scholarly journals The neurobiology of smartphone addiction in emerging adults evaluated using brain morphometry and resting-state functional MRI

2021 ◽  
Vol 4 (4) ◽  
pp. 19-28
Author(s):  
Aida Abdul Rashid ◽  
Subapriya Suppiah ◽  
Nisha Syed Nasser ◽  
Hamed Sharifat ◽  
Mazlyfarina Mohamad ◽  
...  

The characteristics of smartphone addiction (SPA) can be evaluated by neuroimaging studies. Information on the brain structural alterations, and effects on psychosocial wellbeing, however, have not been concurrently evaluated. The aim of this study was to identify abnormalities in gray matter volume using voxel-based morphometry (VBM) and neuronal functional alterations using resting-state functional MRI (rs-fMRI) in emerging adults with SPA.  We correlated the neuroimaging parameters with indices for psychosocial wellbeing such as depression, anxiety, stress, and impulsivity. Forty participants (20 SPA and 20 age-matched healthy controls) were assessed using VBM and rs-fMRI. The smartphone addiction scale – Malay version (SAS-M) questionnaire scores were used to categorize the SPA and healthy control groups. DASS-21 and BIS-11 questionnaires were used to assess for psychosocial wellbeing and impulsivity, respectively.  VBM identified the SPA group to have reduced gray matter volume in the insula and precentral gyrus; and increased grey matter volume in the precuneus relative to controls. Moderate correlation was observed between the precuneus volume and the SAS-M scores. Individuals with SPA showed significant rs-fMRI activations in the precuneus, and posterior cingulate cortex (FWE uncorrected, p<0.001). The severity of SPA was correlated with depression. Anxiety score was moderately correlated with reduced GMV at the precentral gyrus. Collectively, these results can be used to postulate that the structural and neuronal functional changes in the insula are linked to the neurobiology of SPA that shares similarities with other behavioural addictions.

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
M. Lotze ◽  
M. Domin ◽  
C. O. Schmidt ◽  
N. Hosten ◽  
H. J. Grabe ◽  
...  

Abstract Income and education are both elements of a person’s socioeconomic status, which is predictive of a broad range of life outcomes. The brain’s gray matter volume (GMV) is influenced by socioeconomic status and mediators related to an unhealthy life style. We here investigated two independent general population samples comprising 2838 participants (all investigated with the same MRI-scanner) with regard to the association of indicators of the socioeconomic status and gray matter volume. Voxel-based morphometry without prior hypotheses revealed that years of education were positively associated with GMV in the anterior cingulate cortex and net-equivalent income with gray matter volume in the hippocampus/amygdala region. Analyses of possible mediators (alcohol, cigarettes, body mass index (BMI), stress) revealed that the relationship between income and GMV in the hippocampus/amygdala region was partly mediated by self-reported stressors, and the association of years of education with GMV in the anterior cingulate cortex by BMI. These results corrected for whole brain effects (and therefore not restricted to certain brain areas) do now offer possibilities for more detailed hypotheses-driven approaches.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Haixia Zheng ◽  
Bart N. Ford ◽  
Rayus Kuplicki ◽  
Kaiping Burrows ◽  
Peter W. Hunt ◽  
...  

AbstractHuman cytomegalovirus (HCMV) is a neurotropic herpes virus known to cause neuropathology in patients with impaired immunity. Previously, we reported a reduction in the gray matter volume (GMV) of several brain regions in two independent samples of participants who were seropositive for HCMV (HCMV+) compared to matched participants who were seronegative for HCMV (HCMV−). In addition to an independent replication of the GMV findings, this study aimed to examine whether HCMV+ was associated with differences in resting-state functional connectivity (rsfMRI-FC). After balancing on 11 clinical/demographic variables using inverse probability of treatment weighting (IPTW), GMV and rsfMRI-FC were obtained from 99 participants with major depressive disorder (MDD) who were classified into 42 HCMV+ and 57 HCMV− individuals. Relative to the HCMV− group, the HCMV+ group showed a significant reduction of GMV in nine cortical regions. Volume reduction in the right lateral orbitofrontal cortex (standardized beta coefficient (SBC) = −0.32, [95%CI, −0.62 to −0.02]) and the left pars orbitalis (SBC = −0.34, [95%CI, −0.63 to −0.05]) in the HCMV+ group was also observed in the previous study. Regardless of the parcellation method or analytical approach, relative to the HCMV− group, the HCMV+ group showed hypoconnectivity between the hubs of the sensorimotor network (bilateral postcentral gyrus) and the hubs of the salience network (bilateral insula) with effect sizes ranging from SBC = −0.57 to −0.99. These findings support the hypothesis that a positive HCMV serostatus is associated with altered connectivity of regions that are important for stress and affective processing and further supports a possible etiological role of HCMV in depression.


SLEEP ◽  
2020 ◽  
Vol 43 (Supplement_1) ◽  
pp. A119-A119
Author(s):  
I Anlap ◽  
E Taylor ◽  
M A Grandner ◽  
W D Killgore

Abstract Introduction Vulnerability to sleep deprivation (SD) has been attributed to inter-individual trait-like differences in the ability to sustain vigilance and subjective alertness, which may have distinct neurobiological substrates. We have previously shown that reduced suppression of the Default Mode Network (DMN) during a cognitive task was predictive of global vulnerability to SD. However, little is known about vulnerability to mood decrements during SD and the underlying neurobiological mechanisms. Using voxel-based morphometry (VBM), we assessed structural differences in gray matter volume (GMV) of a region of the anterior DMN, the medial prefrontal cortex and its association with self-reported mood during 29 hours of SD. Methods 45 healthy participants (23 male; Ages 20-43) underwent 3T structural magnetic resonance imaging (MRI). Within 4 days, participants underwent an overnight SD session (29 hours awake total) which included hourly mood assessments with several visual analog mood scales (VAMS) assessing positive and negative affect. Hourly VAMS data were converted into a comparative metric of percent worsening of mood scores from 19:00 until noon the next day. These scores were averaged to determine a “mood resilience” score, with higher scores indicating greater mood sustainment. Using SPM12, the mean mood resilience scores were correlated with whole-brain gray matter volume, restricted to the medial prefrontal cortex, p&lt;.05, FWE corrected, with a cluster threshold of 137 voxels. Results Overnight mood resilience was significantly correlated with greater grey matter volume in right rostral medial prefrontal cortex (p&lt;.05, corrected; k=137). Conclusion Individuals with greater gray matter volume within a circumscribed region of the right medial prefrontal cortex demonstrated greater resilience to mood degradation over 29 hours of continuous wakefulness. This same region of the brain has been shown to be critical for the passive maintenance of emotions. We speculate that greater GMV could protect against mood decline by better sustaining emotional state during SD. Support Defense Advanced Research Projects Agency Young Faculty Award: DARPA-12-12-11-YFA11-FP-029


SLEEP ◽  
2020 ◽  
Vol 43 (Supplement_1) ◽  
pp. A116-A116
Author(s):  
C E Meinhausen ◽  
J R Vanuk ◽  
M A Grandner ◽  
W D Killgore

Abstract Introduction Sleep deprivation has often been associated with decreased cognitive control, including deficits in the ability to sustain attention. Psychomotor vigilance speed slows following a period of fatigue, and can lead to disastrous results in daily life. In order to determine the brain areas correlated with reduced psychomotor vigilance speed, as a result of diminished sleep, a voxel-based morphometry analysis was performed prior to a period of monitored sleep deprivation. The mean speed of response time during the final 17 hours of a 29-hour sleep deprivation was then measured with the Psychomotor Vigilance Test (PVT), a reaction-timed task that measures the speed participants respond to a visual stimulus. Methods 45 healthy individuals (male=23 female=22) between the ages of 20-43 years (M=25.4 SD=5.6) participated in the study. Structural neuroimaging data were collected using a T3 magnetic resonance imaging scanner following a typical night’s sleep. Mean PVT speed was monitored with an hourly 10-minute PVT assessment during a monitored overnight sleep deprivation session. Speed was defined as the reciprocal of reaction time (1/RT). Results PVT speed was negatively correlated with grey matter volume (P&lt;.05 FWE-corrected) in the prefrontal cortex, specifically the right posterior inferior frontal gyrus (p=.030; MNI coordinates = 36, 12, 26). Conclusion Our findings indicate that gray matter within the right posterior inferior frontal gyrus is greater in individuals who are more vulnerable to slowing of PVT responses during an overnight period of sleep deprivation. These findings suggest that inter-individual differences in the ability to sustain psychomotor vigilance during sleep loss may be related to increased gray matter in the right lateral prefrontal cortex and could have implications for understanding the neurobiological substrates of vulnerability and resilience to sleep loss. Support  


PLoS ONE ◽  
2017 ◽  
Vol 12 (10) ◽  
pp. e0186463 ◽  
Author(s):  
Raquel García-García ◽  
Álvaro Javier Cruz-Gómez ◽  
Alba Mangas-Losada ◽  
Amparo Urios ◽  
Cristina Forn ◽  
...  

BMC Medicine ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Sehoon Park ◽  
Soojin Lee ◽  
Yaerim Kim ◽  
Semin Cho ◽  
Kwangsoo Kim ◽  
...  

Abstract Background Atrial fibrillation (AF) and brain volume loss are prevalent in older individuals. We aimed to assess the causal effect of atrial fibrillation on brain volume phenotypes by Mendelian randomization (MR) analysis. Methods The genetic instrument for AF was constructed from a previous genome-wide association study (GWAS) meta-analysis (15,993 AF patients and 113,719 controls of European ancestry). The outcome summary statistics for head-size-normalized white or gray matter volume measured by magnetic resonance imaging were provided by a previous GWAS of 33,224 white British participants in the UK Biobank. Two-sample MR by the inverse variance–weighted method was performed, supported by pleiotropy-robust MR sensitivity analysis. The causal estimates for the effect of AF on ischemic stroke were also investigated in a dataset that included the findings from the MEGASTROKE study (34,217 stroke patients and 406,111 controls of European ancestry). The direct effects of AF on brain volume phenotypes adjusted for the mediating effect of ischemic stroke were studied by multivariable MR. Results A higher genetic predisposition for AF was significantly associated with lower grey matter volume [beta −0.040, standard error (SE) 0.017, P=0.017], supported by pleiotropy-robust MR sensitivity analysis. Significant causal estimates were identified for the effect of AF on ischemic stroke (beta 0.188, SE 0.026, P=1.03E−12). The total effect of AF on lower brain grey matter volume was attenuated by adjusting for the effect of ischemic stroke (direct effects, beta −0.022, SE 0.033, P=0.528), suggesting that ischemic stroke is a mediator of the identified causal pathway. The causal estimates were nonsignificant for effects on brain white matter volume as an outcome. Conclusions This study identified that genetic predisposition for AF is significantly associated with lower gray matter volume but not white matter volume. The results indicated that the identified total effect of AF on gray matter volume may be mediated by ischemic stroke.


Sign in / Sign up

Export Citation Format

Share Document