Biology subjects

Fitzgibbon, B. M.

Publications and source records attributed to Fitzgibbon, B. M..

6 recordsLinked to original sources

bioRxiv2025

Attrition Rates in Mindfulness-Based Interventions for Chronic Pain: A Meta-Analysis

ObjectiveMindfulness-based interventions (MBIs) show promise in managing chronic pain but often require substantial time commitments, leading to high attrition rates and concerns about acceptability. This meta-analysis evaluated attrition rates in MBIs for chronic pain and explored factors contributing to participant withdrawal. MethodsFollowing PRISMA guidelines, 44 studies (45 intervention conditions) were analysed. Data on attrition rates, program characteristics (e.g., delivery method, group vs. individual therapy, session duration), and participant demographics were extracted. Meta-analyses of proportions assessed moderators influencing attrition rates. ResultsThe overall weighted mean attrition rate was 30.1% (95% CI: 24.5% to 37.3%) with substantial heterogeneity (I{superscript 2} = 89.0%). Stricter completion thresholds (defined as the minimum number of sessions required to be considered a programme completer) were associated with higher attrition (p < 0.001, R{superscript 2} = 28.1%), ranging from an 18% attrition rate for low thresholds (completion of [≥]3 sessions required to be defined as a completer) to a 49.7% attrition rate for high thresholds ([≥]6 sessions). Online delivery showed higher attrition rates (51.0%) compared to in-person delivery (25.6%, p = 0.002, R{superscript 2} = 17.1%). Individually delivered MBIs were also linked to higher attrition compared to group formats ({beta} = 0.216, p = 0.039, R{superscript 2} = 5.5%). ConclusionsAttrition rates for MBIs in chronic pain management vary widely. Higher attrition is associated with stricter completion criteria, online delivery, and individual formats. These findings highlight the need to optimise MBI programme structure to reduce attrition in MBIs for chronic pain management.

pathology↗

bioRxiv2024

Neural differences in conflict monitoring and stimulus expectancy processes in experienced meditators are likely driven by enhanced attention

ObjectivesMindfulness meditation has been linked to enhanced attention and executive function, likely resulting from practice-related effects on neural activity patterns. In this study, we used an event-related potential (ERP) paradigm to examine brain responses related to conflict monitoring and attention in experienced mindfulness meditators to better understand key factors driving meditation-related effects. MethodsWe measured electroencephalography-derived N2 and P3 ERPs reflecting conflict monitoring and attention processes from 35 meditators and 29 non-meditators across both an easy and a hard Go/Nogo task (50% Nogo and 25% Nogo stimuli, respectively). ResultsMeditators displayed distinct neural activity patterns compared to non-meditators, with enhanced N2 responses in fronto-midline electrodes following hard Nogo trials (pFDR = 0.011, np2 = 0.111). The fronto-midline N2 ERP was also larger following Nogo trials than Go trials, in the harder task condition, and was related to correct responses. Meditators also exhibited a more frontally distributed P3 ERP in the easy task compared to the hard task, while non-meditators showed a more frontally distributed P3 ERP in the hard task (pFDR = 0.015, np2 = 0.079). ConclusionsMindfulness meditation was associated with distinct topographical patterns of neural activity in the attention task, without corresponding increases in global neural activity amplitudes. These meditation-related effects appear to be driven by attention-specific mechanisms, despite the examined neural activity being associated with conflict monitoring and stimulus expectancy. Our findings suggest that the cognitive benefits of meditation may only emerge in tasks that actively engage targeted cognitive processes, such as sustained attention.

neuroscience↗

bioRxiv2024

Experienced meditators show greater forward travelling cortical alpha wave strengths

Mindfulness meditation involves training attention, commonly towards the current sensory experience, with an attitude of non-judgemental awareness. Theoretical perspectives suggest meditation alters the brains predictive processing mechanisms, increasing the synaptic gain and precision with which sensory information is processed, and reducing the generation or elaboration of higher-order beliefs. Recent research suggests that forwards and backwards travelling cortical alpha waves provide an indication of these predictive processing functions. Here, we used electroencephalography (EEG) to test whether the strength of forwards and backwards travelling cortical alpha waves differed between experienced meditators and a matched sample of non-meditators, both during an eyes-closed resting state (N = 97) and during a visual cognitive (Go/No-go) task (N = 126). Our results showed that meditators produced stronger forwards travelling cortical alpha waves compared to non-meditators, both while resting with their eyes closed and during task performance. Meditators also exhibited weaker backwards travelling cortical alpha wave strength while resting with their eyes closed. These results may be indicative of a neural mechanism underpinning enhanced attention associated with meditation practice, as well as a potential neural marker of the reductions in resting mind-wandering that are suggested to be associated with meditation practice. The results also support models of brain function that suggest attention modification can be achieved by mental training aimed at increased processing of sensory information, which might be indexed by greater strength of forwards travelling cortical alpha waves.

neuroscience↗

bioRxiv2024

EEG is better when cleaning effectively targets artifacts

Electroencephalography (EEG) is a useful tool to measure neural activity. However, EEG data are usually contaminated with non-neural artifacts, including voltage shifts generated by eye movements and muscle activity, and other artifacts that are less easily characterizable. The confounding influence of artifacts is often addressed by decomposing data into components, subtracting probable artifactual components, then reconstructing data back into the electrode space. This approach is commonly applied using independent component analysis (ICA). Here, we demonstrate the counterintuitive finding that due to imperfect component separation, component subtraction can artificially inflate effect sizes for event-related potentials (ERPs) and connectivity measures, bias source localisation estimates, and remove neural signals. To address this issue, we developed a method that targets cleaning to the artifact periods of eye movement components and artifact frequencies of muscle components. When tested across different EEG systems and cognitive tasks, our results showed that the targeted artifact reduction method is effective in cleaning artifacts while also reducing the artificial inflation of ERP and connectivity effect sizes and minimizing source localisation biases. Our results suggest EEG pre-processing is better when targeted cleaning is applied, as this improves preservation of neural signals and mitigates effect size inflation and source localisation biases that result from approaches which subtract artifact components across the entire time-series. These improvements enhance the reliability and validity of EEG data analysis. Our method is provided in the freely available RELAX pipeline, which includes a graphical user interface for ease of use and is available as an EEGLAB plugin (https://github.com/NeilwBailey/RELAX).

neuroscience↗

bioRxiv2021

A single- and paired-pulse TMS-EEG investigation of the N100 and long interval cortical inhibition in autism spectrum disorder

BackgroundThere is evidence to suggest a disruption of gamma-aminobutyric acid (GABA) in autism spectrum disorder (ASD), but findings are mixed. Concurrent electroencephalography and transcranial magnetic stimulation (TMS-EEG) provides a novel method by which to probe GABA-mediated cortical inhibition. MethodsWith a particular focus on GABAB-ergic mechanisms, we investigated the N100 peak of the TMS evoked potential (TEP), as well as long interval cortical inhibition (LICIEEG) in adults with ASD (n = 23; 12 female) without intellectual disability, and a neurotypical comparison group (n =22; 12 female) matched for age, sex, and IQ. Seventy-five single-(spTMS) and 75 paired-(ppTMS; 100 ms inter-stimulus-interval) pulses were applied to the right primary motor cortex (M1), right temporoparietal junction (TPJ), and right dorsolateral prefrontal cortex (DLPFC) while EEG was recorded from 20 scalp electrodes. Additionally, electromyography (EMG) was used to investigate corticospinal inhibition following ppTMS to M1 (LICIEMG). ResultsThere were no group differences in the N100 amplitude or latency following spTMS. LICI outcomes following ppTMS, as measured by either EEG or EMG, also did not differ between groups. These findings were further supported by Bayesian analyses, which provided weak-moderate support for the null hypothesis. LimitationsData presented here reflect adults without intellectual disability, and the generalisability of these results is therefore limited. ConclusionsThe findings of this study argue against GABAB-ergic impairment in adults with ASD without intellectual disability, at least at the cortical regions examined. Further research investigating these mechanisms in ASD at various ages, with varying degrees of symptomatology, and at different brain sites is an important factor in understating the role of GABA in the neuropathophysiology of ASD.

neuroscience↗

bioRxiv2019

Mindfulness meditation alters neural activity underpinning working memory during tactile distraction

Evidence suggests that mindfulness meditation (MM) improves selective attention and reduces distractibility by enhancing top-down neural modulation. Altered P300 and alpha neural activity from MM have been identified and may reflect the neural changes that underpin these improvements. Given the proposed role of alpha activity in supressing processing of task-irrelevant information, it is theorised that altered alpha activity may underlie increased availability of neural resources in meditators. The present study investigated attentional function in meditators using a cross-modal study design, examining the P300 during working memory (WM) and alpha activity during concurrent distracting tactile stimuli. Thirty-three meditators and 27 healthy controls participated in the study. Meditators showed a more frontal distribution of P300 neural activity following WM stimuli (p = 0.005, {eta}{superscript 2} = 0.060) and more modulation of alpha activity at parietal-occipital regions between single (tactile stimulation only) and dual task demands (tactile stimulation plus WM task) (p < 0.001, {eta}{superscript 2} = 0.065). Additionally, meditators performed more accurately than controls (p = 0.038, {eta}{superscript 2} = 0.067). The altered distribution of neural activity concurrent with improved WM performance suggests greater attentional resources dedicated to task related functions such as WM in meditators. Thus, meditation-related neural changes are likely multi-faceted involving both altered distribution and also amplitudes of brain activity, enhancing attentional processes depending on task requirements.

neuroscience↗