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1.
Psychol Res ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573358

RESUMO

The Autobiographical Interview, a method for evaluating detailed memory of real-world events, reliably detects differences in episodic specificity at retrieval between young and older adults in the laboratory. Whether this age-associated reduction in episodic specificity for autobiographical event retrieval is present outside of the laboratory remains poorly understood. We used a videoconference format to administer the Autobiographical Interview to cognitively unimpaired older adults (N = 49, M = 69.5, SD = 5.94) and young adults (N = 54, M = 22.5, SD = 4.19) who were in their homes at the time of retrieval. Relative to young adults, older adults showed reduced episodic specificity in their home environment, as reflected by fewer episodic or "internal" details (t (101) = 3.23, p = 0.009) and more "external" details (i.e., semantic, language-based details) (t (101) = 3.60, p = 0.003). These findings, along with detail subtype profiles in the narratives, bolster the ecological validity of the Autobiographical Interview and add promise to the use of virtual cognitive testing to improve the accessibility, participant diversity, scalability, and ecological validity of memory research.

2.
Cogn Emot ; : 1-11, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38628081

RESUMO

This study used ratings and event-related potentials (ERPs) to compare the mechanisms through which verbal irony and cognitive reappraisal mitigate negative emotion. Verbal irony is when the literal meaning of words contrasts with their intended meaning. Cognitive reappraisal is when we reconsider emotional stimuli to make them less intense. Our hypothesis was that cognitive reappraisal is a potential mechanism through which irony reduces negative emotion. Participants viewed mildly negative pictures first, then read an ironic or literal statement about it in one block, and used cognitive reappraisal of or attending to the picture in the other block. Participants then viewed the picture for a second time, before rating how negative they felt. Behaviourally, irony reduced negative feelings more than literal statements, and reappraisal reduced negative feelings more than attending, with a larger reduction from reappraisal than from irony. In ERPs, irony elicited a prolonged N400 compared to literal, indexing an initial contrast between picture and word affect and sustained processing of their combination. Cognitive reappraisal elicited a larger late positivity compared to attending at the instruction screen. No differences were found during second picture presentation. These findings suggest that irony and cognitive reappraisal can reduce negative affect in different ways.

3.
Hum Brain Mapp ; 44(1): 245-257, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36087094

RESUMO

Clinical theories of adaptation in bereavement highlight a need for flexible shifting between mental states. However, prolonged motivational salience of the deceased partner may be a complicating factor, particularly when coupled with perseverative thinking about the loss. We investigated how prolonged grief symptoms might relate to resting state functional brain network connectivity in a sample of older adults (n = 38) who experienced the death of a partner 6-36 months prior, and whether intranasal oxytocin (as a neuropeptide involved in pair-bonding) had differential effects in participants with higher prolonged grief symptoms. Higher scores on the Inventory of Complicated Grief (ICG) were associated with lower anticorrelation (i.e., higher functional connectivity) between the defaultretrosplenial - cingulo-operculardACC network pair. Intranasal oxytocin increased functional connectivity in the same defaultretrosplenial - cingulo-operculardACC circuit but ICG scores did not moderate effects of oxytocin, contrary to our prediction. Higher ICG scores were associated with longer dwell time in a dynamic functional connectivity state featuring positive correlations among default, frontoparietal, and cingulo-opercular networks, across both placebo and oxytocin sessions. Dwell time was not significantly affected by oxytocin, and higher prolonged grief symptoms were not associated with more variability in dynamic functional connectivity states over the scan. Results offer preliminary evidence that prolonged grief symptoms in older adults are associated with patterns of static and time-varying functional network connectivity and may specifically involve a default network-salience-related circuit that is sensitive to oxytocin.


Assuntos
Luto , Ocitocina , Idoso , Humanos , Encéfalo/diagnóstico por imagem , Cognição , Pesar , Imageamento por Ressonância Magnética , Ocitocina/farmacologia
4.
Hum Brain Mapp ; 43(2): 773-786, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34652882

RESUMO

Many individuals spend a significant amount of their time "mind-wandering". Mind-wandering often includes spontaneous, nonintentional thought, and a neural correlate of this kind of thought is the default mode network (DMN). Thoughts during mind-wandering can have positive or negative valence, but only little is known about the neural correlates of positive or negative thoughts. We used resting-state functional magnetic resonance imaging (fMRI) and music to evoke mind-wandering in n = 33 participants, with positive-sounding music eliciting thoughts with more positive valence and negative-sounding music eliciting thoughts with more negative valence. Applying purely data-driven analysis methods, we show that medial orbitofrontal cortex (mOFC, part of the ventromedial prefrontal cortex) and the posterior cingulate sulcus (likely area 23c of the posterior cingulate cortex), two sub-regions of the DMN, modulate the valence of thought-contents during mind-wandering. In addition, across two independent experiments, we observed that the posterior cingulate sulcus, a region involved in pain, shows valence-specific functional connectivity with core regions of the brain's putative pain network. Our results suggest that two DMN regions (mOFC and posterior cingulate sulcus) support the formation of negative spontaneous, nonintentional thoughts, and that the interplay between these structures with regions of the putative pain network forms a neural mechanism by which thoughts can become painful.


Assuntos
Percepção Auditiva/fisiologia , Conectoma , Rede de Modo Padrão/fisiologia , Emoções/fisiologia , Giro do Cíngulo/fisiologia , Música , Rede Nervosa/fisiologia , Dor/fisiopatologia , Córtex Pré-Frontal/fisiologia , Pensamento/fisiologia , Adulto , Rede de Modo Padrão/diagnóstico por imagem , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Dor/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
5.
Cogn Affect Behav Neurosci ; 22(6): 1334-1348, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35896854

RESUMO

Connectivity of the brain at rest can reflect individual differences and impact behavioral outcomes, including memory. The present study investigated how culture influences functional connectivity with regions of the medial temporal lobe. In this study, 46 Americans and 59 East Asians completed a resting state scan after encoding pictures of objects. To investigate cross-cultural differences in resting state functional connectivity, left parahippocampal gyrus (anterior and posterior regions) and left hippocampus were selected as seed regions. These regions were selected, because they were previously implicated in a study of cultural differences during the successful encoding of detailed memories. Results revealed that left posterior parahippocampal gyrus had stronger connectivity with temporo-occipital regions for East Asians compared with Americans and stronger connectivity with parieto-occipital regions for Americans compared with East Asians. Left anterior parahippocampal gyrus had stronger connectivity with temporal regions for East Asians than Americans and stronger connectivity with frontal regions for Americans than East Asians. Although connectivity did not relate to memory performance, patterns did relate to cultural values. The degree of independent self-construal and subjective value of tradition were associated with functional connectivity involving left anterior parahippocampal gyrus. Findings are discussed in terms of potential cultural differences in memory consolidation or more general trait or state-based processes, such as holistic versus analytic processing.


Assuntos
Imageamento por Ressonância Magnética , Lobo Temporal , Humanos , Imageamento por Ressonância Magnética/métodos , Lobo Temporal/diagnóstico por imagem , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Hipocampo
6.
Psychol Res ; 86(4): 1203-1214, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34165612

RESUMO

COVID-19 has led to mental health adversities worldwide. The current study examined whether daily practice of brief mindfulness training has a beneficial impact on affective well-being, and mitigates the negative impact of exposure to COVID-19 news during the pandemic. Participants were randomly assigned into a mindfulness training (MT) group or a waitlist control (WC) group. Participants in the MT group practiced guided mindfulness meditation for a minimum of 10 min each day for 10 days. Both groups completed questionnaires assessing well-being at baseline and after the 10-day period. We also included four ecological momentary assessments (EMA) interspersed throughout the day to measure fine-grained affective states and recent exposure to COVID-19-related news, which has been linked to negative affect. We observed an increase in positive affect in the MT group compared to the WC group in the post-training assessment. However, no group differences emerged in the other three post-training affective measures of negative affect, anxiety and depression. EMA revealed that the MT group also showed more positive affective valence than the WC group across the 10 days. Notably, the WC group reported more negative affective valence following COVID-19 news exposure, whereas the MT group was not impacted. Taken together, our study indicates brief sessions of guided mindfulness meditation during COVID-19 may boost positive affect and serve as a protective buffer against the negative impact of exposure to COVID-19-related news on affective well-being. These findings highlight the utility of mindfulness meditation as an accessible and cost-effective technique to elevate positive affect amidst the COVID-19 pandemic.


Assuntos
COVID-19 , Meditação , Atenção Plena , Ansiedade/terapia , COVID-19/epidemiologia , Humanos , Meditação/psicologia , Atenção Plena/métodos , Pandemias
7.
Proc Natl Acad Sci U S A ; 116(8): 3316-3321, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30718430

RESUMO

Mind wandering represents the human capacity for internally focused thought and relies upon the brain's default network and its interactions with attentional networks. Studies have characterized mind wandering in healthy people, yet there is limited understanding of how this capacity is affected in clinical populations. This paper used a validated thought-sampling task to probe mind wandering capacity in two neurodegenerative disorders: behavioral variant frontotemporal dementia [(bvFTD); n = 35] and Alzheimer's disease [(AD); n = 24], compared with older controls (n = 37). These patient groups were selected due to canonical structural and functional changes across sites of the default and frontoparietal networks and well-defined impairments in cognitive processes that support mind wandering. Relative to the controls, bvFTD patients displayed significantly reduced mind wandering capacity, offset by a significant increase in stimulus-bound thought. In contrast, AD patients demonstrated comparable levels of mind wandering to controls, in the context of a relatively subtle shift toward stimulus-/task-related forms of thought. In the patient groups, mind wandering was associated with gray matter integrity in the hippocampus/parahippocampus, striatum, insula, and orbitofrontal cortex. Resting-state functional connectivity revealed associations between mind wandering capacity and connectivity within and between regions of the frontoparietal and default networks with distinct patterns evident in patients vs. controls. These findings support a relationship between altered mind wandering capacity in neurodegenerative disorders and structural and functional integrity of the default and frontoparietal networks. This paper highlights a dimension of cognitive dysfunction not well documented in neurodegenerative disorders and validates current models of mind wandering in a clinical population.


Assuntos
Doença de Alzheimer/fisiopatologia , Atrofia/fisiopatologia , Encefalopatias/fisiopatologia , Hipocampo/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Atrofia/diagnóstico por imagem , Atenção/fisiologia , Encefalopatias/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Demência Frontotemporal/diagnóstico por imagem , Demência Frontotemporal/fisiopatologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/fisiopatologia , Hipocampo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Degeneração Neural/diagnóstico por imagem , Degeneração Neural/fisiopatologia , Rede Nervosa/fisiologia , Vias Neurais/fisiologia , Descanso/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia
8.
Nat Rev Neurosci ; 17(11): 718-731, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27654862

RESUMO

Most research on mind-wandering has characterized it as a mental state with contents that are task unrelated or stimulus independent. However, the dynamics of mind-wandering - how mental states change over time - have remained largely neglected. Here, we introduce a dynamic framework for understanding mind-wandering and its relationship to the recruitment of large-scale brain networks. We propose that mind-wandering is best understood as a member of a family of spontaneous-thought phenomena that also includes creative thought and dreaming. This dynamic framework can shed new light on mental disorders that are marked by alterations in spontaneous thought, including depression, anxiety and attention deficit hyperactivity disorder.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Fantasia , Transtornos Mentais/fisiopatologia , Rede Nervosa/fisiologia , Pensamento/fisiologia , Animais , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Transtornos Mentais/diagnóstico por imagem , Transtornos Mentais/psicologia , Rede Nervosa/diagnóstico por imagem
9.
Mem Cognit ; 49(3): 422-437, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32965620

RESUMO

Episodic autobiographical memories (EAMs) can come to mind through two retrieval routes, one direct (i.e., an EAM is retrieved almost instantaneously) and the other generative (i.e., by using autobiographical/general knowledge to cue an EAM). It is well established that normal cognitive aging is associated with a reduction in the retrieval of EAMs, but the contributions of direct or generative reconstruction to the age-related shift toward general memories remain unknown. Prior studies also have not clarified whether similar cognitive mechanisms facilitate the ability to successfully reconstruct EAMs and elaborate them in event-specific detail. To address these gaps in knowledge, young and older participants were asked to reconstruct EAMs using a "think-aloud" paradigm and then describe in detail a subset of retrieved memories. An adapted scoring procedure was implemented to categorize memories accessed during reconstruction, and the Autobiographical Interview (AI) scoring procedure was utilized for elaboration scoring. Results indicated that in comparison with young adults, older adults not only engaged in direct retrieval less often than young adults but they also more often ended generative retrieval at general events instead of EAMs. The ability to elaborate EAMs with internal details was positively associated with the ability to use generative retrieval to reconstruct EAMs in both young and older adults, but there was no relationship between internal detail elaboration and direct retrieval in either age group. Taken together, these results indicate age-related differences in direct and generative retrieval contribute to overgeneral autobiographical memory and they support a connection between generative retrieval and elaboration.


Assuntos
Memória Episódica , Idoso , Humanos , Rememoração Mental
10.
Cogn Emot ; 35(2): 269-281, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33076778

RESUMO

Although task-unrelated thinking (often conceptualised as "mind-wandering") has been increasingly investigated in recent years, the content and correlates of everyday off-task thought in clinical disorders, particularly anxiety disorders, remain poorly understood. We aimed to address this gap by using ecological momentary assessment to assess off-task and on-task thoughts in adults with social anxiety disorder (SAD) and demographically matched controls. Findings showed that individuals with SAD more frequently engaged in internally oriented off-task thinking than healthy controls, but not externally oriented off-task thinking. Compared to thoughts focused on the task at hand, adults with SAD rated their internal off-task thoughts as less controllable, more self-focused, and as associated with worse mood than controls. However, when the SAD group was focused on the task at hand, group differences disappeared. Daily findings were paralleled by higher scores in SAD on a trait measure of unintentional, but not intentional, mind-wandering. In sum, the content and mood correlate of internally oriented off-task thoughts depended on the presence of clinical anxiety. In addition, focusing on the task at hand normalised thought content and mood in SAD, highlighting a window for intervention.


Assuntos
Fobia Social , Adulto , Cognição , Avaliação Momentânea Ecológica , Humanos
11.
Conscious Cogn ; 85: 103023, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32979619

RESUMO

In young adults, valence not only alters the degree to which future events are imagined in rich episodic detail, but also how memorable these events are later on. For older adults, how valence influences episodic detail generation while imagining future events, or recalling these details at another time, remains unclear. We investigated the effect of valence on the specificity and memorability of episodic future thinking (EFT) in young and older adults. Among young and older adults, negative EFT was accompanied by less episodic detail generation relative to positive and neutral EFT. A similar reduction in episodic specificity for negative EFT was found two days later when participants recalled their previously imagined events. Notably, while older adults generated less episodically specific future thoughts relative to young adults, age did not influence the effect of valence on episodic detail generation at imagination or recollection.


Assuntos
Memória Episódica , Idoso , Emoções , Previsões , Humanos , Imaginação , Rememoração Mental , Adulto Jovem
12.
Psychol Res ; 83(4): 747-760, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30291418

RESUMO

An intriguing aspect of human cognition is the unique capacity to mentally retreat from our immediate surroundings to consider perspectives distinct from the here and now. Despite increasing interest in this phenomenon, relatively little is known regarding age-related changes in off-task, self-generated thought (often referred to as "mind-wandering"), particularly under conditions of low cognitive demand. While a number of studies have investigated the temporal orientation of mind-wandering with increasing age, findings have been largely inconsistent. Here, we explored the frequency, temporal focus, and self-referential/social content of spontaneous task-unrelated, perceptually decoupled thought in 30 young and 33 healthy older adults using the Shape Expectations task, a validated experimental paradigm in which discrete facets of inner mentation are quantified along a conceptual continuum using open-ended report. Participants also completed the daydreaming subscale of the Imaginal Process Inventory (IPI) as a trait measure of mind-wandering propensity. Significant group differences emerged on the Shape Expectations task, with reduced instances of mind-wandering in the context of elevated task-related thoughts relative to younger adults. In terms of temporal focus, a preponderance of present/atemporal off-task thoughts was evident irrespective of group; however, significantly higher levels of future-oriented thoughts were provided by younger adults, contrasting with significantly higher instances of retrospection in the older group. In addition, older adults displayed significantly fewer incidences of self-referential cognition relative to their younger counterparts. Our findings indicate a distinct attenuation of off-task, self-generated thought processes with increasing age, with evidence for a shift in temporal focus and self-referential quality, during periods of low cognitive demand.


Assuntos
Envelhecimento/fisiologia , Atenção/fisiologia , Cognição/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Austrália , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Neuroimage ; 147: 632-649, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28040543

RESUMO

Anticorrelation between the default network (DN) and dorsal attention network (DAN) is thought to be an intrinsic aspect of functional brain organization reflecting competing functions. However, the effect size of functional connectivity (FC) between the DN and DAN has yet to be established. Furthermore, the stability of anticorrelations across distinct DN subsystems, different contexts, and time, remains unexplored. In study 1 we summarize effect sizes of DN-DAN FC from 20 studies, and in study 2 we probe the variability of DN-DAN interactions across six different cognitive states in a new data set. We show that: (i) the DN and DAN have an independent rather than anticorrelated relationship when global signal regression is not used (median effect size across studies: r=-.06; 95% CI: -.15 to .08); (ii) the DAN exhibits weak negative FC with the DN Core subsystem but is uncorrelated with the dorsomedial prefrontal and medial temporal lobe subsystems; (iii) DN-DAN interactions vary significantly across different cognitive states; (iv) DN-DAN FC fluctuates across time between periods of anticorrelation and periods of positive correlation; and (v) changes across time in the strength of DN-DAN coupling are coordinated with interactions involving the frontoparietal control network (FPCN). Overall, the observed weak effect sizes related to DN-DAN anticorrelation suggest the need to re-conceptualize the nature of interactions between these networks. Furthermore, our findings demonstrate that DN-DAN interactions are not stable, but rather, exhibit substantial variability across time and context, and are coordinated with broader network dynamics involving the FPCN.


Assuntos
Atenção/fisiologia , Córtex Cerebral/fisiologia , Conectoma/métodos , Rede Nervosa/fisiologia , Pensamento/fisiologia , Percepção Visual/fisiologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imaginação/fisiologia , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Descanso
14.
Neuroimage ; 104: 69-78, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25281800

RESUMO

The goal of the present study was to examine relationships between individual differences in resting state functional connectivity as ascertained by fMRI (rs-fcMRI) and performance on tasks of executive function (EF), broadly defined as the ability to regulate thoughts and actions. Unlike most previous research that focused on the relationship between rs-fcMRI and a single behavioral measure of EF, in the current study we examined the relationship of rs-fcMRI with individual differences in subcomponents of EF. Ninety-one adults completed a resting state fMRI scan and three separate EF tasks outside the magnet: inhibition of prepotent responses, task set shifting, and working memory updating. From these three measures, we derived estimates of common aspects of EF, as well as abilities specific to working memory updating and task shifting. Using Independent Components Analysis (ICA), we identified across the group of participants several networks of regions (Resting State Networks, RSNs) with temporally correlated time courses. We then used dual regression to explore how these RSNs covaried with individual differences in EF. Dual regression revealed that increased higher common EF was associated with connectivity of a) frontal pole with an attentional RSN, and b) Crus I and II of the cerebellum with the right frontoparietal RSN. Moreover, higher shifting-specific abilities were associated with increased connectivity of angular gyrus with a ventral attention RSN. The results of the current study suggest that the organization of the brain at rest may have important implications for individual differences in EF, and that individuals higher in EF may have expanded resting state networks as compared to individuals with lower EF.


Assuntos
Função Executiva/fisiologia , Individualidade , Rede Nervosa/fisiologia , Adolescente , Adulto , Cerebelo/anatomia & histologia , Cerebelo/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo/fisiologia , Valor Preditivo dos Testes , Análise de Componente Principal , Desempenho Psicomotor/fisiologia , Movimentos Sacádicos/fisiologia , Adulto Jovem
15.
Neuroimage ; 111: 611-21, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25725466

RESUMO

The neural basis and cognitive functions of various spontaneous thought processes, particularly mind-wandering, are increasingly being investigated. Although strong links have been drawn between the occurrence of spontaneous thought processes and activation in brain regions comprising the default mode network (DMN), spontaneous thought also appears to recruit other, non-DMN regions just as consistently. Here we present the first quantitative meta-analysis of neuroimaging studies of spontaneous thought and mind-wandering in order to address the question of their neural correlates. Examining 24 functional neuroimaging studies of spontaneous thought processes, we conducted a meta-analysis using activation likelihood estimation (ALE). A number of key DMN areas showed consistent recruitment across studies, including medial prefrontal cortex, posterior cingulate cortex, medial temporal lobe, and bilateral inferior parietal lobule. Numerous non-DMN regions, however, were also consistently recruited, including rostrolateral prefrontal cortex, dorsal anterior cingulate cortex, insula, temporopolar cortex, secondary somatosensory cortex, and lingual gyrus. These meta-analytic results indicate that DMN activation alone is insufficient to adequately capture the neural basis of spontaneous thought; frontoparietal control network areas, and other non-DMN regions, appear to be equally central. We conclude that further progress in the cognitive and clinical neuroscience of spontaneous thought will therefore require a re-balancing of our view of the contributions of various regions and networks throughout the brain, and beyond the DMN.


Assuntos
Encéfalo/fisiologia , Função Executiva/fisiologia , Neuroimagem Funcional , Rede Nervosa/fisiologia , Pensamento/fisiologia , Humanos
16.
Brain Cogn ; 93: 1-10, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25463243

RESUMO

Self-generated cognition, or mind wandering, refers to the quintessentially human tendency to withdraw from the immediate external environment and engage in internally driven mentation. This thought activity is suggested to be underpinned by a distributed set of regions in the brain, referred to as the default network. To date, experimental assessment of mind wandering has typically taken place during performance of a concurrent attention-demanding task. The attentional demands of concurrent tasks can influence the emergence of mind wandering, and their application to clinical disorders with reduced cognitive resources is limited. Furthermore, few paradigms have investigated the phenomenological content of mind wandering episodes. Here, we present data from a novel thought sampling task that measures both the frequency and qualitative content of mind wandering, in the absence of a concurrent task to reduce cognitive demand. The task was validated in a non-pathological cohort of 31 older controls and resting-state functional connectivity analyses in a subset of participants (n=18) was conducted to explore the neural bases of mind wandering. Overall, instances of mind wandering were found to occur in 37% of experimental trials. Resting state functional connectivity analyses confirmed that mind wandering frequency was associated with regional patterns of both increased and decreased default network connectivity, namely in the temporal lobe, posterior cingulate cortex and dorsal medial prefrontal cortex. Our findings demonstrate that the novel task provides a context of low cognitive demand, which is conducive to mind wandering. Furthermore, performance on the task is associated with specific patterns of functional connectivity in the default network. Together, this new paradigm offers an important avenue to investigate the frequency and content of mind wandering in the context of low cognitive demands, and has significant potential to be applied in clinical conditions with reduced cognitive resources.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Cognição/fisiologia , Rede Nervosa/fisiologia , Pensamento/fisiologia , Idoso , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Lobo Temporal/fisiologia
17.
Neuroimage ; 91: 324-35, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24486981

RESUMO

A growing number of studies suggest the brain's "default network" becomes engaged when individuals recall their personal past or simulate their future. Recent reports of heterogeneity within the network raise the possibility that these autobiographical processes comprised of multiple component processes, each supported by distinct functional-anatomic subsystems. We previously hypothesized that a medial temporal subsystem contributes to autobiographical memory and future thought by enabling individuals to retrieve prior information and bind this information into a mental scene. Conversely, a dorsal medial subsystem was proposed to support social-reflective aspects of autobiographical thought, allowing individuals to reflect on the mental states of one's self and others (i.e. "mentalizing"). To test these hypotheses, we first examined activity in the default network subsystems as participants performed two commonly employed tasks of episodic retrieval and mentalizing. In a subset of participants, relationships among task-evoked regions were examined at rest, in the absence of an overt task. Finally, large-scale fMRI meta-analyses were conducted to identify brain regions that most strongly predicted the presence of episodic retrieval and mentalizing, and these results were compared to meta-analyses of autobiographical tasks. Across studies, laboratory-based episodic retrieval tasks were preferentially linked to the medial temporal subsystem, while mentalizing tasks were preferentially linked to the dorsal medial subsystem. In turn, autobiographical tasks engaged aspects of both subsystems. These results suggest the default network is a heterogeneous brain system whose subsystems support distinct component processes of autobiographical thought.


Assuntos
Encéfalo/fisiologia , Memória Episódica , Rememoração Mental/fisiologia , Teoria da Mente/fisiologia , Adulto , Algoritmos , Simulação por Computador , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Método de Monte Carlo , Oxigênio/sangue , Desempenho Psicomotor/fisiologia , Reconhecimento Psicológico/fisiologia , Repressão Psicológica , Descanso/fisiologia , Software , Adulto Jovem
18.
J Neuropsychol ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949213

RESUMO

Recent research suggests that the retrieval of autobiographical memories among cognitively healthy middle-aged and older adults is sensitive to the Apolipoprotein E ε4 (APOE4) allele, a genetic marker that increases the risk of Alzheimer's disease (AD) dementia. However, whether the APOE4-associated alteration in autobiographical memory retrieval encompasses rapid (i.e. direct retrieval) or iterative (i.e. generative retrieval) processes remains unclear. In the present study, 39 APOE4 carriers and 45 non-carriers (ages 60-80) who scored within normal limits on neuropsychological testing were cued to generate specific autobiographical events. We examined group differences in direct and generative retrieval and correlated direct and generative retrieval rates with performance on neuropsychological tests. Direct retrieval rates were lower in the APOE4 carriers compared to non-carriers. Episodic memory positively correlated with direct retrieval rates across the sample, though this relationship became non-significant when factoring in age and sex. There were no significant findings related to successful generative retrieval rates and its efficiency. In summary, compared to non-carriers, cognitively unimpaired middle-aged to older adult APOE4 carriers demonstrated greater difficulty, rapidly reconstructing specific autobiographical events without the support of semantic memory, suggesting that early autobiographical memory retrieval processes demonstrate vulnerability to AD-related risk factors.

19.
Psychol Bull ; 150(5): 621-641, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38619477

RESUMO

There is a growing recognition that thoughts often arise independently of external demands. These thoughts can span from reminiscing your last vacation to contemplating career goals to fantasizing about meeting your favorite musician. Often referred to as mind wandering, such frequently occurring unprompted thoughts have widespread impact on our daily functions, with the dominant narrative converging on a negative relationship between unprompted thought and affective well-being. In this systematic review of 76 studies, we implemented a meta-analysis and qualitative review to elucidate if and when unprompted thought is indeed negatively associated with affective well-being in adults. Using a multilevel mixed-model approach on 386 effect sizes from 23,168 participants across 64 studies, our meta-analyses indicated an overall relationship between unprompted thought and worse affective well-being (r¯ = -.18, 95% CI [-.23, -.14]); however, the magnitude and direction of this relationship changed when considering specific aspects of the phenomenon (including thought content and intentionality) and methodological approaches (including questionnaires vs. experience sampling). The qualitative review further contextualizes this relationship by revealing the nuances of how and when unprompted thought is associated with affective well-being. Taken together, our meta-analysis and qualitative review indicate that the commonly reported relationship between unprompted thought and affective well-being is contingent upon the content and conceptualization of unprompted thought, as well as the methodological and analytic approaches implemented. Based on these findings, we propose emerging directions for future empirical and theoretical work that highlight the importance of accounting for when, how, and for whom unprompted thought is associated with affective well-being. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Afeto , Pensamento , Humanos , Pensamento/fisiologia , Afeto/fisiologia , Satisfação Pessoal , Adulto
20.
Eur Neuropsychopharmacol ; 82: 72-81, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503084

RESUMO

Mindfulness-based cognitive therapy (MBCT) stands out as a promising augmentation psychological therapy for patients with obsessive-compulsive disorder (OCD). To identify potential predictive and response biomarkers, this study examines the relationship between clinical domains and resting-state network connectivity in OCD patients undergoing a 3-month MBCT programme. Twelve OCD patients underwent two resting-state functional magnetic resonance imaging sessions at baseline and after the MBCT programme. We assessed four clinical domains: positive affect, negative affect, anxiety sensitivity, and rumination. Independent component analysis characterised resting-state networks (RSNs), and multiple regression analyses evaluated brain-clinical associations. At baseline, distinct network connectivity patterns were found for each clinical domain: parietal-subcortical, lateral prefrontal, medial prefrontal, and frontal-occipital. Predictive and response biomarkers revealed significant brain-clinical associations within two main RSNs: the ventral default mode network (vDMN) and the frontostriatal network (FSN). Key brain nodes -the precuneus and the frontopolar cortex- were identified within these networks. MBCT may modulate vDMN and FSN connectivity in OCD patients, possibly reducing symptoms across clinical domains. Each clinical domain had a unique baseline brain connectivity pattern, suggesting potential symptom-based biomarkers. Using these RSNs as predictors could enable personalised treatments and the identification of patients who would benefit most from MBCT.


Assuntos
Imageamento por Ressonância Magnética , Atenção Plena , Transtorno Obsessivo-Compulsivo , Humanos , Transtorno Obsessivo-Compulsivo/terapia , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/fisiopatologia , Masculino , Feminino , Adulto , Atenção Plena/métodos , Descanso/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Adulto Jovem , Pessoa de Meia-Idade , Terapia Cognitivo-Comportamental/métodos , Rede de Modo Padrão/diagnóstico por imagem , Rede de Modo Padrão/fisiopatologia , Resultado do Tratamento , Vias Neurais/fisiopatologia , Vias Neurais/diagnóstico por imagem
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