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1.
Appl Ergon ; 122: 104382, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39265503

RESUMEN

The introduction of advanced digital technologies continues to increase system complexity and introduce risks, which must be proactively identified and managed to support system resilience. Brain-computer interfaces (BCIs) are one such technology; however, the risks arising from broad societal use of the technology have yet to be identified and controlled. This study applied a structured systems thinking-based risk assessment method to prospectively identify risks and risk controls for a hypothetical future BCI system lifecycle. The application of the Networked Hazard Analysis and Risk Management System (Net-HARMS) method identified over 800 risks throughout the BCI system lifecycle, from BCI development and regulation through to BCI use, maintenance, and decommissioning. High-criticality risk themes include the implantation and degradation of unsafe BCIs, unsolicited brain stimulation, incorrect signals being sent to safety-critical technologies, and insufficiently supported BCI users. Over 600 risk controls were identified that could be implemented to support system safety and performance resilience. Overall, many highly-impactful BCI system safety and performance risks may arise throughout the BCI system lifecycle and will require collaborative efforts from a wide range of BCI stakeholders to adequately control. Whilst some of the identified controls are practical, work is required to develop a more systematic set of controls to best support the design of a resilient sociotechnical BCI system.

2.
Front Endocrinol (Lausanne) ; 15: 1345527, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863930

RESUMEN

Background: Given its putative roles in mediating prosocial behavior, attachment bonds, and stress physiology, oxytocin modulation has been hypothesized to be a biological correlate of the salubrious effects of meditation practice. Here we investigated the effects of a month-long silent meditation retreat on changes in oxytocin, and the related hormone and vasopressin, in relation to psychosocial changes in attachment style, anxiety, personality measures, and feelings of social connectedness with fellow meditators. Methods: Plasma oxytocin and vasopressin and self-report questionnaires were measured in retreat participants (n = 28) at the beginning of, and 3 weeks into, a residential meditation retreat. Control participants (n = 34), who were similar in age, gender, and meditation experience, were also assessed across a 3-week interval. Linear mixed effects models were used to assess outcomes. Results: The retreat group showed a small but significant decrease in oxytocin compared to controls who showed no change. In the retreat group, higher openness to experience at Time 1 predicted greater reductions in oxytocin during the retreat, and lower oxytocin at Time 2 was related to stronger feelings of personal connection with fellow meditators. The changes in oxytocin were not related to attachment style or anxiety. Vasopressin decreased over time across both groups, suggesting no specific effect of retreat. Conclusion: These preliminary findings suggest that meditation training in the context of a silent residential retreat may reduce circulating levels of oxytocin. We interpret this finding from multiple theoretical perspectives, discussing key measurement limitations and proposing future study designs that may help to differentiate the effects of different meditation practices and contexts on oxytocin signaling.


Asunto(s)
Meditación , Oxitocina , Vasopresinas , Humanos , Oxitocina/sangre , Meditación/psicología , Femenino , Masculino , Adulto , Persona de Mediana Edad , Vasopresinas/sangre , Ansiedad/sangre , Ansiedad/psicología
3.
Appl Ergon ; 117: 104245, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38320386

RESUMEN

There are concerns that Artificial General Intelligence (AGI) could pose an existential threat to humanity; however, as AGI does not yet exist it is difficult to prospectively identify risks and develop requisite controls. We applied the Work Domain Analysis Broken Nodes (WDA-BN) and Event Analysis of Systemic Teamwork-Broken Links (EAST-BL) methods to identify potential risks in a future 'envisioned world' AGI-based uncrewed combat aerial vehicle system. The findings suggest five main categories of risk in this context: sub-optimal performance risks, goal alignment risks, super-intelligence risks, over-control risks, and enfeeblement risks. Two of these categories, goal alignment risks and super-intelligence risks, have not previously been encountered or dealt with in conventional safety management systems. Whereas most of the identified sub-optimal performance risks can be managed through existing defence design lifecycle processes, we propose that work is required to develop controls to manage the other risks identified. These include controls on AGI developers, controls within the AGI itself, and broader sociotechnical system controls.


Asunto(s)
Inteligencia Artificial , Administración de la Seguridad , Humanos , Estudios Prospectivos , Medición de Riesgo , Inteligencia
4.
World Neurosurg ; 184: 14, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38185454

RESUMEN

Vertebral artery (VA) stenosis is a cause of vertebrobasilar insufficiency (VBI) and disabling posterior circulation stroke,1 accounting for up to 30% of all strokes.2 Although the natural history of VBI is not as well delineated as that of carotid stenosis, strokes in the basilar circulation can be more disabling than their anterior circulation counterparts. Stenosis exceeding 30% at the origin of the vertebral artery is associated with increased risk of stroke.3 The authors present a case of a female patient with significant peripheral vascular disease who presented with concerns for VBI. The patient was on antiplatelet and anticoagulative medications and a statin at the time of her presentation. Angiography demonstrated bilateral vertebral artery origin stenosis. The left VA was diminutive and arose directly from the arch (Video 1). The right VA demonstrated critical stenosis at its origin. Attempts at endovascular access of the right VA for placement of a balloon-mounted stent were unsuccessful. The patient underwent a transcervical approach for endarterectomy of the VA origin. The VA can be readily accessed using a small supraclavicular incision to isolate the V1 segment of the vessel. The procedure was performed with the patient heparinized and on antiplatelet medications. Alternatives to this strategy include patch grafting in addition to the endarterectomy or use of a short vein graft to bypass the stenosis of the VA beyond the stenotic segment.


Asunto(s)
Accidente Cerebrovascular , Insuficiencia Vertebrobasilar , Humanos , Femenino , Arteria Vertebral/diagnóstico por imagen , Arteria Vertebral/cirugía , Constricción Patológica , Insuficiencia Vertebrobasilar/complicaciones , Insuficiencia Vertebrobasilar/diagnóstico por imagen , Insuficiencia Vertebrobasilar/cirugía , Endarterectomía
5.
World Neurosurg ; 184: 40, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38219801

RESUMEN

With improvements in anesthesia, monitoring, and peroperative care, the surgical removal of intrinsic brainstem pathology has become a possibility.1 Although surgical removal of deep-seated lesions continues to have significant morbidity, at least temporarily, associated with it, removal of exophytic lesions can be accomplished with little disability for the patient. The key to a good outcome, when removing cerebral cavernous malformation, is preservation of adjacent neurovascular bundles, use of sharp dissection over blunt pulling, judicious use of cautery in and around the brainstem, and preservation of the developmental venous anomaly, when present. The authors present a case of a lateral pontine cerebral cavernous malformation that was exophytic at the lateral and peritrigeminal safe entry zones.2 Neuromonitoring was used an adjunct to ensure safety of the procedure. The lesion is accessed using a keyhole retrosigmoid craniotomy (Video 1). We do not routinely use lumbar drains for these procedures as careful arachnoid dissection can result in adequate cerebrospinal fluid release. The window of access to this area is between CN 5 and the CN 7/8 complex. The arachnoid over the nerves is preserved, but the layer between the nerves is exposed to gain access to the lateral pons. The lesion is sharply dissected from the lateral pons, taking care to save the developmental venous anomaly, from which this lesion arises.


Asunto(s)
Hemangioma Cavernoso del Sistema Nervioso Central , Humanos , Hemangioma Cavernoso del Sistema Nervioso Central/diagnóstico por imagen , Hemangioma Cavernoso del Sistema Nervioso Central/cirugía , Hemangioma Cavernoso del Sistema Nervioso Central/patología , Puente/diagnóstico por imagen , Puente/cirugía , Puente/patología , Craneotomía/métodos , Tronco Encefálico/cirugía , Procedimientos Neuroquirúrgicos/métodos
7.
Foot Ankle Spec ; : 19386400231209652, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37982456

RESUMEN

OBJECTIVE: We sought to assess whether the presence of an os peroneum is correlated with cavovarus foot alignment in patients without a neurologic explanation for their foot shape. We hypothesized that a large os peroneum would increase the power of the peroneus longus and lead to a forefoot-driven, hindfoot varus deformity. MATERIALS AND METHODS: This was a retrospective cohort study conducted at a single institution and reviewed patients with 3 weightbearing views of the foot on plain radiography. Patients were characterized into having either no os peroneum (235), a small os peroneum (18), or a large os peroneum (23). The control group included the first 101 of the 235 patients without an os peroneum based on a power analysis of the primary outcome, which was the difference in the mean Meary's angle (lateral talo-first metatarsal angle) between groups. The kite angle (anterior-posterior [AP] talocalcaneal angle), as well as 4 other angles were measured as secondary outcomes. RESULTS: Those with a large os peroneum had on a mean 7.7° (P < .01) more apex dorsal angulation of Meary's angle than controls, and a kite angle 4.2° varus to that of the control group. There were no differences between the small os peroneum and control groups. CONCLUSION: These findings add to the existing literature surrounding the etiology of cavovarus foot shape and link the presence of an ossified os peroneum, an oftentimes incidental radiographic finding, to cavovarus foot deformity in those without an underlying neurologic diagnosis. LEVELS OF EVIDENCE: Therapeutic, Level III: Retrospective Case-Control.

8.
J Exp Psychol Gen ; 152(10): 2897-2924, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37166841

RESUMEN

Contemplative traditions have long affirmed that compassion and kindness are trainable skills. While research on meditation practice has recently flourished, the mechanisms that might engender such changes are still poorly understood. Here, we present a motivational framework to explain why meditation training should increase concern for others and modulate empathic engagement with human suffering over time. Meditation practices are conceived as tools for enacting cognitive and emotion regulatory goals that are conditioned by the underlying ethical motivation of the training-to reduce and alleviate suffering. In support of this account, we present data from a randomized, wait-list-controlled study of intensive meditation. In Study 1, we use a novel cardiovascular index to show that 3 months of meditation training can increase the motivational salience of others' suffering, as compared to the salience of threats to oneself. In Study 2, we demonstrate that training-related changes in the ability to orient attention to suffering are mediated by the dynamic regulation of distress-related physiological arousal. Finally, in Study 3, we provide exploratory evidence suggesting that meditation training may influence how human suffering is encoded in memory, leaving lasting imprints on the recollection of emotional experience. Together, our findings suggest that meditation training can strengthen the motivational relevance of others' suffering, prompting a shift from self-focused to other-focused evaluative processing. Considering meditation training from a motivational standpoint offers an important perspective for understanding how compassion can be cultivated through intentional practice. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Meditación , Humanos , Meditación/psicología , Emociones/fisiología , Empatía
9.
Foot Ankle Clin ; 28(2): 427-444, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37137632

RESUMEN

Acute and chronic subtalar instability and commonly coexistent with other hindfoot pathology but can be difficult to diagnose. A high degree of clinical suspicion is required as most imaging modalities and clinical maneuvers are poor at detecting isolated subtalar instability. The initial treatment is similar to ankle instability, and a wide variety of operative interventions have been presented in the literature for persistent instability. Outcomes are variable and limited.


Asunto(s)
Inestabilidad de la Articulación , Articulación Talocalcánea , Humanos , Inestabilidad de la Articulación/diagnóstico , Inestabilidad de la Articulación/cirugía , Articulación Talocalcánea/cirugía , Pie , Articulación del Tobillo/cirugía
10.
Appl Ergon ; 111: 104028, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37148587

RESUMEN

Brain-computer interface (BCI) technologies are progressing rapidly and may eventually be implemented widely within society, yet their risks have arguably not yet been comprehensively identified, nor understood. This study analysed an anticipated invasive BCI system lifecycle to identify the individual, organisational, and societal risks associated with BCIs, and controls that could be used to mitigate or eliminate these risks. A BCI system lifecycle work domain analysis model was developed and validated with 10 subject matter experts. The model was subsequently used to undertake a systems thinking-based risk assessment approach to identify risks that could emerge when functions are either undertaken sub-optimally or not undertaken at all. Eighteen broad risk themes were identified that could negatively impact the BCI system lifecycle in a variety of unique ways, while a larger number of controls for these risks were also identified. The most concerning risks included inadequate regulation of BCI technologies and inadequate training of BCI stakeholders, such as users and clinicians. In addition to specifying a practical set of risk controls to inform BCI device design, manufacture, adoption, and utilisation, the results demonstrate the complexity involved in managing BCI risks and suggests that a system-wide coordinated response is required. Future research is required to evaluate the comprehensiveness of the identified risks and the practicality of implementing the risk controls.


Asunto(s)
Interfaces Cerebro-Computador , Humanos , Estudios Prospectivos , Medición de Riesgo , Electroencefalografía/métodos
11.
PLoS One ; 17(12): e0279033, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36512600

RESUMEN

Patients with heart failure (HF) often suffer from multimorbidity. Rapid assessment of multimorbidity is important for minimizing the risk of harmful drug-disease and drug-drug interactions. We assessed the accuracy of using the electronic health record (EHR) problem list to identify comorbid conditions among patients with chronic HF in the emergency department (ED). A retrospective chart review study was performed on a random sample of 200 patients age ≥65 years with a diagnosis of HF presenting to an academic ED in 2019. We assessed participant chronic conditions using: (1) structured chart review (gold standard) and (2) an EHR-based algorithm using the problem list. Chronic conditions were classified into 37 disease domains using the Agency for Healthcare Research Quality's Elixhauser Comorbidity Software. For each disease domain, we report the sensitivity, specificity, positive predictive value, and negative predictive of using an EHR-based algorithm. We calculated the intra-class correlation coefficient (ICC) to assess overall agreement on Elixhauser domain count between chart review and problem list. Patients with HF had a mean of 5.4 chronic conditions (SD 2.1) in the chart review and a mean of 4.1 chronic conditions (SD 2.1) in the EHR-based problem list. The five most prevalent domains were uncomplicated hypertension (90%), obesity (42%), chronic pulmonary disease (38%), deficiency anemias (33%), and diabetes with chronic complications (30.5%). The positive predictive value and negative predictive value of using the EHR-based problem list was greater than 90% for 24/37 and 32/37 disease domains, respectively. The EHR-based problem list correctly identified 3.7 domains per patient and misclassified 2.0 domains per patient. Overall, the ICC in comparing Elixhauser domain count was 0.77 (95% CI: 0.71-0.82). The EHR-based problem list captures multimorbidity with moderate-to-good accuracy in patient with HF in the ED.


Asunto(s)
Insuficiencia Cardíaca , Multimorbilidad , Humanos , Anciano , Registros Electrónicos de Salud , Estudios Retrospectivos , Insuficiencia Cardíaca/epidemiología , Servicio de Urgencia en Hospital , Enfermedad Crónica
12.
Mindfulness (N Y) ; 13(10): 2488-2506, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36258902

RESUMEN

Objectives: A core assumption of meditation training is that cognitive capacities developed during formal practice will transfer to other contexts or activities as expertise develops over time. This implies that meditation training might influence domain-general neurocognitive systems, the spontaneous activity of which should be reflected in the dynamics of the resting brain. Previous research has demonstrated that 3 months of meditation training led to reductions in EEG beta band power during mindfulness of breathing practice. The current study extends these findings to ask whether concomitant shifts in power are observed during 2 min of eyes closed rest, when participants are not explicitly engaged in formal meditation. Methods: Experienced meditation practitioners were randomly assigned to practice 3 months of focused attention meditation in a residential retreat, or to serve as waitlist controls. The waitlist controls later completed their own 3-month retreat. Permutation-based cluster analysis of 88-channel resting EEG data was used to test for spectral changes in spontaneous brain activity over the course of the retreats. Results: Longitudinal reductions in EEG power in the beta frequency range were identified and replicated across the two independent training periods. Less robust reductions were also observed in the high alpha frequency range, and in individual peak alpha frequency. These changes closely mirror those previously observed during formal mindfulness of breathing meditation practice. Conclusions: These findings suggest that the neurocognitive effects of meditation training can extend beyond the bounds of formal practice, influencing the spontaneous activity of the resting brain. Rather than serving as an invariant baseline, resting states might carry meaningful training-related effects, blurring the line between state and trait change. Supplementary Information: The online version contains supplementary material available at 10.1007/s12671-022-01974-9.

13.
Compr Psychoneuroendocrinol ; 11: 100152, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35818436

RESUMEN

Background: Meditation retreats are characterized by intensive or concentrated periods of meditation practice, commonly undertaken in a residential setting. Although research indicates that meditation training can positively influence physical and mental health outcomes, the biological consequences of meditation retreat interventions are relatively understudied. In this study, we examined the influence of a month-long, silent meditation retreat on the expression of genes involved in epigenetic modulation and immune processes. Method: We assessed gene expression changes in experienced meditators attending a month-long Insight meditation retreat (n = 28), as compared to a community control group (n = 34) of experienced practitioners living their everyday lives. Blood samples were collected on day two of the retreat (Time 1) and again 3 weeks later (Time 2). Control participants were also assessed across a 3-week interval, during which they maintained their regular daily routines. Results: As compared to controls, retreat participants showed differential changes in the expression of several genes involved in chromatin modulation and inflammation. The most substantive finding was downregulation of the TNF pathway in retreat participants, which was not observed in controls. Conclusions: These findings indicate that meditation retreat participation may influence some of the inflammatory mechanisms involved in the development of chronic diseases, and that this style of psychosocial intervention may have therapeutic potential, particularly in experienced practitioners.

14.
Appl Ergon ; 99: 103643, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34781180

RESUMEN

Ecological Interface Design (EID) is a framework for developing dynamic interfaces that support operators to understand and take appropriate actions within highly-complex systems. This two-part study involved the development and evaluation of a novel EID-based static aviation risk management display. A within-subjects survey-based experiment employed measures of decision accuracy, situation awareness, user workload, usability, and user perceptions. Results from 23 participants showed that when compared to a risk interface utilised by a large aviation company, the EID display achieved higher usability and lower workload ratings with large effect sizes, with no differences in decision accuracy and situation awareness. The findings provide evidence that the EID framework can improve upon static traditional displays. Research contributions also include a novel model of an aviation ground operations system and an example application of EID to the development of a static display. Further research is necessary to identify the extent of the applications and benefits to static displays.


Asunto(s)
Aviación , Interfaz Usuario-Computador , Concienciación , Humanos , Gestión de Riesgos
15.
Hum Brain Mapp ; 42(10): 3228-3252, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33783922

RESUMEN

Meditation practice is believed to foster states of mindful awareness and mental quiescence in everyday life. If so, then the cultivation of these qualities with training ought to leave its imprint on the activity of intrinsic functional brain networks. In an intensive longitudinal study, we investigated associations between meditation practitioners' experiences of felt mindful awareness and changes in the spontaneous electrophysiological dynamics of functional brain networks. Experienced meditators were randomly assigned to complete 3 months of full-time training in focused-attention meditation (during an initial intervention) or to serve as waiting-list controls and receive training second (during a later intervention). We collected broadband electroencephalogram (EEG) during rest at the beginning, middle, and end of the two training periods. Using a data-driven approach, we segmented the EEG into a time series of transient microstate intervals based on clustering of topographic voltage patterns. Participants also provided daily reports of felt mindful awareness and mental quiescence, and reported daily on four experiential qualities of their meditation practice during training. We found that meditation training led to increases in mindful qualities of awareness, which corroborate contemplative accounts of deepening mental calm and attentional focus. We also observed reductions in the strength and duration of EEG microstates across both interventions. Importantly, changes in the dynamic sequencing of microstates were associated with daily increases in felt attentiveness and serenity during training. Our results connect shifts in subjective qualities of meditative experience with the large-scale dynamics of whole brain functional EEG networks at rest.


Asunto(s)
Concienciación/fisiología , Corteza Cerebral/fisiología , Electroencefalografía/métodos , Meditación , Red Nerviosa/fisiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
16.
Brain Behav Immun ; 89: 256-267, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32640286

RESUMEN

Prior work has linked meditation practice to improvements in interference control. However, the mechanisms underlying these improvements are relatively unknown. In the context of meditation training, improvements in interference control could result eitherfrom increases in controlled attention to goal-relevant stimuli, or from reductions in automatic capture by goal-irrelevant stimuli. Moreover, few studies have linked training-related changes in attention to physiological processes, such as inflammatory activity, that are thought to influence cognitive function. This study addresses these gaps by examining associations between cognitive performance and cytokines in the context of an intensive meditation retreat. Participants were randomly assigned to complete 3 months of meditation training first, or to serve as waitlist controls. The waitlist-control participants then later completed a separate 3-month training intervention. We assessed participants' interference control with a flanker task and used computational modeling to derive component processes of controlled and automatic attention. We also collected blood samples at the beginning, middle, and end of training to quantify changes in cytokine activity. Participants who completed training evidenced better controlled attention than waitlist controls during the first retreat intervention, and controls showed significant improvements in controlled attention when they completed their own, second retreat. Importantly, inflammatory activity was inversely associated with controlled attention during both interventions. Our results suggest that practice of concentration meditation influences interference control by enhancing controlled attention to goal-relevant task elements, and that inflammatory activity relates to individual differences in controlled attention.


Asunto(s)
Meditación , Humanos
17.
Environ Sci Process Impacts ; 22(7): 1461-1474, 2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32558863

RESUMEN

With an ongoing interest in displacing petroleum-based sources of energy with biofuels, there is a need to measure and model the formation and composition of secondary organic aerosol (SOA) from organic compounds present in biofuels. We performed chamber experiments to study SOA formation from four recently identified biofuel molecules and mixtures and commercial gasoline under high NOx conditions: diisobutylene, cyclopentanone, an alkylfuran mixture, and an ethanol-to-hydrocarbon (ETH) mixture. Cyclopentanone and diisobutylene had a significantly lower potential to form SOA compared to commercial gasoline, with SOA mass yields lower than or equal to 0.2%. The alkylfuran mixture had an SOA mass yield (1.6%) roughly equal to that of gasoline (2.0%) but ETH had an average SOA mass yield (11.5%) that was six times higher than that of gasoline. We used a state-of-the-science model to parameterize or simulate the SOA formation in the chamber experiments while accounting for the influence of vapor wall losses. Simulations performed with vapor wall losses turned off and at atmospherically relevant conditions showed that the SOA mass yields were higher than those measured in the chamber at the same photochemical exposure and were also higher than those estimated using a volatility basis set that was fit to the chamber data. The modeled SOA mass yields were higher primarily because they were corrected for vapor wall losses to the Teflon® chamber.


Asunto(s)
Aerosoles , Contaminantes Atmosféricos , Gasolina , Biocombustibles , Gases , Compuestos Orgánicos
18.
Neuroimage ; 211: 116631, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32062082

RESUMEN

Microstates reflect transient brain states resulting from the synchronous activity of brain networks that predominate in the broadband EEG. There has been increasing interest in how the functional organization of the brain varies across individuals, or the extent to which its spatiotemporal dynamics are state dependent. However, little research has examined within and between-person correlates of microstate temporal parameters in healthy populations. In the present study, neuroelectric activity recorded during eyes-closed rest and during simple visual fixation was segmented into a time series of transient microstate intervals. It was found that five data-driven microstate configurations explained the preponderance of topographic variance in the EEG time series of the 374 recordings (from 187 participants) included in the study. We observed that the temporal dynamics of microstates varied within individuals to a greater degree than they differed between persons, with within-person factors explaining a large portion of the variance in mean microstate duration and occurrence rate. Nevertheless, several individual differences were found to predict the temporal dynamics of microstates. Of these, age and gender were the most reliable. These findings not only suggest that the rich temporal dynamics of whole-brain neuronal networks vary considerably within individuals, but that microstates appear to differentiate persons based on trait individual differences. Rather than focusing exclusively on between-person differences in microstates as measures of brain function, researchers should turn their attention towards understanding the factors contributing to within-person variation.


Asunto(s)
Afecto/fisiología , Envejecimiento/fisiología , Atención/fisiología , Corteza Cerebral/fisiología , Electroencefalografía , Neuroimagen Funcional , Personalidad/fisiología , Desempeño Psicomotor/fisiología , Adulto , Anciano , Femenino , Humanos , Individualidad , Masculino , Cadenas de Markov , Persona de Mediana Edad , Adulto Joven
20.
J Cogn Neurosci ; 31(8): 1184-1204, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31059348

RESUMEN

The ability to discriminate among goal-relevant stimuli tends to diminish when detections must be made continuously over time. Previously, we reported that intensive training in shamatha (focused-attention) meditation can improve perceptual discrimination of difficult-to-detect visual stimuli [MacLean, K. A., Ferrer, E., Aichele, S. R., Bridwell, D. A., Zanesco, A. P., Jacobs, T. L., et al. Intensive meditation training improves perceptual discrimination and sustained attention. Psychological Science, 21, 829-839, 2010]. Here we extend these findings to examine how discrimination difficulty and meditation training interact to modulate event-related potentials of attention and perceptual processing during vigilance. Training and wait-list participants completed a continuous performance task at the beginning, middle, and end of two 3-month meditation interventions. In the first intervention (Retreat 1), the continuous performance task target was adjusted across assessments to match training-related changes in participants' perceptual capacity. In the second intervention (Retreat 2), the target was held constant across training, irrespective of changes in discrimination capacity. No training effects were observed in Retreat 1, whereas Retreat 2 was associated with changes in the onset of early sensory signals and an attenuation of within-task decrements at early latencies. In addition, changes at later stimulus processing stages were directly correlated with improvements in perceptual threshold across the second intervention. Overall, these findings demonstrate that improvements in perceptual discrimination can modulate electrophysiological markers of perceptual processing and attentional control during sustained attention, but likely only under conditions where an individual's discrimination capacity is allowed to exceed the demand imposed by the difficulty of a visual target. These results contribute to basic understanding of the dependence of perceptual processing and attentional control to contextual demands and their susceptibility to directed mental training.


Asunto(s)
Atención/fisiología , Discriminación en Psicología/fisiología , Potenciales Evocados/fisiología , Meditación , Práctica Psicológica , Desempeño Psicomotor/fisiología , Percepción Visual/fisiología , Adulto , Anciano , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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