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1.
EXCLI J ; 20: 1458-1473, 2021.
Article in English | MEDLINE | ID: mdl-34737688

ABSTRACT

Mild Cognitive Impairment (MCI) is fraught with high false positive diagnostic errors. The high rate of false positive diagnosis hampers attempts to identify reliable and valid biomarkers for MCI. Recent research suggests that aberrant functional neurocircuitries emerge prior to significant cognitive deficits. The aim of the present study was to examine this in clinically confirmed multi-domain amnestic-MCI (mdaMCI) using an established, multi-time point, methodology for minimizing false positive diagnosis. Structural and resting-state functional MRI data were acquired in healthy controls (HC, n=24), clinically-confirmed multi-domain amnestic-MCI (mdaMCI, n=14) and mild Alzheimer's Dementia (mAD, n=6). Group differences in cortical thickness, hippocampal volume and functional connectivity were investigated. Hippocampal subvolumes differentiated mAD from HC and mdaMCI. Functional decoupling of fronto-temporal networks implicated in memory and executive function differentiated HC and mdaMCI. Decreased functional connectivity in these networks was associated with poorer cognitive performance scores. Preliminary findings suggest the large-scale decoupling of fronto-temporal networks associated with cognitive decline precedes measurable structural neurodegeneration in clinically confirmed MCI and may represent a potential biomarker for disease progression.

2.
Psychol Rep ; 124(3): 1370-1383, 2021 Jun.
Article in English | MEDLINE | ID: mdl-32370598

ABSTRACT

While research has examined bystander responses in a traditional sense, there is a dearth of research regarding responses of cyberbystanders in a real-time situation, such as observing a cyberbullying scenario. This article describes a novel protocol designed to develop a series of images to be used to undertake research that aims to examine cyberbystander responses. A total of 24 scenarios (12 negative (cyberbullying) and 12 neutral) were created by the researchers and designed to mimic the way such scenarios would appear on a social networking site. The negative (cyberbullying) stimuli were rated in terms of level of severity, and the scenarios were compared to a selection of images from the International Affective Picture System using the Self-Assessment Manikin. These stimuli were compiled to form the Cyberbullying Picture Series (CyPicS). Through the development of the CyPicS, this protocol will aid future researchers in examining responses to real-life scenarios, as it is the first of its kind to develop these scenarios and test and evaluate them. CyPicS will provide researchers with the means to systematically evaluate responses to validated, real-life cyberbullying scenarios. More specifically, future researchers can utilize CyPicS to investigate how cyberbystanders respond when observing cyberbullying stimuli compared to neutral stimuli, as well as to measure and understand reactions or perceptions of cyberbullying. CyPicS can be used in any form of cyberbullying research (including electroencephalography and eye-tracking studies, psychological research, and functional magnetic resonance imaging studies) that may utilize bystander reactions and behaviors. Findings from research that utilizes CyPicS will greatly increase our understanding of bystander responses, and with variations in study design, researchers can further examine past or future associations with cyber-victim/bully status and mental health outcomes.


Subject(s)
Behavioral Research , Crime Victims , Cyberbullying , Adolescent , Adult , Female , Humans , Male , Young Adult
3.
Hum Brain Mapp ; 41(6): 1495-1504, 2020 04 15.
Article in English | MEDLINE | ID: mdl-31797458

ABSTRACT

There is a dearth of research that has investigated the neural correlates of cyberbullying, using task-based functional magnetic resonance imaging (fMRI) and, specifically, in a real-time context such as observing cyberbullying scenarios. This article presents pilot data from a novel protocol designed to undertake such research with the overall aim being to elucidate the neurobiological underpinnings of cyberbullying via task-based fMRI (tb-fMRI)) in passive cyberbystanders. Young adults (N = 32, 18 to 25 years old) viewed six negative (cyberbullying) and six neutral stimuli from the Cyberbullying Picture Series (CyPicS) while undergoing tb-fMRI. Our results revealed 12 clusters of significantly greater blood-oxygenation-level-dependent (BOLD) responses (family wise error corrected p FWE < .05) in participants when viewing cyberbullying stimuli compared to neutral stimuli, across a distributed network of regions including left and right middle temporal gyrus, default mode network hubs, left and right posterior cerebellum/vermis, and putamen. Further analysis also revealed greater BOLD response in females compared to males, as well as in those with no prior experience of cyberbullying compared to those with prior experience (despite gender), when viewing the cyberbullying stimuli compared to the neutral stimuli. These results bring us closer to understanding the neurobiological underpinnings that may be associated with cybervictim/bully status and outcomes.


Subject(s)
Cyberbullying/psychology , Adolescent , Adult , Age Factors , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Nerve Net/diagnostic imaging , Nerve Net/physiology , Oxygen/blood , Photic Stimulation , Pilot Projects , Self Report , Sex Characteristics , Young Adult
4.
Dev Neurosci ; 41(3-4): 193-202, 2019.
Article in English | MEDLINE | ID: mdl-31480044

ABSTRACT

The hippocampus and amygdala have justifiably been the focus of much mental health research due to their putative roles in top-down processing control of emotion, fear, and anxiety. However, understanding the causal relationship between these regions and mental illness has been limited as current literature is lacking in the observation of neuro-structural changes preceding first episodes. Here, we report whole and sub-structural hippocampal and amygdala volume correlates of psychological distress in early adolescence. Automated hippocampal subfield and amygdala nuclei segmentation was carried out in 32 participants (12-13 years old) recruited for the Longitudinal Adolescent Brain Study (LABS) who had psychological distress scores measured by the Kessler-10. Partial correlation analyses revealed significant negative association between left whole amygdala volume and psychological distress. Sub-structure analysis revealed that smaller left hippocampal CA1 volume and left basal and accessory basal amygdala nuclei volumes were all significantly associated with higher levels of psychological distress. Four-month follow-up analysis also revealed an association between change in K10 and CA1 volume suggesting a continued relationship between this hippocampal substructure and psychological distress. Grey matter volume of subcortical sub-structures involved within the hippocampal-basolateral amygdala-prefrontal cortex loop are highly correlated and are significantly reduced in adolescents with higher levels of psychological distress, indicating these nuclei and subfields play an important role in the emergence of mental illness.


Subject(s)
Amygdala/pathology , Anxiety/pathology , Hippocampus/pathology , Psychological Distress , Adolescent , Amygdala/physiopathology , Child , Female , Gray Matter/pathology , Hippocampus/physiopathology , Humans , Magnetic Resonance Imaging/methods , Male , Organ Size/physiology , Young Adult
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