The mediating effect of attentional impulsivity between mindfulness and problematic smartphone use.

OBJECTIVE: Problematic smartphone use has been linked to lower levels of mindfulness, impaired attentional function, and higher impulsivity. This study aimed to identify the psychological mechanisms of problematic smartphone use by exploring the relationship between addictive smartphone use, mindfulness, attentional function and impulsivity. METHODS: Ninety participants were evaluated with the smartphone addiction proneness scale and classified into the problematic smartphone use group (n = 42; 24 women; mean age: 27.6 ± 7.2 years) or normal use group (n = 48; 22 women; mean age: 30.1 ± 5.7 years). All participants completed self-report questionnaires evaluating their trait impulsivity and mindfulness and attention tests that assessed selective, sustained and divided attention. We compared the variables between the groups and explored the relationship between mindfulness, attentional function, impulsivity and addictive smartphone use through mediation analysis. RESULTS: The problematic smartphone use group showed higher trait impulsivity and lower mindfulness than the normal use group. There were no significant group differences in performance on attention tests. Levels of addictive smartphone use were significantly correlated with higher levels of trait impulsivity and lower levels of mindfulness, but not with performance on attention tests. Mediation analysis showed that acting with awareness, an aspect of mindfulness, reduces the degree of addictive smartphone use through attentional impulsivity, one of the trait impulsivity. CONCLUSION: Acting without sufficient awareness could influence addictive smartphone use by mediating attentional impulsivity. This supports that executive control deficits, reflected in high attentional impulsivity, contribute to problematic smartphone use. Our findings imply that mindfulness-based interventions can enhance executive control over smartphone use by promoting awareness.

Multimodal-based machine learning approach to classify features of internet gaming disorder and alcohol use disorder: A sensor-level and source-level resting-state electroencephalography activity and neuropsychological study.

OBJECTIVES: Addictions have recently been classified as substance use disorder (SUD) and behavioral addiction (BA), but the concept of BA is still debatable. Therefore, it is necessary to conduct further neuroscientific research to understand the mechanisms of BA to the same extent as SUD. The present study used machine learning (ML) algorithms to investigate the neuropsychological and neurophysiological aspects of addictions in individuals with internet gaming disorder (IGD) and alcohol use disorder (AUD). METHODS: We developed three models for distinguishing individuals with IGD from those with AUD, individuals with IGD from healthy controls (HCs), and individuals with AUD from HCs using ML algorithms, including L1-norm support vector machine, random forest, and L1-norm logistic regression (LR). Three distinct feature sets were used for model training: a unimodal-electroencephalography (EEG) feature set combined with sensor- and source-level feature; a unimodal-neuropsychological feature (NF) set included sex, age, depression, anxiety, impulsivity, and general cognitive function, and a multimodal (EEG + NF) feature set. RESULTS: The LR model with the multimodal feature set used for the classification of IGD and AUD outperformed the other models (accuracy: 0.712). The important features selected by the model highlighted that the IGD group had differential delta and beta source connectivity between right intrahemispheric regions and distinct sensor-level EEG activities. Among the NFs, sex and age were the important features for good model performance. CONCLUSIONS: Using ML techniques, we demonstrated the neurophysiological and neuropsychological similarities and differences between IGD (a BA) and AUD (a SUD).

Changes in the Circadian Rhythm of High-Frequency Heart Rate Variability Associated With Depression.

BACKGROUND: Heart rate variability (HRV) extracted from electrocardiogram measured for a short period during a resting state is clinically used as a bio-signal reflecting the emotional state. However, as interest in wearable devices increases, greater attention is being paid to HRV extracted from long-term electrocardiogram, which may contain additional clinical information. The purpose of this study was to examine the characteristics of HRV parameters extracted through long-term electrocardiogram and explore the differences between participants with and without depression and anxiety symptoms. METHODS: Long-term electrocardiogram was acquired from 354 adults with no psychiatric history who underwent Holter monitoring. Evening and nighttime HRV and the ratio of nighttime-to-evening HRV were compared between 127 participants with depressive symptoms and 227 participants without depressive symptoms. Comparisons were also made between participants with and without anxiety symptoms. RESULTS: Absolute values of HRV parameters did not differ between groups based on the presence of depressive or anxiety symptoms. Overall, HRV parameters increased at nighttime compared to evening. Participants with depressive symptoms showed a significantly higher nighttime-to-evening ratio of high-frequency HRV than participants without depressive symptoms. The nighttime-to-evening ratio of HRV parameters did not show a significant difference depending on the presence of anxiety symptoms. CONCLUSION: HRV extracted through long-term electrocardiogram showed circadian rhythm. Depression may be associated with changes in the circadian rhythm of parasympathetic tone.

Dorsal striatal functional connectivity changes in Internet gaming disorder: A longitudinal magnetic resonance imaging study.

Internet gaming disorder (IGD) is a behavioral addiction involving excessive online game use despite negative psychosocial consequences. Unrestricted online gaming may lead to changes in striatal activity and the relationship between the striatum and other cortical regions. This study investigated structural and functional abnormalities involving the striatum through longitudinal follow-up magnetic resonance imaging (MRI) assessments. Eighteen young males with IGD (mean age: 23.8 ± 2.0 years) and 18 controls (mean age: 23.9 ± 2.7 years) were evaluated. Subjects were reassessed ≥1 year after the first visit (mean follow-up duration: 22.8 ± 6.7 months), using voxel-based morphometry and seed-based resting-state functional connectivity (FC) analyses in seed regions of the dorsal and ventral striatum. Subjects with IGD had smaller gray matter volume (GMV) in the anterior/middle cingulate cortex compared with controls during initial and follow-up assessments. They exhibited decreased FC between the left dorsal putamen and left medial prefrontal cortex (mPFC) compared with controls. They exhibited increased FC strength between the right dorsal putamen and right middle occipital gyrus (MOG) during follow-up. Subjects with IGD showed a significant correlation between changes in the dorsal putamen-MOG FC and gaming time per day. Young males with IGD showed an altered FC pattern in the dorsal striatum during follow-up. FC of the dorsal striatum in IGD increased in the mPFC and decreased in the MOG. These findings showed that IGD was accompanied by weakening of prefrontal control and strengthening of the sensorimotor network, suggesting that uncontrolled gaming may be related with functional neural changes in the dorsal striatum.

Regional Gray Matter Volume Related to High Occupational Stress in Firefighters.

BACKGROUND: Firefighters inevitably encounter emotionally and physically stressful situations at work. Even firefighters without diagnosed post-traumatic stress disorder receive clinical attention because the nature of the profession exposes them to repetitive trauma and high occupational stress. This study investigated gray matter abnormalities related to high occupational stress in firefighters using voxel-based morphometry (VBM) and surface-based morphometry (SBM). METHODS: We assessed 115 subjects (112 males and 3 females) using magnetic resonance imaging and evaluated occupational stress by the Korean Occupational Stress Scale-26 (KOSS-26). Subjects were classified into highly or lowly stressed groups based on the median value of the KOSS-26. RESULTS: In VBM analysis, we found that firefighters with high occupational stress had lower gray matter volume (GMV) in both sides of the insula, the left amygdala, the right medial prefrontal cortex (mPFC), and the anterior cingulate cortex than firefighters with low occupational stress. In SBM analysis based on regions of interest, the GMV of the bilateral insula and right mPFC were also lower in the highly stressed group. Within the highly stressed group, low GMV of the insula was significantly correlated with the length of service (left: r = -0.347, P = 0.009; right: r = -0.333, P = 0.012). CONCLUSION: Our findings suggest that regional GMV abnormalities are related to occupational stress. Regional gray matter abnormalities and related emotional dysregulation may contribute to firefighter susceptibility to burnout.

Characteristics of Autonomic Activity and Reactivity During Rest and Emotional Processing and Their Clinical Correlations in Somatic Symptom Disorder.

OBJECTIVE: Altered autonomic nervous system activity is considered to be involved in the pathophysiology of somatic symptom disorder (SSD). This study aimed to investigate whether patients with SSD have disturbed autonomic activity during rest and reactivity to emotional processing and whether altered autonomic nervous system correlates with clinical characteristics and interoceptive accuracy in SSD. METHODS: We recruited 23 patients with SSD and 20 healthy controls. Heart rate variability (HRV) was assessed during recording at rest and during performance of an emotional face dot-probe task. Alpha-amylase responses were also assessed. Patients with SSD completed a self-assessment survey and heart beat perception task, which reflects interoceptive awareness. RESULTS: Patients with SSD had lower low-frequency HRV, high-frequency HRV, standard deviation of normal to normal R-R intervals (SDNN), and proportion of successive R-R intervals greater than 50 milliseconds (pNN50) at rest (p < .05). The reactivity scores (during-task activity minus resting activity) for SDNN and pNN50 were significantly different between patients with SSD and controls (SDNN: p = .013; pNN50: p = .008). In addition, resting HRV parameters (low-frequency, high-frequency, SDNN, pNN50) correlated with heart beat perception error (p < .01) in patients with SSD. No significant differences in α-amylase activity were found. CONCLUSIONS: Our findings showed that patients with SSD have altered resting-state autonomic activity and reactivity to emotional processing, and the resting-state autonomic activity correlated with their interoceptive awareness. These findings suggest that disturbed interactions between the autonomic nervous, affective, and interoceptive systems may be involved in the pathophysiology of SSD.

Abnormal gray matter volume and impulsivity in young adults with Internet gaming disorder.

Reduced executive control is one of the central components of model on the development and maintenance of Internet gaming disorder (IGD). Among the various executive control problems, high impulsivity has consistently been associated with IGD. We performed voxel-based morphometric analysis with diffeomorphic anatomical registration by using an exponentiated Lie algebra algorithm (DARTEL) to investigate the relationship of gray matter abnormalities to impulsivity in IGD. Thirty-one young male adults whose excessive Internet gaming began in early adolescence, and 30 age-matched male healthy controls were examined. IGD subjects showed smaller gray matter volume (GMV) in brain regions implicated in executive control, such as the anterior cingulate cortex and the supplementary motor area. The GMVs in the anterior cingulate cortex and the supplementary motor area were negatively correlated with self-reporting scales of impulsiveness. IGD subjects also exhibited smaller GMV in lateral prefrontal and parietal cortices comprising the left ventrolateral prefrontal cortex and the left inferior parietal lobule when compared with healthy controls. The GMVs in the left ventrolateral prefrontal cortex were negatively correlated with lifetime usage of Internet gaming. These findings suggest that gray matter abnormalities in areas related to executive control may contribute to high impulsivity of young adults with IGD. Furthermore, alterations in the prefrontal cortex were related with long-term excessive Internet gaming during adolescence.

Changes in interoceptive accuracy related to emotional interference in somatic symptom disorder.

OBJECTIVE: The somatic symptom disorder (SSD) is characterized by one or more distressing or disabling somatic symptoms accompanied by an excessive amount of time, energy and emotion related to the symptoms. These manifestations of SSD have been linked to alterations in perception and appraisal of bodily signals. We hypothesized that SSD patients would exhibit changes in interoceptive accuracy (IA), particularly when emotional processing is involved. METHODS: Twenty-three patients with SSD and 20 healthy controls were recruited. IA was assessed using the heartbeat perception task. The task was performed in the absence of stimuli as well as in the presence of emotional interference, i.e., photographs of faces with an emotional expression. IA were examined for correlation with measures related to their somatic symptoms, including resting-state heart rate variability (HRV). RESULTS: There was no significant difference in the absolute values of IA between patients with SSD and healthy controls, regardless of the condition. However, the degree of difference in IA without emotional interference and with neutral facial interference was greater in patients with SSD than in healthy controls (p = 0.039). The IA of patients with SSD also showed a significant correlation with low-frequency HRV (p = 0.004) and high-frequency HRV (p = 0.007). CONCLUSION: SSD patients showed more significant changes in IA when neutral facial interference was given. These results suggest that bodily awareness is more affected by emotionally ambiguous stimuli in SSD patients than in healthy controls.

Functional connectivity of the amygdala in relation to high stress and low mindfulness.

BACKGROUND: High psychological stress has been associated with several brain functional changes, including functional connectivity (FC) alterations in regions such as the prefrontal cortex and the amygdala. This study explored FC alterations associated with high perceived stress, and also investigated whether these neuroimaging features were correlated with low levels of mindfulness. METHODS: This study included 29 adults (12 males and 17 females; mean age: 27.6 ±â€¯3.2) who complained of moderate or higher perceived stress and 31 adults (17 males and 14 females; mean age: 29.2 ±â€¯7.2) who complained of low-level stress on the questionnaire scale. Seed-based resting-state FC analysis was conducted to compare between high and low stress groups. The dorsolateral prefrontal cortex (DLPFC), the ventromedial prefrontal cortex (VMPFC) and the amygdala were selected as seeds. RESULTS: High stress group showed weaker left amygdala-based FC in the left cerebellum crus II and the left orbitofrontal cortex compared with low stress group. High stress group had weaker FC between the left DLPFC and the left inferior parietal lobule. On the contrary, high stress group had stronger FC between the left VMPFC and the left caudate compared with low stress group. Weaker FC between the amygdala and the cerebellum crus II was correlated with lower level of awareness facet of mindfulness. CONCLUSIONS: Those with high perceived stress showed low levels of mindfulness and several FC alterations centered on the prefrontal cortex and amygdala. Our findings also suggest that weak amygdala-based FC alterations associated with high psychological stress are related to low-level awareness facet of mindfulness.

Altered functional connectivity of the default mode and dorsal attention network in subjective cognitive decline.

Subjective cognitive decline (SCD) is a clinical condition in which performance on standardized cognitive tests does not indicate impairment like mild cognitive impairment (MCI), but self-experienced cognitive capacity persistently declines. We aimed to explore the functional connectivity (FC) characteristics of SCD subjects compared to healthy controls and MCI patients. Resting-state functional MRI was performed on 152 elderly subjects: 65 normal controls, 62 SCD subjects, and 25 MCI patients. A seed-based FC analysis was performed to compare groups. The major brain regions of the default mode network (DMN) and dorsal attention network (DAN), large-scale brain networks disrupted in patients with dementia, were selected as seed regions. As a result, the SCD group showed stronger FC than the MCI group between DMN seeds and the supramarginal gyrus. Both the SCD and MCI groups showed stronger FC between the left lateral parietal cortex and right dorsolateral prefrontal cortex. In the FC analysis centred on DAN seeds, both the SCD and MCI groups showed weaker FC of the right posterior intraparietal sulcus in the left anterior cingulate cortex and the left insula, compared to those in the control group. Within the SCD group, hyperconnectivity between the right lateral parietal cortex and left supramarginal gyrus was significantly correlated with better performance on the Controlled Oral Word Association Test. In conclusion, the SCD group showed several DMN- and DAN-related FC alterations, similar to the MCI group, but with distinct hyperconnectivity between DMN seeds and the supramarginal gyrus. In particular, SCD has DMN-related FC patterns distinct from those of MCI that are associated with verbal fluency retention.

Mental Health Problems During COVID-19 and Attitudes Toward Digital Therapeutics.

OBJECTIVE: We aimed to elucidate public mental health problems and associated factors during the coronavirus disease-2019 (COVID-19). Furthermore, we evaluated people's attitudes toward digital therapeutics during the pandemic. METHODS: Data was collected online from participants, aged between 20-50 without any history of mental illness, from June 1st to June 30th 2021. The survey consisted of questions regarding demographics, changes during pandemic and attitude towards digital therapeutics, and mental health measures. RESULTS: Among the total of 445 participants, 49.2% reported significant level of stress and 13.5% and 7.0% met the screening criteria for major depressive disorder and generalized anxiety disorder, respectively. Significant predictive factors for mental health problems were-younger age group, female sex, currently being treated for medical or surgical disease, change in the amount of time spent on mobile device or computer after pandemic, change in household income, and change in work environment due to pandemic. Furthermore, 35.1% of participants, considered psychiatric consultation, at least slightly, but were hesitant to receive it due to the fear of contacting COVID-19 at the clinics. Instead, 54.4% of them preferred using digital therapeutics as an alternative to visiting offline clinics. CONCLUSION: We demonstrated that COVID-19 increased mental health problems along with access problems and identified their predictive factors. Digital therapeutics emerged as a viable solution to mental health problems and it was well-received by those in need of psychiatric consultation. Therefore, development and implementation of digital therapeutics should be considered to improve the mental health of people.

Altered Low Frequency Heart Rate Variability Associated with Agoraphobia in Panic Disorder: A Retrospective Study.

PURPOSE: This study aimed to compare the clinical features of panic disorder (PD) with comorbid agoraphobia to those of PD alone. We focused on autonomic nervous system (ANS) alterations reflected in heart rate variability (HRV) and executive function deficits reflected in the Stroop test. MATERIALS AND METHODS: We retrospectively compared psychometric features, Stroop test results, and resting-state HRV across three groups: a subclinical group with anxiety attack history, a PD group without agoraphobia, and a PD group with agoraphobia. The subclinical group included 10 male and 34 female, the PD without agoraphobia group included 17 male and 19 female, and the PD with agoraphobia group included 11 male and 18 female. RESULTS: The PD with agoraphobia group had higher Symptom Checklist-95 scores than the other groups. Both PD groups had longer reaction times in the Stroop test than the subclinical group. There were no significant differences in HRV parameters between the PD groups with and without agoraphobia. Compared with the subclinical group, the PD with agoraphobia group showed significantly lower values of the natural logarithm of low-frequency HRV. CONCLUSION: Our results do not support that executive function deficits and ANS alterations are more pronounced with comorbid agoraphobia among PD groups. However, PD with agoraphobia patients showed more complex and severe clinical symptoms in their self-reports. Compared with the subclinical group, PD patients with agoraphobia showed specific features in the natural logarithm of low-frequency HRV. Our findings suggest that agoraphobia comorbidity should be considered when evaluating or treating patients with PD.

Association between vision impairment and depression: a 9-year, longitudinal, nationwide, population-based cohort study in South Korea.

BACKGROUND/AIMS: Vision impairment (VI) increases the risk of various comorbidities, including depression. However, the relationship between depression and VI is unclear, and existing findings are inconsistent. We therefore investigated the risk of depression in adults before and after their registration as visually impaired. METHODS: In this longitudinal, nationwide, retrospective cohort study, 131 434 patients (aged ≥18 years) with newly registered VI during 2005-2013 were evaluated using the Korean National Health Insurance Service database. Using 1:1 propensity score matching, randomly selected patients (control group) were compared with patients with VI (patient group) according to age, sex, residential area and household income. Each patient was tracked from 3 years before and 5 years after registration. The risk of depression before and after VI registration was evaluated using a conditional logistic regression model. RESULTS: The risk of depression gradually increased from 3 years before registration (OR, 1.186; 95% CI 1.089 to 1.290), then peaked at the time of registration (OR, 1.925; 95% CI 1.788 to 2.073), and then gradually decreased until 5 years after registration (OR, 1.128; 95% CI 1.046 to 1.216). Male patients, those with severe VI and those aged 18-29 years had a higher risk of depression. CONCLUSIONS: Patients with VI had an increased risk of depression from 3 years before to 5 years after registration. Significant risk factors included severity, male sex and younger age. Thus, public mental health services are necessary to provide appropriate support and interventions to people before and after registration as visually impaired.

Severity identification for internet gaming disorder using heart rate variability reactivity for gaming cues: a deep learning approach.

Background: The diminished executive control along with cue-reactivity has been suggested to play an important role in addiction. Hear rate variability (HRV), which is related to the autonomic nervous system, is a useful biomarker that can reflect cognitive-emotional responses to stimuli. In this study, Internet gaming disorder (IGD) subjects' autonomic response to gaming-related cues was evaluated by measuring HRV changes in exposure to gaming situation. We investigated whether this HRV reactivity can significantly classify the categorical classification according to the severity of IGD. Methods: The present study included 70 subjects and classified them into 4 classes (normal, mild, moderate and severe) according to their IGD severity. We measured HRV for 5 min after the start of their preferred Internet game to reflect the autonomic response upon exposure to gaming. The neural parameters of deep learning model were trained using time-frequency parameters of HRV. Using the Class Activation Mapping (CAM) algorithm, we analyzed whether the deep learning model could predict the severity classification of IGD and which areas of the time-frequency series were mainly involved. Results: The trained deep learning model showed an accuracy of 95.10% and F-1 scores of 0.995 (normal), 0.994 (mild), 0.995 (moderate), and 0.999 (severe) for the four classes of IGD severity classification. As a result of checking the input of the deep learning model using the CAM algorithm, the high frequency (HF)-HRV was related to the severity classification of IGD. In the case of severe IGD, low frequency (LF)-HRV as well as HF-HRV were identified as regions of interest in the deep learning model. Conclusion: In a deep learning model using the time-frequency HRV data, a significant predictor of IGD severity classification was parasympathetic tone reactivity when exposed to gaming situations. The reactivity of the sympathetic tone for the gaming situation could predict only the severe group of IGD. This study suggests that the autonomic response to the game-related cues can reflect the addiction status to the game.

Evaluating the Modified Patient Health Questionnaire-2 and Insomnia Severity Index-2 for Daily Digital Screening of Depression and Insomnia: Validation Study.

BACKGROUND: The Patient Health Questionnaire-2 (PHQ-2) and Insomnia Severity Index-2 (ISI-2) are screening assessments that reflect the past 2-week experience of depression and insomnia, respectively. Retrospective assessment has been associated with reduced accuracy owing to recall bias. OBJECTIVE: This study aimed to increase the reliability of responses by validating the use of the PHQ-2 and ISI-2 for daily screening. METHODS: A total of 167 outpatients from the psychiatric department at the Yongin Severance Hospital participated in this study, of which 63 (37.7%) were male and 104 (62.3%) were female with a mean age of 35.1 (SD 12.1) years. Participants used a mobile app ("Mental Protector") for 4 weeks and rated their depressive and insomnia symptoms daily on the modified PHQ-2 and ISI-2 scales. The validation assessments were conducted in 2 blocks, each with a fortnight response from the participants. The modified version of the PHQ-2 was evaluated against the conventional scales of the Patient Health Questionnaire-9 and the Korean version of the Center for Epidemiologic Studies Depression Scale-Revised. RESULTS: According to the sensitivity and specificity analyses, an average score of 3.29 on the modified PHQ-2 was considered valid for screening for depressive symptoms. Similarly, the ISI-2 was evaluated against the conventional scale, Insomnia Severity Index, and a mean score of 3.50 was determined to be a valid threshold for insomnia symptoms when rated daily. CONCLUSIONS: This study is one of the first to propose a daily digital screening measure for depression and insomnia delivered through a mobile app. The modified PHQ-2 and ISI-2 were strong candidates for daily screening of depression and insomnia, respectively.

Reduced grip strength potentially indicates depression: Investigating multicontinental databases.

BACKGROUND: Multi-national studies in the association between handgrip strength and depression in middle and older aged adults are limited. Hence, Brazil, China, Europe, Korea, United Kingdom (UK) and United States (US) datasets were utilized to investigate this association. METHODS: A cross-sectional study was conducted with 51,285 participants aged >45 years. Handgrip strength scores were divided into quartiles, groups 1 (highest) to 4 (lowest) in each database, and depression measures converted to binary scores. RESULTS: Males in China and UK reported higher adjusted odds ratios (aORs) of depression for groups 2, 3, and 4 than for group 1. Brazil, US, and Korea reported greater aORs in groups 3 and 4 whereas Europe demonstrated increased aORs for group 4 only. Among females, China, Brazil, US, and Korea showed high aORs across all groups, while UK and Europe reported increased aORs for group 4 only. Highest ORs were reported from Korea in group 4 for males (aOR: 3·09; 95 % CI: 2·15-4·43; p < 0·001) and females (aOR: 3·74; 95 % CI: 2·78-5·03; p < 0·001). When removing the regional factor, aORs were higher in lower groups, with the highest reported from group 4 for males (aOR: 2·32; 95 % CI: 2·09-2·58; p < 0·001) and females (aOR: 2·11; 95 % CI: 1·95-2·29; p < 0·001). LIMITATIONS: Being a cross-sectional study, the results were not able to establish the causal direction between handgrip strength and depression. CONCLUSION: Lower handgrip strength was associated with an increased likelihood of depression. Early assessment of handgrip strength may identify populations at-risk for depression among middle and older aged adults.

Associations between Heart Rate Variability and Brain Activity during a Working Memory Task: A Preliminary Electroencephalogram Study on Depression and Anxiety Disorder.

Heart rate variability (HRV) has been suggested to reflect executive function and related neural activity. Executive dysfunction has been suggested to play an important role in the pathophysiology of emotional disorders. The purpose of this study was to investigate whether HRV showed a significant correlation with electroencephalogram (EEG) during a working memory performance in patients with depressive or anxiety disorder. A retrospective analysis was conducted with data from 61 patients with depressive disorder (43 women and 18 men) and 59 patients with anxiety disorder (35 women and 24 men). HRV was measured in the resting state, and EEG was recorded in the resting state and during the execution of a working memory task. It was performed in patients with depressive and anxiety disorder, and the paired sample t-test between resting state and task performance, as well as the partial correlation analysis between HRV and EEG, was conducted. Both depressed and anxious patients showed weaker beta relative power during the working memory task compared to the rest period. The resting-state EEG did not correlate with HRV parameters in both groups. In depressed patients, HRV showed a positive correlation with delta power during the task and a negative correlation with beta relative power during the task. In patients with anxiety disorder, HRV showed a significant positive correlation with theta power of the right frontal region during the task. Our results suggest that HRV would be related to executive-function-related neural activity in patients with depressive or anxiety disorder. Future studies with more subjects, including healthy controls, are needed to verify the correlation between HRV and EEG and to come up with a more comprehensive picture of neurobiological changes in emotional disorders.

Altered resting-state functional connectivity of the dorsal anterior cingulate cortex with intrinsic brain networks in male problematic smartphone users.

The excessive use of smartphones is associated with various medical complications and mental health problems. However, existing research findings on neurobiological mechanisms behind problematic smartphone use are limited. In this study, we investigated functional connectivity in problematic smartphone users, focusing on the default mode network (DMN) and attentional networks. We hypothesized that problematic smartphone users would have alterations in functional connectivity between the DMN and attentional networks and that such alterations would correlate with the severity of problematic smartphone use. This study included 30 problematic smartphone users and 35 non-problematic smartphone users. We carried out group independent component analysis (group ICA) to decompose resting-state functional magnetic resonance imaging (fMRI) data into distinct networks. We examined functional connectivity using seed-to-seed analysis and identified the nodes of networks in group ICA, which we used as region of interest. We identified greater functional connectivity of the dorsal anterior cingulate cortex (dACC) with the ventral attention network (VAN) and with the DMN in problematic smartphone users. In seed-to-seed analysis, problematic smartphone users showed atypical dACC-VAN functional connectivity which correlated with the smartphone addiction proneness scale total scores. Our resting-state fMRI study found greater functional connectivity between the dACC and attentional networks in problematic smartphone users. Our findings suggest that increased bottom-up and interoceptive attentional processing might play an important role in problematic smartphone use.

Orbitofrontal cortex functional connectivity changes in patients with binge eating disorder and bulimia nervosa.

We aimed to define the shared and unshared functional neurobiological underpinnings of binge eating disorder (BED) and bulimia nervosa (BN). These disorders both involve loss of control over binge eating, but differ based on purging behavior and body image distortion. BED and BN have also been found to show differences in brain activation patterns in reward sensitivity. We enrolled 13 and 12 drug-naive and medication-free women with BED and BN, respectively, and 22 age- and sex-matched healthy controls. We performed an orbitofrontal cortex (OFC)-seeded resting-state whole brain functional connectivity (FC) analysis among the groups. In this study, BED patients exhibited significantly higher impulsivity than controls, whereas the difference in impulsivity between BN and controls was not significant. Participants with BED and BN showed weaker FC between the left lateral OFC and the right precuneus than controls. In the BED only group, the FC strength between these regions was negatively correlated with self-reported impulsivity. In both BED and BN, FC between the left lateral OFC and the right dorsolateral prefrontal cortex was weaker than that in controls. In BED, FC between the left medial OFC and the right cerebellar lobule IV was stronger than that of other groups. Our current results suggest similarities and differences between BED and BN in OFC-seeded FC with respect to reward processing. In particular, FC of the OFC in BED patients showed a significant correlation with their high impulsivity, which may reflect a decline in executive control over binge eating.

Structural and functional brain alterations associated with cancer-associated cognitive decline in gastric cancer patients: A preliminary longitudinal neuroimaging study.

OBJECTIVE: Despite the clinical significance of cancer-associated cognitive decline (CACD), no longitudinal study has evaluated CACD in gastric cancer patients. This preliminary study explored structural and functional neural changes of CACD in gastric cancer patients focusing on the effects of chemotherapy. METHODS: 13 gastric cancer patients who received adjuvant chemotherapy (CTx+ group), 9 gastric cancer patients who did not receive adjuvant chemotherapy (CTx- group), and 10 healthy controls (HCs) were enrolled in this study. We performed self-report questionnaires, neurocognitive tests, voxel-based morphometry (VBM), and resting-state functional magnetic resonance imaging (rsfMRI) analyses before and 3 months after chemotherapy. RESULTS: Compared to the CTx- group, the CTx+ group exhibited statistically significant decrease in attention and executive function over time and dysfunction in delayed recognition performance. The results of the rsfMRI analysis showed a significant group-by-time interaction in the left hippocampus-anterior thalamus. However, no significant structural change was observed in the VBM analysis. CONCLUSION: To the best of our knowledge, this is the first longitudinal neuroimaging study on CACD in gastric cancer patients. Based on the results of our preliminary study, we suggest that the neuropathological processes and clinical presentation of CACD in gastric cancer patients is similar to those of patients associated with age-related neurodegenerative disorders.