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1.
J Neurosci ; 44(32)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39009438

RESUMO

Neuroticism/negative emotionality (N/NE)-the tendency to experience anxiety, fear, and other negative emotions-is a fundamental dimension of temperament with profound consequences for health, wealth, and well-being. Elevated N/NE is associated with a panoply of adverse outcomes, from reduced socioeconomic attainment to psychiatric illness. Animal research suggests that N/NE reflects heightened reactivity to uncertain threat in the bed nucleus of the stria terminalis (BST) and central nucleus of the amygdala (Ce), but the relevance of these discoveries to humans has remained unclear. Here we used a novel combination of psychometric, psychophysiological, and neuroimaging approaches to test this hypothesis in an ethnoracially diverse, sex-balanced sample of 220 emerging adults selectively recruited to encompass a broad spectrum of N/NE. Cross-validated robust-regression analyses demonstrated that N/NE is preferentially associated with heightened BST activation during the uncertain anticipation of a genuinely distressing threat (aversive multimodal stimulation), whereas N/NE was unrelated to BST activation during certain-threat anticipation, Ce activation during either type of threat anticipation, or BST/Ce reactivity to threat-related faces. It is often assumed that different threat paradigms are interchangeable assays of individual differences in brain function, yet this has rarely been tested. Our results revealed negligible associations between BST/Ce reactivity to the anticipation of threat and the presentation of threat-related faces, indicating that the two tasks are nonfungible. These observations provide a framework for conceptualizing emotional traits and disorders; for guiding the design and interpretation of biobank and other neuroimaging studies of psychiatric risk, disease, and treatment; and for refining mechanistic research.


Assuntos
Tonsila do Cerebelo , Emoções , Imageamento por Ressonância Magnética , Neuroticismo , Núcleos Septais , Núcleos Septais/fisiologia , Núcleos Septais/diagnóstico por imagem , Humanos , Masculino , Feminino , Tonsila do Cerebelo/fisiologia , Tonsila do Cerebelo/diagnóstico por imagem , Adulto Jovem , Neuroticismo/fisiologia , Adulto , Emoções/fisiologia , Incerteza , Medo/fisiologia , Medo/psicologia , Adolescente
2.
Thorax ; 79(4): 340-348, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38129116

RESUMO

OBJECTIVE: The objective of this study is to compare the effectiveness of lower limb low-load blood flow restriction training (LL-BFRT) with high-load strength training (HL-ST) as part of an outpatient pulmonary rehabilitation programme on leg strength in patients with chronic obstructive pulmonary disease (COPD). METHODS: Participants were randomised to LL-BFRT or HL-ST (24 sessions). LL-BFRT was done at 30% 1-repetition maximum (1-RM) with 70% arterial occlusion pressure. HL-ST was done at 70% 1-RM. Primary outcome was isometric strength of knee extensors and flexors. Secondary outcomes were 1-RM, functional exercise capacity, physical activity, symptom burden and health-related quality of life. Perceptions of dyspnoea and leg fatigue were recorded after every exercise. We compared groups with t-tests. RESULTS: We included 30 participants (13 women, 17 men, 64 (9) years, forced expiratory volume in 1 s 47 (18)% pred.), 24 completed the study. Isometric knee extensor strength improved to a clinically relevant degree in both legs in both groups (LL-BFRT: right leg 9 (20) Nm, left leg 10 (18) Nm; HL-ST: right leg 15 (26) Nm, left leg 16 (30) Nm, data are mean (SD)), without statistically significant or clinically relevant between-group differences (right leg mean difference= -6.4, 95% CI= -13.20 to 25.92 Nm, left leg mean difference= -5.6, 95% CI= -15.44 to 26.55 Nm). 1 min sit-to-stand test performance improved to a clinically relevant degree only in the LL-BFRT group (4 (4) vs 1 (5) repetitions). Interestingly, physical activity improved to a clinically relevant degree only in the LL-BFRT group (1506 (2441) vs -182 (1971) steps/day). LL-BFRT lowered perceived in-exercise dyspnoea and increased leg fatigue compared with HL-ST in the initial 12 trainings. CONCLUSION: In patients with stable COPD undergoing outpatient pulmonary rehabilitation, LL-BFRT was not superior to HL-ST in improving leg strength. LL-BFRT led to similar strength gains as HL-ST while reducing perceptions of dyspnoea in the initial training phase. TRIAL REGISTRATION NUMBER: NCT04151771.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Treinamento Resistido , Masculino , Humanos , Feminino , Projetos Piloto , Qualidade de Vida , Terapia de Restrição de Fluxo Sanguíneo , Método Simples-Cego , Doença Pulmonar Obstrutiva Crônica/reabilitação , Dispneia/etiologia , Fadiga , Força Muscular
3.
Sensors (Basel) ; 24(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38931483

RESUMO

The Orthelligent Pro sensor is a practicable, portable measuring instrument. This study assessed the validity and reliability of this sensor in measuring single-leg countermovement jumps. Fifty healthy athletic adults participated in two measurement sessions a week apart in time. They performed single-leg countermovement jumps on the force plate while wearing the Orthelligent Pro sensor on their lower leg. During the first measurement session, Tester 1 invited the participants to make three single-leg countermovement jumps; subsequently, Tester 2 did the same. For assessing the sensor's intratester reliability, Tester 1 again invited the participants to make three single-leg countermovement jumps during the second measurement session. The sensor's validity was assessed by using the force plate results as the gold standard. To determinate the agreement between two measurements, Bland-Altman plots were created. The intertester reliability (ICC = 0.99; 0.97) and intratester reliability (ICC = 0.96; 0.82) were both excellent. The validity calculated (i) on the basis of the mean value of three jumps and (ii) on the basis of the maximum value of three jumps was very high, but it showed a systematic error. Taking this error into account, physiotherapists can use the Orthelligent Pro sensor as a valid and reliable instrument for measuring the jump height of countermovement jumps.


Assuntos
Perna (Membro) , Humanos , Masculino , Adulto , Feminino , Reprodutibilidade dos Testes , Perna (Membro)/fisiologia , Adulto Jovem , Atletas , Fenômenos Biomecânicos/fisiologia , Movimento/fisiologia
4.
Eur J Appl Physiol ; 123(7): 1543-1551, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36932213

RESUMO

PURPOSE: We aimed to (i) investigate differences in 1-minute sit-to-stand test (1MSTST) performance (i.e., the number of repetitions) between a standardised modality (i.e., starting from a conventional chair with 46 cm seat height) and an individualised modality (i.e., starting with a knee joint flexion angle of 90°), and to (ii) quantify the influence of tibia and femur length on 1MSTST performance. METHODS: Healthy participants were recruited for this randomised crossover study, performing each 1MSTST modality twice in a randomised order. The primary outcome was the number of repetitions in the 1MSTST. Secondary endpoints were the acute responses in peripheral oxygen saturation, heart rate, and leg fatigue and dyspnoea. Additionally, we investigated correlations of performance with knee extensor strength in both modalities. RESULTS: Thirty participants were recruited and completed the study. They achieved significantly less repetitions in the standardised 1MSTST compared to the individualised 1MSTST (B = - 12.1, 95% confidence interval [95% CI] = - 14.8/- 9.4, p < 0.001). We found a significant effect of femur length on 1MSTST performance (B = - 1.6, 95% CI = - 2.6/- 0.7, p = 0.01), tibia length showed significant interaction with the 1MSTST modality (B = 1.2, 95% CI = 0.2/2.2, p = 0.03). CONCLUSION: An individualisation of the 1MSTST starting position to 90° knee flexion angle leads to more repetitions compared to the traditional starting position. The higher repetition count is explained by controlling for differences in tibia length. We recommend individualisation of the 1MSTST, enabling more valid comparisons across populations and study samples. TRIAL REGISTRATION NUMBER: http://www. CLINICALTRIALS: gov , NCT04772417. TRIAL REGISTRATION DATE: February 26, 2021.


Assuntos
Articulação do Joelho , Extremidade Inferior , Humanos , Estudos Cross-Over , Extremidade Inferior/fisiologia , Articulação do Joelho/fisiologia
5.
Psychol Sci ; 33(6): 906-924, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35657777

RESUMO

Negative affect is a fundamental dimension of human emotion. When extreme, it contributes to a variety of adverse outcomes, from physical and mental illness to divorce and premature death. Mechanistic work in animals and neuroimaging research in humans and monkeys have begun to reveal the broad contours of the neural circuits governing negative affect, but the relevance of these discoveries to everyday distress remains incompletely understood. Here, we used a combination of approaches-including neuroimaging assays of threat anticipation and emotional-face perception and more than 10,000 momentary assessments of emotional experience-to demonstrate that individuals who showed greater activation in a cingulo-opercular circuit during an anxiety-eliciting laboratory paradigm experienced lower levels of stressor-dependent distress in their daily lives (ns = 202-208 university students). Extended amygdala activation was not significantly related to momentary negative affect. These observations provide a framework for understanding the neurobiology of negative affect in the laboratory and in the real world.


Assuntos
Tonsila do Cerebelo , Ansiedade , Tonsila do Cerebelo/diagnóstico por imagem , Animais , Ansiedade/psicologia , Emoções/fisiologia , Humanos , Imageamento por Ressonância Magnética , Neuroimagem
6.
COPD ; 19(1): 339-344, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-36166273

RESUMO

Approximately, half of COPD patients die from cardiovascular diseases. A prolongation of cardiac repolarization (measured as QTc interval) is associated with cardiovascular events or cardiovascular deaths in populations of older adults and COPD. One way to reduce the QTc could be to increase physical activity (PA). We investigated whether QTc can be reduced by an increase in PA in patients with severe COPD. This is a secondary outcome analysis from a randomized controlled trial investigating the effects of a 3 months pedometer based program to improve PA. 12-lead ECG was assessed at baseline and after 3 months. We measured PA using a validated triaxial accelerometer. Data were analyzed from 59 participants. Multiple regression modeling, including adjustment for baseline QTc, sex, QT prolonging medications, BMI, smoking status and FEV1%, showed no evidence for an association between an improvement of ≥15% PA and QTc reduction. A 15% improvement in PA according to step counts over 3 months seems not to reduce QTc interval by its MCID of 20 ms in patients with severe to very severe COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Actigrafia , Idoso , Eletrocardiografia , Exercício Físico , Coração , Humanos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/terapia
7.
J Neurosci ; 40(41): 7949-7964, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32958570

RESUMO

When extreme, anxiety-a state of distress and arousal prototypically evoked by uncertain danger-can be debilitating. Uncertain anticipation is a shared feature of situations that elicit signs and symptoms of anxiety across psychiatric disorders, species, and assays. Despite the profound significance of anxiety for human health and wellbeing, the neurobiology of uncertain-threat anticipation remains unsettled. Leveraging a paradigm adapted from animal research and optimized for fMRI signal decomposition, we examined the neural circuits engaged during the anticipation of temporally uncertain and certain threat in 99 men and women. Results revealed that the neural systems recruited by uncertain and certain threat anticipation are anatomically colocalized in frontocortical regions, extended amygdala, and periaqueductal gray. Comparison of the threat conditions demonstrated that this circuitry can be fractionated, with frontocortical regions showing relatively stronger engagement during the anticipation of uncertain threat, and the extended amygdala showing the reverse pattern. Although there is widespread agreement that the bed nucleus of the stria terminalis and dorsal amygdala-the two major subdivisions of the extended amygdala-play a critical role in orchestrating adaptive responses to potential danger, their precise contributions to human anxiety have remained contentious. Follow-up analyses demonstrated that these regions show statistically indistinguishable responses to temporally uncertain and certain threat anticipation. These observations provide a framework for conceptualizing anxiety and fear, for understanding the functional neuroanatomy of threat anticipation in humans, and for accelerating the development of more effective intervention strategies for pathological anxiety.SIGNIFICANCE STATEMENT Anxiety-an emotion prototypically associated with the anticipation of uncertain harm-has profound significance for public health, yet the underlying neurobiology remains unclear. Leveraging a novel neuroimaging paradigm in a relatively large sample, we identify a core circuit responsive to both uncertain and certain threat anticipation, and show that this circuitry can be fractionated into subdivisions with a bias for one kind of threat or the other. The extended amygdala occupies center stage in neuropsychiatric models of anxiety, but its functional architecture has remained contentious. Here we demonstrate that its major subdivisions show statistically indistinguishable responses to temporally uncertain and certain threat. Collectively, these observations indicate the need to revise how we think about the neurobiology of anxiety and fear.


Assuntos
Antecipação Psicológica , Transtornos de Ansiedade/psicologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Transtornos de Ansiedade/diagnóstico por imagem , Transtornos de Ansiedade/fisiopatologia , Mapeamento Encefálico , Estimulação Elétrica , Medo , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Resposta Galvânica da Pele , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Substância Cinzenta Periaquedutal/diagnóstico por imagem , Substância Cinzenta Periaquedutal/fisiopatologia , Estimulação Luminosa , Estudos Prospectivos , Núcleos Septais/diagnóstico por imagem , Núcleos Septais/fisiopatologia , Incerteza , Adulto Jovem
8.
Neurourol Urodyn ; 38(6): 1657-1662, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31134684

RESUMO

AIMS: The aim of this study was to identify the problems and resources of women with urinary or fecal incontinence based on the International Classification of Function and Health (ICF) framework and detecting the impact on the personal environment and quality of life. This study forms part of a project with an overall goal to enable standardized planning and evaluation of interventions in multi-professional settings. METHODS: To answer the study question a mixed-method sequential design with a priority to the quantitative approach was considered appropriate. Regarding methods, focus groups were chosen to collect data. Transcripts were analyzed with content analysis and identified concepts linked to the corresponding ICF categories by two different raters. Cohen's kappa was calculated for interrater reliability. RESULTS: Thirteen women with a mean age of 69.9 years were recruited. Four focus groups were conducted, whereas saturation was reached after two focus groups. Overall transcripts 99 defined ICF categories at second level could be linked (body functions = 31, body structures = 5, activities and participation = 33, and environmental factors = 30) whereas 4 categories were not sufficiently covered by the ICF (3 = personal factors, 1 = not covered). CONCLUSIONS: This study has determined 103 resources and problems based on the ICF model of women with urinary and/or fecal incontinence. In spite of these results, it was shown that four concepts are not fully covered by the ICF framework. The current data highlight the importance of an extension of the ICF model, especially towards the personal factors of patients.


Assuntos
Atividades Cotidianas/psicologia , Incontinência Fecal/psicologia , Qualidade de Vida/psicologia , Inquéritos e Questionários , Incontinência Urinária/psicologia , Idoso , Idoso de 80 Anos ou mais , Avaliação da Deficiência , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
9.
Neurourol Urodyn ; 38(6): 1663-1668, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31129925

RESUMO

AIMS: This study seeks to explore barriers faced by and resources available to male patients with urinary (UI) and/or fecal incontinence (FI) based on the ICF framework. As a result, this study contributes to the development of the ICF-Incontinence Assessment Form (ICF-IAF), which is designed to be a standardized planning and evaluation tool for interventions in a multidisciplinary setting. METHODS: A mixed-method sequential design that places emphasis on the quantitative approach was considered appropriate for this study. Focus group interviews (FG) were chosen to collect data. Data were analysed with deductive content analysis and themes identified during FG were linked to the most corresponding ICF categories by two raters. Cohen's κ was calculated to determine interrater reliability. RESULTS: Four FG were conducted with a total of 13 male participants. The mean age of the participants was 74.7 years. A total of 73 barriers and resources on the second ICF level (body functions 26, body structures five, activities and participation 26 and environmental factors 16), whereby four categories were not sufficiently covered by the ICF, could be identified. The κ score for the two raters was 0.82. CONCLUSIONS: While barriers are fundamental factors affecting patients, this study found that resources are as important and should not be overlooked in the conventional treatment in both UI and FI-specific assessments.


Assuntos
Atividades Cotidianas/psicologia , Incontinência Fecal/psicologia , Qualidade de Vida/psicologia , Inquéritos e Questionários , Incontinência Urinária/psicologia , Idoso , Idoso de 80 Anos ou mais , Avaliação da Deficiência , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
10.
Neurourol Urodyn ; 38(4): 1053-1066, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30803015

RESUMO

AIMS: Current level-A recommended questionnaires that provide a valid assessment of urinary incontinence (UI) and/or faecal incontinence (FI), but do not cover all aspects of the burden of the disease in the sense of the bio-psycho-social model of the World Health Organization's International Classification of Functioning, Disability and Health (ICF). Therefore, an ICF oriented questionnaire for patients with UI and/or FI to assess treatment barriers (problems) as well as positive influencing factors (resources), the "ICF-Incontinence Assessment Form" will be developed. The aim of this preliminary study was (a) to identify problems and resources of UI and/or FI in current level-A recommended questionnaires and (b) to evaluate problems and resources of patients with UI and/or FI from the perspective of experienced physiotherapists. METHODS: (a) Current level-A recommended questionnaires for UI and/or FI were analyzed. Questions were linked to the ICF categories. (b) A 3-round Delphi technique survey among 262 physiotherapists from five German-speaking countries was used to evaluate patients' problems and resources relevant to physiotherapy. RESULTS: (a) A total of 27 identified questionnaires were linked to 110 ICF categories. No positive influencing factors could be identified. (b) After Delphi-round 3, 110 categories of problems and 71 resources were identified. CONCLUSION: Since there is a lack of resource items in the present validated questionnaires, there is a need for a short, practical questionnaire to assess and monitor both, problems and resources of patients with UI and/or FI.


Assuntos
Incontinência Fecal/diagnóstico , Incontinência Urinária/diagnóstico , Técnica Delphi , Avaliação da Deficiência , Pessoas com Deficiência , Gerenciamento Clínico , Incontinência Fecal/terapia , Humanos , Inquéritos e Questionários , Incontinência Urinária/terapia
11.
Cogn Emot ; 30(5): 968-84, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-25966279

RESUMO

Prior research showed that mere instructions about the contingency between a conditioned stimulus (CS) and an unconditioned stimulus (US) can generate fear reactions to the CS. Little is known, however, about the extent to which actual CS-US contingency experience adds anything beyond the effect of contingency instructions. Our results extend previous studies on this topic in that it included fear potentiated startle as an additional dependent variable and examined return of fear (ROF) following reinstatement. We observed that CS-US pairings can enhance fear reactions beyond the effect of contingency instructions. Moreover, for all measures of fear, instructions elicited immediate fear reactions that could not be completely overridden by subsequent situational safety information. Finally, ROF following reinstatement for instructed CS+s was unaffected by actual experience. In summary, our results demonstrate the power of contingency instructions and reveal the additional impact of actual experience of CS-US pairings.


Assuntos
Condicionamento Psicológico/fisiologia , Medo/psicologia , Reflexo de Sobressalto/fisiologia , Adulto , Feminino , Resposta Galvânica da Pele/fisiologia , Humanos , Masculino
12.
bioRxiv ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36798350

RESUMO

Neuroticism/Negative Emotionality (N/NE)-the tendency to experience anxiety, fear, and other negative emotions-is a fundamental dimension of temperament with profound consequences for health, wealth, and wellbeing. Elevated N/NE is associated with a panoply of adverse outcomes, from reduced socioeconomic attainment and divorce to mental illness and premature death. Work in animals suggests that N/NE reflects heightened reactivity to uncertain threat in the bed nucleus of the stria terminalis (BST) and central nucleus of the amygdala (Ce), but the relevance of these discoveries to the human brain and temperament have remained unclear. Here we used a combination of psychometric, psychophysiological, and neuroimaging approaches to rigorously test this hypothesis in an ethnoracially diverse sample of 220 emerging adults selectively recruited to encompass a broad spectrum of N/NE. Cross-validated robust-regression analyses demonstrated that N/NE is selectively associated with heightened BST activation during the uncertain anticipation of a genuinely distressing threat. In contrast, N/NE was unrelated to BST activation during certain-threat anticipation, Ce activation during either type of threat anticipation, or BST/Ce reactivity to 'threat-related' faces. Implicit in much of the neuroimaging literature is the assumption that different threat paradigms are statistically interchangeable probes of individual differences in neural function, yet our results revealed negligible evidence of convergence between popular threat-anticipation and emotional-face tasks. These observations provide a framework for conceptualizing emotional traits and disorders; for guiding the design and interpretation of biobank and other neuroimaging studies of psychiatric risk, disease, and treatment; and for informing the next generation of mechanistic research.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38401881

RESUMO

BACKGROUND: Deeper phenotyping may improve our understanding of depression. Because depression is heterogeneous, extracting cognitive signatures associated with severity of depressive symptoms, anhedonia, and affective states is a promising approach. METHODS: Sequential sampling models decomposed behavior from an adaptive approach-avoidance conflict task into computational parameters quantifying latent cognitive signatures. Fifty unselected participants completed clinical scales and the approach-avoidance conflict task by either approaching or avoiding trials offering monetary rewards and electric shocks. RESULTS: Decision dynamics were best captured by a sequential sampling model with linear collapsing boundaries varying by net offer values, and with drift rates varying by trial-specific reward and aversion, reflecting net evidence accumulation toward approach or avoidance. Unlike conventional behavioral measures, these computational parameters revealed distinct associations with self-reported symptoms. Specifically, passive avoidance tendencies, indexed by starting point biases, were associated with greater severity of depressive symptoms (R = 0.34, p = .019) and anhedonia (R = 0.49, p = .001). Depressive symptoms were also associated with slower encoding and response execution, indexed by nondecision time (R = 0.37, p = .011). Higher reward sensitivity for offers with negative net values, indexed by drift rates, was linked to more sadness (R = 0.29, p = .042) and lower positive affect (R = -0.33, p = .022). Conversely, higher aversion sensitivity was associated with more tension (R = 0.33, p = .025). Finally, less cautious response patterns, indexed by boundary separation, were linked to more negative affect (R = -0.40, p = .005). CONCLUSIONS: We demonstrated the utility of multidimensional computational phenotyping, which could be applied to clinical samples to improve characterization and treatment selection.


Assuntos
Anedonia , Depressão , Recompensa , Humanos , Anedonia/fisiologia , Masculino , Feminino , Adulto , Depressão/fisiopatologia , Adulto Jovem , Testes Neuropsicológicos , Tomada de Decisões/fisiologia , Simulação por Computador , Cognição/fisiologia , Afeto/fisiologia
14.
BMC Sports Sci Med Rehabil ; 16(1): 172, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148127

RESUMO

PURPOSE: Blood-flow restriction (BFR) endurance training may increase endurance performance and muscle strength similar to traditional endurance training while requiring a lower training intensity. We aimed to compare acute cardiorespiratory responses to low-intensity interval exercise under BFR with moderate-intensity traditional interval exercise (TRA). METHODS: We conducted a randomized crossover study. The protocol involved three cycling intervals interspersed with 1 min resting periods. With a 48-h washout period, individuals performed the protocol twice in random order: once as BFR-50 (i.e., 50% incremental peak power output [IPPO] and 50% limb occlusion pressure [LOP]) and once as TRA-65 (65% IPPO without occlusion). TRA-65 intervals lasted 2 min, and time-matched BFR-50 lasted 2 min and 18 s. Respiratory parameters were collected by breath-by-breath analysis. The ratings of perceived breathing and leg exertion (RPE, 0 to 10) were assessed. Linear mixed models were used for analysis. RESULTS: Out of the 28 participants initially enrolled in the study, 24 healthy individuals (18 males and 6 females) completed both measurements. Compared with TRA-65, BFR-50 elicited lower minute ventilation (VE, primary outcome) (-3.1 l/min [-4.4 to -1.7]), oxygen consumption (-0.22 l/min [-0.28 to -0.16]), carbon dioxide production (-0.25 l/min [-0.29 to -0.20]) and RPE breathing (-0.9 [-1.2 to -0.6]). RPE leg was significantly greater in the BFR-50 group (1.3 [1.0 to 1.7]). CONCLUSION: BFR endurance exercise at 50% IPPO and 50% LOP resulted in lower cardiorespiratory work and perceived breathing effort compared to TRA at 65% IPPO. BFR-50 could be an attractive alternative for TRA-65, eliciting less respiratory work and perceived breathing effort while augmenting perceived leg muscle effort. TRIAL REGISTRATION: NCT05163600; December 20, 2021.

15.
bioRxiv ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39026814

RESUMO

Temporal dynamics play a central role in models of emotion: "fear" is widely conceptualized as a phasic response to certain-and-imminent danger, whereas "anxiety" is a sustained response to uncertain-or-distal harm. Yet the underlying human neurobiology remains contentious. Leveraging an ethnoracially diverse sample, translationally relevant paradigm, and theory-driven modeling approach, we demonstrate that certain and uncertain threat recruit a shared threat-anticipation circuit. This cortico-subcortical circuit exhibits persistently elevated activation when anticipating uncertain-threat encounters and a transient burst of activation in the moments before certain encounters. For many scientists and clinicians, feelings are the defining feature of human fear and anxiety. Here we used an independently validated brain signature to covertly decode the momentary dynamics of anticipatory distress for the first time. Results mirrored the dynamics of neural activation. These observations provide fresh insights into the neurobiology of threat-elicited emotions and set the stage for more ambitious clinical and mechanistic research.

16.
Comput Psychiatr ; 8(1): 46-69, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774430

RESUMO

The Probabilistic Reward Task (PRT) is widely used to investigate the impact of Major Depressive Disorder (MDD) on reinforcement learning (RL), and recent studies have used it to provide insight into decision-making mechanisms affected by MDD. The current project used PRT data from unmedicated, treatment-seeking adults with MDD to extend these efforts by: (1) providing a more detailed analysis of standard PRT metrics-response bias and discriminability-to better understand how the task is performed; (2) analyzing the data with two computational models and providing psychometric analyses of both; and (3) determining whether response bias, discriminability, or model parameters predicted responses to treatment with placebo or the atypical antidepressant bupropion. Analysis of standard metrics replicated recent work by demonstrating a dependency between response bias and response time (RT), and by showing that reward totals in the PRT are governed by discriminability. Behavior was well-captured by the Hierarchical Drift Diffusion Model (HDDM), which models decision-making processes; the HDDM showed excellent internal consistency and acceptable retest reliability. A separate "belief" model reproduced the evolution of response bias over time better than the HDDM, but its psychometric properties were weaker. Finally, the predictive utility of the PRT was limited by small samples; nevertheless, depressed adults who responded to bupropion showed larger pre-treatment starting point biases in the HDDM than non-responders, indicating greater sensitivity to the PRT's asymmetric reinforcement contingencies. Together, these findings enhance our understanding of reward and decision-making mechanisms that are implicated in MDD and probed by the PRT.

17.
Psychophysiology ; 60(7): e14253, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36727722

RESUMO

Exposure to adverse experiences is a well-established major risk factor for affective psychopathology. The vulnerability of deleterious sequelae is assumed in maladaptive processes of the defensive system, particularly in emotional processing. More specifically, childhood maltreatment has been suggested to be associated with the recruitment of specific and distinct defensive response profiles. To date, it remains unclear whether these are specific or generalizable to recent adversity in adulthood. This pre-registered study aimed to investigate the impact of exposure to childhood and recent adversity on emotional processing in 685 healthy adults with the "Affective Startle Modulation" Paradigm (ASM). First, we replicated higher trait anxiety and depression levels in individuals exposed to both types of adversity. Second, we observed increased general skin conductance reactivity in individuals exposed to recent adversity. Third, individuals exposed to childhood maltreatment showed reduced, while individuals exposed to recent adversity showed increased discrimination between pictures of negative and neutral valence, compared with non-exposed individuals in SCR. No association between exposure to adversity and fear potentiated startle was observed. Furthermore, explorative analyses revealed moderate dimensional and categorical agreement between two childhood maltreatment questionnaires and provide insight into potential adversity-type specific effects. Our results support experience-dependent plasticity in sympathetic nervous system reactivity and suggest distinct response profiles in affective modulation in individuals exposed to early versus recent adversity. We emphasize the need to further explore distinct adversity profiles to further our understanding on specific psychophysiological profiles and their potential implication for prevention and intervention.


Assuntos
Maus-Tratos Infantis , Emoções , Humanos , Adulto , Criança , Emoções/fisiologia , Medo/fisiologia , Ansiedade , Transtornos de Ansiedade , Maus-Tratos Infantis/psicologia
18.
Psychophysiology ; 60(12): e14364, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37402156

RESUMO

The startle response is a cross-species defensive reflex that is considered a key tool for cross-species translational emotion research. While the neural pathway mediating (affective) startle modulation has been extensively studied in rodents, human work on brain-behavior interactions has lagged in the past due to technical challenges, which have only recently been overcome through non-invasive simultaneous EMG-fMRI assessments. We illustrate key paradigms and methodological tools for startle response assessment in rodents and humans and review evidence for primary and modulatory neural circuits underlying startle responses and their affective modulation in humans. Based on this, we suggest a refined and integrative model for primary and modulatory startle response pathways in humans concluding that there is strong evidence from human work on the neurobiological pathway underlying the primary startle response while evidence for the modulatory pathway is still sparse. In addition, we provide methodological considerations to guide future work and provide an outlook on new and exciting perspectives enabled through technical and theoretical advances outlined in this work.


Assuntos
Encéfalo , Reflexo de Sobressalto , Humanos , Reflexo de Sobressalto/fisiologia , Eletromiografia , Encéfalo/fisiologia , Emoções/fisiologia
19.
Brain Sci ; 13(8)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37626488

RESUMO

Fear extinction is the basis of exposure therapies for posttraumatic stress disorder (PTSD), but half of patients do not improve. Predicting fear extinction in individuals with PTSD may inform personalized exposure therapy development. The participants were 125 trauma-exposed adults (96 female) with a range of PTSD symptoms. Electromyography, electrocardiogram, and skin conductance were recorded at baseline, during dark-enhanced startle, and during fear conditioning and extinction. Using a cross-validated, hold-out sample prediction approach, three penalized regressions and conventional ordinary least squares were trained to predict fear-potentiated startle during extinction using 50 predictor variables (5 clinical, 24 self-reported, and 21 physiological). The predictors, selected by penalized regression algorithms, were included in multivariable regression analyses, while univariate regressions assessed individual predictors. All the penalized regressions outperformed OLS in prediction accuracy and generalizability, as indexed by the lower mean squared error in the training and holdout subsamples. During early extinction, the consistent predictors across all the modeling approaches included dark-enhanced startle, the depersonalization and derealization subscale of the dissociative experiences scale, and the PTSD hyperarousal symptom score. These findings offer novel insights into the modeling approaches and patient characteristics that may reliably predict fear extinction in PTSD. Penalized regression shows promise for identifying symptom-related variables to enhance the predictive modeling accuracy in clinical research.

20.
ERJ Open Res ; 9(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36699651

RESUMO

Research question: The assessment of cough frequency in clinical practice relies predominantly on the patient's history. Currently, objective evaluation of cough is feasible with bulky equipment during a brief time (i.e. hours up to 1 day). Thus, monitoring of cough has been rarely performed outside clinical studies. We developed a small wearable cough detector (SIVA-P3) that uses deep neural networks for the automatic counting of coughs. This study examined the performance of the SIVA-P3 in an outpatient setting. Methods: We recorded cough epochs with SIVA-P3 over eight consecutive days in patients suffering from chronic cough. During the first 24 h, the detector was validated against cough events counted by trained human listeners. The wearing comfort and the device usage were assessed using a questionnaire. Results: In total, 27 participants (mean±sd age 50±14 years) with either chronic unexplained cough (n=12), COPD (n=4), asthma (n=5) or interstitial lung disease (n=6) were studied. During the daytime, the sensitivity of SIVA-P3 cough detection was 88.5±2.49% and the specificity was 99.97±0.01%. During the night-time, the sensitivity was 84.15±5.04% and the specificity was 99.97±0.02%. The wearing comfort and usage of the device was rated as very high by most participants. Conclusion: SIVA-P3 enables automatic continuous cough monitoring in an outpatient setting for objective assessment of cough over days and weeks. It shows comparable sensitivity or higher sensitivity than other devices with fully automatic cough counting. Thanks to its wearing comfort and the high performance for cough detection, it has the potential for being used in routine clinical practice.

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