procrastination.

Outcome Value and Task Aversiveness Impact Task Procrastination through Separate Neural Pathways

The temporal decision model of procrastination has proposed that outcome value and task aversiveness are two separate aspects accounting for procrastination. If true, the human brain is likely to implicate separate neural pathways to mediate the effect of outcome value and task aversiveness on procrastination. Outcome value is plausibly constructed via a hippocampus-based pathway because of the hippocampus's unique role in episodic prospection. In contrast, task aversiveness might be represented through an amygdala-involved pathway. In the current study, participants underwent fMRI scanning when viewing both tasks and future outcomes, without any experimental instruction imposed. The results revealed that outcome value increased activations in the caudate, and suppressed procrastination through a hippocampus-caudate pathway. In contrast, task aversiveness increased activations in the anterior insula, and increased procrastination via an amygdala-insula pathway. In sum, this study demonstrates that people can incorporate both outcome value and task aversiveness into task valuation to decide whether to procrastinate or not; and it elucidates the separate neural pathways via which this occurs.

Brain Structure and Subclinical Symptoms: A Dimensional Perspective of Psychopathology in the Depression and Anxiety Spectrum

Human psychopathology is the result of complex and subtle neurobiological alterations. Categorial DSM or ICD diagnoses do not allow a biologically founded and differentiated description of these diverse processes across a spectrum or continuum, emphasising the need for a scientific and clinical paradigm shift towards a dimensional psychiatric nosology. The subclinical part of the spectrum is, however, of special interest for early detection of mental disorders. We review the current evidence of brain structural correlates (grey matter volume, cortical thickness, and gyrification) in non-clinical (psychiatrically healthy) subjects with minor depressive and anxiety symptoms. We identified 16 studies in the depressive spectrum and 20 studies in the anxiety spectrum. These studies show effects associated with subclinical symptoms in the hippocampus, anterior cingulate cortex, and anterior insula similar to major depression and changes in amygdala similar to anxiety disorders. Precuneus and temporal areas as parts of the default mode network were affected specifically in the subclinical studies. We derive several methodical considerations crucial to investigations of brain structural correlates of minor psycho(patho)logical symptoms in healthy participants. And we discuss neurobiological overlaps with findings in patients as well as distinct findings, e.g. in areas involved in the default mode network. These results might lead to more insight into the early pathogenesis of clinical significant depression or anxiety and need to be enhanced by multi-centre and longitudinal studies.

Neural markers of procrastination in white matter microstructures and networks

More than 15% of adults suffer from pathological procrastination, which leads to substantial harm to their mental and psychiatric health. Our previous work demonstrated the role of three neuroanatomical networks as neural substrates of procrastination, but their potential interaction remains unknown. Three large-scale independent samples (total n = 901) were recruited. In sample A, tract-based spatial statistics (TBSS) and connectome-based graph-theoretical analysis was conducted to probe association between topological properties of white matter (WM) network and procrastination. In sample B, the above analysis was reproduced to demonstrate replicability. In sample C, machine learning models were built to predict individual procrastination. TBSS results showed a negative association between procrastination and WM integrity of limbic-prefrontal connection, and a positive relationship between intra-connection within the limbic system and procrastination. Also, both the efficiency and integrity of limbic WM network were found to be linked to procrastination. The above findings were all confirmed to replicate in an independent sample; prediction models demonstrated that these WM features can predict procrastination accurately in sample C. In conclusion, this study moves forward our understanding of procrastination by clarifying the role of interplay of self-control and emotional regulation with it.

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.

An assessment of the autism neuroimaging literature for the prospects of re-executability

Background: The degree of reproducibility of the neuroimaging literature in psychiatric application areas has been called into question and the issues that relate to this reproducibility are extremely complex. Some of these complexities have to do with the underlying biology of the disorders that we study and others arise due to the technology we apply to the analysis of the data we collect. Ultimately, the observations we make get communicated to the rest of the community through publications in the scientific literature. Methods: We sought to perform a 're-executability survey' to evaluate the recent neuroimaging literature with an eye toward seeing if the technical aspects of our publication practices are helping or hindering the overall quest for a more reproducible understanding of brain development and aging. The topic areas examined include availability of the data, the precision of the imaging method description and the reporting of the statistical analytic approach, and the availability of the complete results. We applied the survey to 50 publications in the autism neuroimaging literature that were published between September 16, 2017 to October 1, 2018. Results: The results of the survey indicate that for the literature examined, data that is not already part of a public repository is rarely available, software tools are usually named but versions and operating system are not, it is expected that reasonably skilled analysts could approximately perform the analyses described, and the complete results of the studies are rarely available.  Conclusions: We have identified that there is ample room for improvement in research publication practices. We hope exposing these issues in the retrospective literature can provide guidance and motivation for improving this aspect of our reporting practices in the future.

An assessment of the autism neuroimaging literature for the prospects of re-executability

Background: The degree of reproducibility of the neuroimaging literature in psychiatric application areas has been called into question and the issues that relate to this reproducibility are extremely complex. Some of these complexities have to do with the underlying biology of the disorders that we study and others arise due to the technology we apply to the analysis of the data we collect. Ultimately, the observations we make get communicated to the rest of the community through publications in the scientific literature. Methods: We sought to perform a 're-executability survey' to evaluate the recent neuroimaging literature with an eye toward seeing if our publication practices are helping or hindering the overall quest for a more reproducible understanding of brain development and aging. The topic areas examined include availability of the data, the precision of the imaging method description and the reporting of the statistical analytic approach, and the availability of the complete results. We applied the survey to 50 publications in the autism neuroimaging literature that were published between September 16, 2017 to October 1, 2018. Results: The results of the survey indicate that for the literature examined, data that is not already part of a public repository is rarely available, software tools are usually named but versions and operating system are not, it is expected that reasonably skilled analysts could approximately perform the analyses described, and the complete results of the studies are rarely available.  Conclusions: We have identified that there is ample room for improvement in research publication practices. We hope exposing these issues in the retrospective literature can provide guidance and motivation for improving this aspect of our reporting practices in the future.

The overlapping region in right hippocampus accounting for the link between trait anxiety and procrastination

Procrastination refers as putting off an intended course of action voluntarily despite expecting to be worse off for the delay, ubiquitously causing troubles across life domains. Prior studies revealed the positive correlation between trait anxiety and procrastination. However, little was known about the neural substrates responsible for the relation between trait anxiety and procrastination. To address this issue, the current study explored the neural basis underlying how trait anxiety linked to procrastination using the voxel-based morphometry (VBM) method across two independent samples. In line with previous studies, the behavioral result confirmed that trait anxiety was positively correlated with procrastination (sample 1). The VBM analyses showed that trait anxiety and procrastination shared the common neural underpinnings in the right hippocampus (sample 1). To verify the reliability of results, the overlapping region in the right hippocampus was defined as a region of interest (ROI) to extract the GM volumes of this area in sample 2. Furthermore, the mediation analysis showed that the GM volumes in the overlapping region played a mediating role in the relationship between trait anxiety and procrastination (sample 2). These results suggested the shared anatomical structure in the right hippocampus, a region implicated in episodic prospection, could be responsible for how trait anxiety related to procrastination. Taken together, present findings yielded insights into the role of episodic prospection accounting for the relationship between trait anxiety and procrastination from a neural basis perspective.

Brain Morphological Dynamics of Procrastination: The Crucial Role of the Self-Control, Emotional, and Episodic Prospection Network

Globally, about 17% individuals are suffering from the maladaptive procrastination until now, which impacts individual's financial status, mental health, and even public policy. However, the comprehensive understanding of neuroanatomical understructure of procrastination still remains gap. 688 participants including 3 independent samples were recruited for this study. Brain morphological dynamics referred to the idiosyncrasies of both brain size and brain shape. Multilinear regression analysis was utilized to delineate brain morphological dynamics of procrastination in Sample 1. In the Sample 2, cross-validation was yielded. Finally, prediction models of machine learning were conducted in Sample 3. Procrastination had a significantly positive correlation with the gray matter volume (GMV) in the left insula, anterior cingulate gyrus (ACC), and parahippocampal gyrus (PHC) but was negatively correlated with GMV of dorsolateral prefrontal cortex (dlPFC) and gray matter density of ACC. Furthermore, procrastination was positively correlated to the cortical thickness and cortical complexity of bilateral orbital frontal cortex (OFC). In Sample 2, all the results were cross-validated highly. Predication analysis demonstrated that these brain morphological dynamic can predict procrastination with high accuracy. This study ascertained the brain morphological dynamics involving in self-control, emotion, and episodic prospection brain network for procrastination, which advanced promising aspects of the biomarkers for it.

Attenuated brain activity during error processing and punishment anticipation in procrastination - a monetary Go/No-go fMRI study

Procrastination is a self-regulatory failure in which people voluntarily but irrationally delay important tasks. Trait procrastination is estimated to affect 15-20% of the total population and leads to a significant decrease in performance, satisfaction with achievements, and quality of life. Procrastination is related to impulsivity and reduced executive control, especially in the domain of inhibition. Moreover, procrastinatory tendencies seem to increase with negative affect, suggesting impaired emotion regulation. The aim of this study was to investigate the neuronal mechanisms of inhibition, error processing, and behavioral control under pressure of punishment in procrastinators. Non-student subjects recruited to low (LP) and high procrastination (HP) groups performed an fMRI monetary Go/No-go task. HP showed significantly lower error-related activity in ACC than LP. There was also a significant group by condition interaction in the ACC and right DLPFC suggesting increase of control during the punishment condition in LP but not HP group. These results suggest that procrastinators have impaired error processing mechanisms which may add to the persistence of procrastination through difficulties in correction of faulty behaviors. Procrastination also seems to be related to a decreased ability to intensify self-control in more demanding situations and/or impaired coping in the context of negative situations.

Brain structure and trait impulsivity: A comparative VBM study contrasting neural correlates of traditional and alternative concepts in healthy subjects

Impulsivity as a trait modulates a range of cognitive functions, e.g. planning, decision-making, or response inhibition. Recent behavioural and psychometric findings challenge both the neurobiological models as well as the conceptualisation of psychometric measures of impulsivity. In the present study, we aimed to test the association of brain structure with the Barratt Impulsiveness Scale (BIS-11), a commonly applied self-rating instrument for impulsivity, using both the classical three-factor-model for impulsive behaviour (motor (IM), attentional (IA) and non-planning impulsivity (INP)), as well as the recently proposed alternative model contrasting inability to wait for reward (IWR) as an index of impulsive choice and rapid response style (RRS) as an index of impulsive action. We analysed brain structural data in a community sample of 85 healthy individuals, who completed the BIS-11, using voxel-based morphometry (CAT12: Computational Anatomy Toolbox 12). Regional volumes were correlated with the three traditional BIS-11 subscales, as well as IWR and RRS. BIS-11 total score was positively correlated with right inferior parietal, postcentral, and supramarginal grey matter (p < 0.05, FWE cluster-level corrected). Attentional impulsivity (IA) was also positively correlated with right inferior and superior parietal and supramarginal gyri. Comparison of the other scales did show some divergence, but most correlations did not survive correction for multiple comparisons. Our findings suggest that difference facets of trait impulsivity might be related to different brain areas, and might thus dissociate along distinct but overlapping neural networks. In contrast to lesion or patient studies, these analyses delineate physiological variance, and can thus help to conceptualise network models in the absence of pathology.

To do it now or later: The cognitive mechanisms and neural substrates underlying procrastination

Procrastination, the voluntary and irrational delay of an intended course of action, has troubled individuals and society extensively. Various studies have been conducted to explain why people procrastinate and to explore the neural substrates of procrastination. First, research has identified many contributing factors to procrastination. Specifically, task aversiveness, future incentives, and time delay of these incentives have been confirmed as three prominent task characteristics that affect procrastination. On the other hand, self-control and impulsivity have been identified as two most predictive traits of procrastination. After identifying contributing factors, two important theories proposed to explain procrastination by integrating these factors are reviewed. Specifically, an emotion-regulation perspective regards procrastination as a form of self-regulation failure that reflects giving priority to short-term mood repair over achieving long-term goals. However, temporal motivation theory explains why people's motivation to act increases when time approaches a deadline with time discounting effect. To further specify the cognitive mechanism underlying procrastination, this study proposes a novel theoretical model which clarifies how the motivation to act and the motivation to avoid vary differently when delaying a task, explaining why people decide not to act now but are willing to act in the future. Of note, few recent studies have investigated neural correlates of procrastination. Specifically, it was revealed that individual differences in procrastination are correlated with structural abnormalities and altered spontaneous metabolism in the parahippocampal cortex and the prefrontal cortex, which might contribute to procrastination through episodic future thinking or memory and emotion regulation, respectively. This article is categorized under: Economics > Individual Decision Making Psychology > Theory and Methods Psychology > Emotion and Motivation Psychology > Reasoning and Decision Making.