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1.
Sex Abuse ; 36(3): 255-291, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36927218

RESUMEN

The present meta-analysis is an update of the meta-analysis by Schmucker and Lösel [Campbell Syst. Rev. 2017; 13: 1-75], which synthesized evidence on sexual recidivism as an indicator of treatment effectiveness in persons with sexual offense histories. The updated meta-analysis includes 37 samples comprising a total of 30,394 individuals with sexual offense histories, which is nearly three times the sample size reported by Schmucker and Lösel (2017: 28 samples, N = 9781). In line with Schmucker and Lösel (2017), the mean treatment effect was small with an odds ratio of 1.54 [95% CI 1.22, 1.95] (p < .001). A moderator analysis suggested three predictors of importance, i.e., risk level, treatment specialization, and author confounding. Greater treatment effectiveness was suggested in high- and medium-compared to low-risk individuals and in specialized compared to non-specialized treatments. Authors affiliated with treatment programs reported larger effectiveness than independent authors. These findings were overall in line with Schmucker and Lösel (2017), though the effects of risk level and treatment specialization were stronger in the current meta-analysis. The findings of the updated meta-analysis reinforce the evidence for the first and second principle of the Risk-Need-Responsivity model. The results may support researchers and decision-makers in interpreting the current evidence on sexual recidivism as an indicator of treatment effectiveness, and, based on that, implement and carry out informative, methodologically sound evaluations of ongoing treatment programs in persons with sexual offense histories.


Asunto(s)
Reincidencia , Delitos Sexuales , Humanos , Conducta Sexual , Resultado del Tratamiento , Medición de Riesgo
2.
Psychol Assess ; 36(2): 134-146, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38059959

RESUMEN

The Static-99, Static-99R, and STABLE-2007 are internationally well-established instruments for predicting static and dynamic risks of sexual recidivism in individuals convicted of sexual offenses. Previous meta-analyses assessed their predictive and incremental validity, but none has yet compared the two Static versions and the Static-STABLE combinations. Here, we implemented diagnostic test accuracy network meta-analysis (DTA-NMA) to compare all tests and identify optimal cutoffs in one comprehensive analysis. The DTA-NMA included 32 samples comprising 45,224 adult male individuals. More information was available on the Static-99 (22 samples; 34,316 individuals) and the Static-99R (13 samples; 27,243 individuals), compared to the Static-99/STABLE-2007 (three samples; 762 individuals), the Static-99R/STABLE-2007 (two samples; 2,972 individuals), and the STABLE-2007 (three samples; 816 individuals). The primary outcome was the area under the receiver operating characteristic curve (AUC). The secondary outcomes were sensitivity and specificity. Optimal cutoffs were determined using the Youden index. The AUC suggested moderate predictive validity for Static-99 and Static-99R, whereas STABLE-2007 had no predictive value. The optimal cutoff of Static-99R was suggested to have higher specificity than that of Static-99, whereas sensitivity was comparable between instruments. The notion of incremental validity for STABLE-2007 could not be confirmed. This work represents the first meta-analysis to compare Static-99, Static-99R, STABLE-2007, and their combinations in one analysis. Static-99R demonstrated the highest specificity in predicting the risk of sexual recidivism, indicating a potential advantage in detecting true nonrecidivists. The findings are discussed, considering the current recommendations for assessing the risk of sexual recidivism in the criminal justice system. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Criminales , Reincidencia , Delitos Sexuales , Adulto , Humanos , Masculino , Medición de Riesgo , Metaanálisis en Red , Pruebas Diagnósticas de Rutina
4.
BMC Psychiatry ; 21(1): 129, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33673822

RESUMEN

BACKGROUND: Conditional power of network meta-analysis (NMA) can support the planning of randomized controlled trials (RCTs) assessing medical interventions. Conditional power is the probability that updating existing inconclusive evidence in NMA with additional trial(s) will result in conclusive evidence, given assumptions regarding trial design, anticipated effect sizes, or event probabilities. METHODS: The present work aimed to estimate conditional power for potential future trials on antidepressant treatments. Existing evidence was based on a published network of 502 RCTs conducted between 1979-2018 assessing acute antidepressant treatment in major depressive disorder (MDD). Primary outcomes were efficacy in terms of the symptom change on the Hamilton Depression Scale (HAMD) and tolerability in terms of the dropout rate due to adverse events. The network compares 21 antidepressants consisting of 231 relative treatment comparisons, 164 (efficacy) and 127 (tolerability) of which are currently assumed to have inconclusive evidence. RESULTS: Required sample sizes to achieve new conclusive evidence with at least 80% conditional power were estimated to range between N = 894 - 4190 (efficacy) and N = 521 - 1246 (tolerability). Otherwise, sample sizes ranging between N = 49 - 485 (efficacy) and N = 40 - 320 (tolerability) may require stopping for futility based on a boundary at 20% conditional power. Optimizing trial designs by considering multiple trials that contribute both direct and indirect evidence, anticipating alternative effect sizes or alternative event probabilities, may increase conditional power but required sample sizes remain high. Antidepressants having the greatest conditional power associated with smallest required sample sizes were identified as those on which current evidence is low, i.e., clomipramine, levomilnacipran, milnacipran, nefazodone, and vilazodone, with respect to both outcomes. CONCLUSIONS: The present results suggest that conditional power to achieve new conclusive evidence in ongoing or future trials on antidepressant treatments is low. Limiting the use of the presented conditional power analysis are primarily due to the estimated large sample sizes which would be required in future trials as well as due to the well-known small effect sizes in antidepressant treatments. These findings may inform researchers and decision-makers regarding the clinical relevance and justification of research in ongoing or future antidepressant RCTs in MDD.


Asunto(s)
Antidepresivos , Trastorno Depresivo Mayor , Antidepresivos/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Humanos , Metaanálisis en Red
5.
BMC Psychiatry ; 20(1): 437, 2020 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-32894088

RESUMEN

BACKGROUND: The issue of unblinded outcome-assessors and patients has repeatedly been stressed as a flaw in allegedly double-blind antidepressant trials. Unblinding bias can for example result from a drug's marked side effects. If such unblinding bias is present for a given drug, then it might be expected that the placebos of that drug are rated significantly less effective than that of other antidepressants. METHODS: To test this hypothesis, the present exploratory analysis conducted a Bayesian network meta-analysis (NMA) comparing the efficacy of 19 different placebos in placebo-controlled trials provided in the dataset by Cipriani et al. (Lancet 2018; 391: 1357-66). Primary outcome was efficacy (continuous) estimated on the standardized mean difference (SMD) scale and defined as the pre-post change on the Hamilton Depression scale (HAMD-17), on which information was available in N = 258 trials. RESULTS: Comparative placebo ranking suggested mirtazapine-placebo (SMD -2.0 [- 5.0-1.0 95% CrI]) to be the most, and amitriptyline- (SMD 1.2 [- 1.6-3.9 95% CrI]) and trazodone- (SMD 2.1 [- 0.9-5.2 95% CrI]) placebos to be the least effective placebos. Other placebos suggested to be more effective than amitriptyline- and trazodone-placebos (based on 95% CrIs excluding zero) were citalopram, desvenlafaxine, duloxetine, escitalopram, fluoxetine, sertraline, and venlafaxine placebos. These NMA results were corroborated by the observation that the relative efficacy between drug and placebo was considerably larger for amitriptyline and trazodone than for instance mirtazapine, duloxetine, and venlafaxine, supported by a small and insignificant correlation between drug-efficacy and placebo-efficacy (r = - 0.202, p = 0.408). DISCUSSION: The present exploratory NMA indicates that distinguishable side effects of older drugs may unblind outcome-assessors thus resulting in overestimation of the average drug-placebo difference and underrating bias in placebo-arms, particularly for the older antidepressant drugs amitriptyline and trazodone. If confirmed in prospective studies, these findings suggest that efficacy rankings for antidepressants are susceptible to bias and should be considered unreliable or misleading. The analysis is limited by the focus on the single-comparison placebos (76%, i.e., placebos assessed in two-arm trials), since double-comparison placebos (25%, i.e., placebos assessed in three-arm trials) are hard to interpret and therefore not included in the present interpretation. Another limitation is the problem of multiplicity, which was only approximately accounted for in the Bayesian NMA by modelling treatment effects as exchangeable.


Asunto(s)
Trastorno Depresivo Mayor , Antidepresivos/uso terapéutico , Teorema de Bayes , Depresión , Trastorno Depresivo Mayor/tratamiento farmacológico , Humanos , Estudios Prospectivos
6.
Front Psychiatry ; 11: 633, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848900

RESUMEN

BACKGROUND: Recent meta-analyses reported placebo response rate in antidepressant trials to be stable since the 1970s. These meta-analyses however were limited in considering only linear time trends, assessed trial-level covariates based on single-model hypothesis testing only, and did not adjust for small-study effects (SSE), a well-known but not yet formally assessed bias in antidepressant trials. METHODS: This secondary meta-analysis extends previous work by modeling nonlinear time trends, assessing the relative importance of trial-level covariates using a multimodel approach, and rigorously adjusting for SSE. Outcomes were placebo efficacy (continuous), based on the Hamilton Depression Scale, and placebo response rate. RESULTS: Results suggested that any nonlinear time trends in both placebo efficacy (continuous) and response rate were best explained by SSE. Adjusting for SSE revealed a significant gradual increase in placebo efficacy (continuous) from 1979 to 2014. A similar observation was made for placebo response rate, but did not reach significance due higher susceptibility to SSE. By contrast, trial-level covariates alone were found to be insufficient in explaining time trends. CONCLUSION: The present findings contribute to the ongoing debate on antidepressant placebo outcomes and highlight the need to adjust for bias introduced by SSE. The results are of clinical relevance because SSE may affect the evaluation of success or failure in antidepressant trials.

7.
PLoS Comput Biol ; 15(11): e1007443, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31725719

RESUMEN

Human decisions can be habitual or goal-directed, also known as model-free (MF) or model-based (MB) control. Previous work suggests that the balance between the two decision systems is impaired in psychiatric disorders such as compulsion and addiction, via overreliance on MF control. However, little is known whether the balance can be altered through task training. Here, 20 healthy participants performed a well-established two-step task that differentiates MB from MF control, across five training sessions. We used computational modelling and functional near-infrared spectroscopy to assess changes in decision-making and brain hemodynamic over time. Mixed-effects modelling revealed overall no substantial changes in MF and MB behavior across training. Although our behavioral and brain findings show task-induced changes in learning rates, these parameters have no direct relation to either MF or MB control or the balance between the two systems, and thus do not support the assumption of training effects on MF or MB strategies. Our findings indicate that training on the two-step paradigm in its current form does not support a shift in the balance between MF and MB control. We discuss these results with respect to implications for restoring the balance between MF and MB control in psychiatric conditions.


Asunto(s)
Toma de Decisiones/fisiología , Adulto , Encéfalo/fisiología , Mapeo Encefálico/métodos , Femenino , Voluntarios Sanos , Humanos , Aprendizaje/fisiología , Masculino , Modelos Teóricos , Motivación/fisiología , Recompensa , Espectroscopía Infrarroja Corta/métodos , Adulto Joven
8.
Depress Anxiety ; 36(8): 766-779, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31111623

RESUMEN

BACKGROUND: Brain mitochondrial dysfunction is implicated in the pathophysiology of mood disorders. Brain cytochrome-c-oxidase (COX) activity is associated with the mitochondrial function. Near-infrared spectroscopy (NIRS) noninvasively measures oxidized COX (oxCOX) and tissue oxygenation index (TOI) reflecting cerebral blood flow and oxygenation. METHODS: oxCOX and TOI were assessed in prefrontal cortex (Fp1/2, Brodmann area 10) in patients in a major depressive episode (N = 13) with major depressive disorder (MDD; N = 7) and bipolar disorder (BD; N = 6) compared with the controls (N = 10). One patient with MDD and all the patients with BD were taking medications. Computational modeling estimated oxCOX and TOI related indices of mitochondrial function and cerebral blood flow, respectively. RESULTS: oxCOX was lower in patients than controls (p = .014) correlating inversely with depression severity (r = -.72; p = .006), driven primarily by lower oxCOX in BD compared with the controls. Computationally modeled mitochondrial parameters of the electron transport chain, such as the nicotinamide adenine dinucleotide ratio (NAD+ /NADH; p = .001) and the proton leak rate across the inner mitochondrial membrane (klk2 ; p = .008), were also lower in patients and correlated inversely with depression severity. No such effects were found for TOI. CONCLUSIONS: In this pilot study, oxCOX and related mitochondrial parameters assessed by NIRS indicate an abnormal cerebral metabolic state in mood disorders proportional to depression severity, potentially providing a biomarker of antidepressant effect. Because the effect was driven by the medicated BD group, findings need to be evaluated in a larger, medication-free population.


Asunto(s)
Encéfalo/metabolismo , Encéfalo/fisiopatología , Trastorno Depresivo Mayor/metabolismo , Trastorno Depresivo Mayor/fisiopatología , Complejo IV de Transporte de Electrones/metabolismo , Mitocondrias/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Mapeo Encefálico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/fisiología , Proyectos Piloto , Espectroscopía Infrarroja Corta , Adulto Joven
9.
J Biomed Opt ; 23(5): 1-9, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29766685

RESUMEN

Functional near-infrared spectroscopy (fNIRS) is a noninvasive method for measuring in vivo both hemodynamic and mitochondrial metabolic activities in brain cortical structures. Although the test-retest reliability of the hemodynamic measures, such as reflected by oxygenated (HbO2), deoxygenated (HHb) hemoglobin, and the tissue oxygenation index (TOI), has been previously reported to be good to excellent, the reliability of the metabolic signal indexed by oxidized cytochrome-c-oxidase (oxCCO) has not been reported. The present test-retest study compared the reliability of the metabolic and hemodynamic signals in 10 healthy participants undergoing hypo- and hypercapnia challenges. The primary reliability measure was the intraclass correlation coefficient (ICC). Results of both hypo- and hypercapnia showed that the oxCCO signal (ICC = 0.876 / 0.757) had robust reliability comparable with that of the HbO2 (ICC = 0.841 / 0.801), HHb (ICC = 0.804 / 0.571), and TOI (ICC = 0.574 / 0.614) signals. These findings show that the oxCCO signal can be assessed by fNIRS with comparable reliability to the hemodynamic measures. We discuss the results in light of current interest in a mitochondrial metabolic marker derived from fNIRS.


Asunto(s)
Encéfalo , Complejo IV de Transporte de Electrones/sangre , Procesamiento de Señales Asistido por Computador , Espectroscopía Infrarroja Corta/métodos , Adulto , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Encéfalo/enzimología , Femenino , Hemoglobinas/análisis , Humanos , Hipercapnia , Hipocapnia , Masculino , Oxidación-Reducción , Oxihemoglobinas/análisis , Reproducibilidad de los Resultados
10.
Soc Cogn Affect Neurosci ; 13(5): 513-524, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29635351

RESUMEN

Humans typically display inequality aversion in social situations, which manifests itself as a preference for fairer distributions of resources. However, people differ in the degree to which they dislike being worse off [disadvantageous inequality (DI) aversion] or better off [advantageous inequality (AI) aversion] than others. Competing models explain such behavior by focusing on aversion to payoff differences, maximization of total payoff or reciprocity. Using functional near-infrared spectroscopy, we asked which of these theories could better explain dorsolateral prefrontal cortex (dlPFC) activity while participants accepted or punished fair vs unfair monetary transfers in an anonymous norm compliance task. We found that while all participants exhibited DI aversion, there were substantial differences in preferences for AI, which were strongly predicted by dlPFC activation. Model comparisons revealed that both punishment behavior and prefrontal activity were best explained by a model that allowed for AI seeking rather than imposing aversion. Moreover, enhancing this model by taking into account behavioral response times, as a proxy for choice difficulty, further improved model fits. Our data provide evidence that the dlPFC encodes subjective values of payoff inequality and that this representation is richer than envisaged by standard models of social preferences.


Asunto(s)
Corteza Prefrontal/fisiología , Deseabilidad Social , Percepción Social , Algoritmos , Femenino , Juegos Experimentales , Humanos , Masculino , Modelos Psicológicos , Corteza Prefrontal/diagnóstico por imagen , Castigo , Tiempo de Reacción/fisiología , Espectroscopía Infrarroja Corta , Adulto Joven
11.
Neurophotonics ; 4(2): 021106, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28630878

RESUMEN

Broadband near-infrared spectroscopy (NIRS) can provide an endogenous indicator of tissue temperature based on the temperature dependence of the water absorption spectrum. We describe a first evaluation of the calibration and prediction of brain tissue temperature obtained during hypothermia in newborn piglets (animal dataset) and rewarming in newborn infants (human dataset) based on measured body (rectal) temperature. The calibration using partial least squares regression proved to be a reliable method to predict brain tissue temperature with respect to core body temperature in the wavelength interval of 720 to 880 nm with a strong mean predictive power of [Formula: see text] (animal dataset) and [Formula: see text] (human dataset). In addition, we applied regression receiver operating characteristic curves for the first time to evaluate the temperature prediction, which provided an overall mean error bias between NIRS predicted brain temperature and body temperature of [Formula: see text] (animal dataset) and [Formula: see text] (human dataset). We discuss main methodological aspects, particularly the well-known aspect of over- versus underestimation between brain and body temperature, which is relevant for potential clinical applications.

12.
Front Behav Neurosci ; 10: 172, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27660608

RESUMEN

A psychosis phenotype can be observed below the threshold of clinical detection. The study aimed to investigate whether subclinical psychotic symptoms are associated with deficits in controlling emotional interference, and whether cortical brain and cardiac correlates of these deficits can be detected using functional near-infrared spectroscopy (fNIRS). A data set derived from a community sample was obtained from the Zurich Program for Sustainable Development of Mental Health Services. 174 subjects (mean age 29.67 ± 6.41, 91 females) were assigned to four groups ranging from low to high levels of subclinical psychotic symptoms (derived from the Symptom Checklist-90-R). Emotional interference was assessed using the emotional Stroop task comprising neutral, positive, and negative conditions. Statistical distributional methods based on delta plots [behavioral response time (RT) data] and quantile analysis (fNIRS data) were applied to evaluate the emotional interference effects. Results showed that both interference effects and disorder-specific (i.e., group-specific) effects could be detected, based on behavioral RTs, cortical hemodynamic signals (brain correlates), and heart rate variability (cardiac correlates). Subjects with high compared to low subclinical psychotic symptoms revealed significantly reduced amplitudes in dorsolateral prefrontal cortices (interference effect, p < 0.001) and middle temporal gyrus (disorder-specific group effect, p < 0.001), supported by behavioral and heart rate results. The present findings indicate that distributional analyses methods can support the detection of emotional interference effects in the emotional Stroop. The results suggested that subjects with high subclinical psychosis exhibit enhanced emotional interference effects. Based on these observations, subclinical psychosis may therefore prove to represent a valid extension of the clinical psychosis phenotype.

13.
J Biomed Opt ; 21(9): 091308, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27185106

RESUMEN

Pulse rate variability (PRV) can be extracted from functional near-infrared spectroscopy (fNIRS) (PRV(NIRS)) and photoplethysmography (PPG) (PRV(PPG)) signals. The present study compared the accuracy of simultaneously acquired PRV(NIRS) and PRV(PPG), and evaluated their different characterizations of the sympathetic (SNS) and parasympathetic (PSNS) autonomous nervous system activity. Ten healthy subjects were recorded during resting-state (RS) and respiratory challenges in two temperature conditions, i.e., room temperature (23°C) and cold temperature (4°C). PRV(NIRS) was recorded based on fNIRS measurement on the head, whereas PRV(PPG) was determined based on PPG measured at the finger. Accuracy between PRV(NIRS) and PRV(PPG), as assessed by cross-covariance and cross-sample entropy, demonstrated a high degree of correlation (r > 0.9), which was significantly reduced by respiration and cold temperature. Characterization of SNS and PSNS using frequency-domain, time-domain, and nonlinear methods showed that PRV(NIRS) provided significantly better information on increasing PSNS activity in response to respiration and cold temperature than PRV(PPG). The findings show that PRV(NIRS) may outperform PRV(PPG) under conditions in which respiration and temperature changes are present, and may, therefore, be advantageous in research and clinical settings, especially if characterization of the autonomous nervous system is desired.


Asunto(s)
Frecuencia Cardíaca/fisiología , Fotopletismografía/métodos , Procesamiento de Señales Asistido por Computador , Espectroscopía Infrarroja Corta/métodos , Adulto , Sistema Nervioso Autónomo/fisiología , Femenino , Humanos , Masculino , Curva ROC
14.
Disabil Rehabil Assist Technol ; 10(5): 385-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24730659

RESUMEN

PURPOSE: To evaluate feasibility and neurophysiological changes after virtual reality (VR)-based training of upper limb (UL) movements. METHOD: Single-case A-B-A-design with two male stroke patients (P1:67 y and 50 y, 3.5 and 3 y after onset) with UL motor impairments, 45-min therapy sessions 5×/week over 4 weeks. Patients facing screen, used bimanual data gloves to control virtual arms. Three applications trained bimanual reaching, grasping, hand opening. Assessments during 2-week baseline, weekly during intervention, at 3-month follow-up (FU): Goal Attainment Scale (GAS), Chedoke Arm and Hand Activity Inventory (CAHAI), Chedoke-McMaster Stroke Assessment (CMSA), Extended Barthel Index (EBI), Motor Activity Log (MAL). Functional magnetic resonance imaging scans (FMRI) before, immediately after treatment and at FU. RESULTS: P1 executed 5478 grasps (paretic arm). Improvements in CAHAI (+4) were maintained at FU. GAS changed to +1 post-test and +2 at FU. P2 executed 9835 grasps (paretic arm). CAHAI improvements (+13) were maintained at FU. GAS scores changed to -1 post-test and +1 at FU. MAL scores changed from 3.7 at pre-test to 5.5 post-test and 3.3 at FU. CONCLUSION: The VR-based intervention was feasible, safe, and intense. Adjustable application settings maintained training challenge and patient motivation. ADL-relevant UL functional improvements persisted at FU and were related to changed cortical activation patterns. Implications for Rehabilitation YouGrabber trains uni- and bimanual upper motor function. Its application is feasible, safe, and intense. The control of the virtual arms can be done in three main ways: (a) normal (b) virtual mirror therapy, or (c) virtual following. The mirroring feature provides an illusion of affected limb movements during the period when the affected upper limb (UL) is resting. The YouGrabber training led to ADL-relevant UL functional improvements that were still assessable 12 weeks after intervention finalization and were related to changed cortical activation patterns.


Asunto(s)
Simulación por Computador , Modalidades de Fisioterapia , Rehabilitación de Accidente Cerebrovascular , Extremidad Superior , Interfaz Usuario-Computador , Actividades Cotidianas , Enfermedad Crónica , Estudios de Factibilidad , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recuperación de la Función , Accidente Cerebrovascular/fisiopatología
15.
Behav Brain Res ; 270: 95-107, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24845305

RESUMEN

Simultaneous measurement of cortical and peripheral affective processing is relevant in many neuroscientific research fields. The aim was to investigate the influence of different affective task components on the coherence between cortical hemodynamic signals and peripheral autonomic skin potential signals. Seventeen healthy subjects performed four tasks, i.e. a finger-tapping task, a hyperventilation task, a working memory task and a risk-taking task. Cortical hemodynamic responses were measured using functional near-infrared spectroscopy (fNIRS). Peripheral skin conductance responses (SCRs) were assessed using electrodermal activity (EDA). Coherence between the fNIRS and the EDA time series was calculated using the S transform coherence (STC), a method that tests the temporal dynamics between two time series for consistent phase relationships and thus for a functional relationship. The following characteristics of fNIRS-EDA coherence were observed: (1) Simple motor performance was not a contributor to enhanced coherence, as revealed by the finger-tapping task. (2) Changes in respiration rate and/or heart rate acted as relevant contributors to enhanced coherence, as revealed by the hyperventilation task. (3) Working memory performance did not induce changes in coherence, (4) whereas risk-taking behavior was a significant contributor to enhanced coherence. (5) Based on all four tasks, we also observed that coherence may be subject to habituation or sensitization effects over the trial-to-trial course of a task. Increased fNIRS-EDA coherence may be an indicator of a psychophysiological link between the underlying cortical and peripheral affective systems. Our findings are relevant for several neuroscientific research areas seeking to evaluate the interplay between cortical and peripheral affective performance.


Asunto(s)
Circulación Cerebrovascular/fisiología , Hemodinámica/fisiología , Desempeño Psicomotor/fisiología , Sentido de Coherencia/fisiología , Espectroscopía Infrarroja Corta , Sistema Nervioso Simpático/fisiología , Adulto , Femenino , Respuesta Galvánica de la Piel/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Pruebas Neuropsicológicas , Frecuencia Respiratoria/fisiología , Asunción de Riesgos , Espectroscopía Infrarroja Corta/estadística & datos numéricos
16.
J Integr Neurosci ; 13(1): 121-42, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24738542

RESUMEN

The aim was to investigate the effect of mechanical pain stimulation at the lower back on hemodynamic and oxygenation changes in the prefrontal cortex (PFC) assessed by functional near-infrared spectroscopy (fNIRS) and on the partial pressure of end-tidal carbon dioxide ( PetCO 2) measured by capnography. 13 healthy subjects underwent three measurements (M) during pain stimulation using pressure pain threshold (PPT) at three locations, i.e., the processus spinosus at the level of L4 (M1) and the lumbar paravertebral muscles at the level of L1 on the left (M2) and the right (M3) side. Results showed that only in the M2 condition the pain stimulation elicited characteristic patterns consisting of (1) a fNIRS-derived decrease in oxy- and total hemoglobin concentration and tissue oxygen saturation, an increase in deoxy-hemoglobin concentration, (2) a decrease in the PetCO 2 response and (3) a decrease in coherence between fNIRS parameters and PetCO 2 responses in the respiratory frequency band (0.2-0.5 Hz). We discuss the comparison between M2 vs. M1 and M3, suggesting that the non-significant findings in the two latter measurements were most likely subject to effects of the different stimulated tissues, the stimulated locations and the stimulation order. We highlight that PetCO 2 is a crucial parameter for proper interpretation of fNIRS data in experimental protocols involving pain stimulation. Together, our data suggest that the combined fNIRS-capnography approach has potential for further development as pain monitoring method, such as for evaluating clinical pain treatment.


Asunto(s)
Capnografía , Hiperalgesia/fisiopatología , Dolor de la Región Lumbar/complicaciones , Umbral del Dolor/fisiología , Espectroscopía Infrarroja Corta , Adulto , Análisis de Varianza , Dióxido de Carbono/metabolismo , Circulación Cerebrovascular/fisiología , Femenino , Hemoglobinas/metabolismo , Humanos , Masculino , Dimensión del Dolor , Estimulación Física , Adulto Joven
17.
Brain Res ; 1557: 141-54, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24530267

RESUMEN

The study measured cortical hemodynamic signals and peripheral correlates of decision makers during a dynamic risky task, the Just One More task (JOM), in which the risky decision entails choosing whether to incrementally increase accumulated earnings at the risk of ruin (going bust ending up with nothing). Twenty subjects participated in multiple instantiations of this task in which the probability of ruin and size of the stakes varied. Physiological correlates were simultaneously quantified by functional near-infrared spectroscopy (fNIRS) over dorsolateral prefrontal cortex (DLPFC) and electrodermal activity (EDA). First, in the task decision phase (i.e., when subjects are contemplating options before making a choice) probability of ruin had a dissociating effect on fNIRS and EDA. fNIRS derived DLPFC hemodynamic signals reflected a subjective value signal, correlating positively with individual risk attitude. Contrary, EDA reflected the probability of ruin in terms of a common affective measure, irrespective of individuals׳ risk attitude. Second, during the task outcome phase (i.e., the time after subjects have made a choice and observed the outcomes) fNIRS and EDA revealed opposite patterns. While fNIRS derived DLPFC hemodynamic signals were larger in response to gains, EDA signals were larger in response to losses; both patterns were statistically independent of individual risk attitude. Lastly, fNIRS derived DLPFC hemodynamic signals in the decision phase correlated positively with the mean round earnings, providing a measure of the quality of the individual decision-making performance. Together with the positive correlation with individual risk attitude, our findings indicate that fNIRS signals, but not EDA, could be taken as a useful method for studying individual risk attitude and task performance in dynamic risky decision-making.


Asunto(s)
Actitud , Circulación Cerebrovascular/fisiología , Toma de Decisiones/fisiología , Respuesta Galvánica de la Piel/fisiología , Corteza Prefrontal/fisiología , Riesgo , Adulto , Retroalimentación Psicológica/fisiología , Femenino , Humanos , Individualidad , Modelos Lineales , Masculino , Pruebas Neuropsicológicas , Corteza Prefrontal/irrigación sanguínea , Probabilidad , Espectroscopía Infrarroja Corta , Análisis y Desempeño de Tareas
18.
Neuroimage ; 84: 833-42, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24096126

RESUMEN

Risk is an important factor impacting financial decisions. Risk can be processed objectively, e.g. as variance across possible outcomes of a choice option or subjectively, e.g. as value of that variance to a given individual. The aim of the present study was to test the potential of functional near-infrared spectroscopy (fNIRS) in assessing these different ways of processing risk while subjects decided between either high or low risk financial options or a safe (risk-free) option. For comparison we simultaneously measured electrodermal activity (EDA), a well-established method in decision-making research and a core measure of affective processes. FNIRS showed that lateral prefrontal cortex responses to high risk were enhanced relative to low risk only in risk-seeking individuals but reduced relative to low risk in risk-averse individuals. This is in-line with individual-specific risk processing reflecting the subjective value of risk. By contrast, EDA showed enhanced responses to high risk, independent of individual risk attitude, in-line with the notion of objective risk processing. The dissociation between the two measures arose even though they overall were equally sensitive to detect individual risk-related differences and even though there was an increased, risk attitude-independent, temporal coherence between the two measures during high-risk conditions. Our results suggest that hemodynamic responses in lateral prefrontal cortex as measured by fNIRS reflect the subjective value of risk, whereas EDA may index the objective amount of risk people are presented with. The findings suggest that fNIRS could be a useful method for studying risk behavior in financial decisions.


Asunto(s)
Mapeo Encefálico , Conducta de Elección , Corteza Prefrontal/fisiología , Asunción de Riesgos , Adulto , Mapeo Encefálico/métodos , Conducta de Elección/fisiología , Femenino , Humanos , Masculino , Espectroscopía Infrarroja Corta
19.
Brain Imaging Behav ; 8(4): 517-30, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24242358

RESUMEN

The study aimed to test the potential of functional near-infrared spectroscopy (fNIRS) in combination with electrodermal activity (EDA) in a decision paradigm by means of the Columbia card task (CCT). The CCT is a dynamic decision task characterized by assessing subjects' risk-taking via eliciting voluntary stopping points in a series of incrementally increasingly risky choices. Using the combined fNIRS-EDA approach, we aim to examine the hemodynamic and affective correlates of both decision and outcome responses during performance on the CCT. Twenty healthy subjects completed the Cold and Hot CCT version while fNIRS over prefrontal cortex and EDA were recorded. Results showed that (1) in the decision phase fNIRS revealed larger total hemoglobin concentration changes [tHb] in the Cold as compared to the Hot CCT, whereas EDA revealed an opposite pattern with larger skin conductance responses (SCRs) to the Hot as compared to the Cold CCT. (2) No significant [tHb] signals or SCRs were found in the outcome phase. (3) Coherence calculations between fNIRS and EDA in the heart rate frequency showed a significant increase during the Hot as compared to the Cold CCT. Our findings designate fNIRS as suitable tool for monitoring decision-making processes. The combination of fNIRS and EDA demonstrates the potential of simultaneously assessing the interaction between hemodynamic and affective responses which can provide additional information concerning the relationship between these two physiological systems for various research areas.


Asunto(s)
Afecto/fisiología , Encéfalo/fisiología , Toma de Decisiones/fisiología , Hemodinámica/fisiología , Corteza Prefrontal/fisiología , Asunción de Riesgos , Adulto , Circulación Cerebrovascular/fisiología , Femenino , Respuesta Galvánica de la Piel , Frecuencia Cardíaca/fisiología , Hemoglobinas/metabolismo , Humanos , Masculino , Pruebas Neuropsicológicas , Tiempo de Reacción , Procesamiento de Señales Asistido por Computador , Espectroscopía Infrarroja Corta , Encuestas y Cuestionarios
20.
Front Hum Neurosci ; 7: 813, 2013 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-24348362

RESUMEN

Since the first demonstration of how to simultaneously measure brain activity using functional magnetic resonance imaging (fMRI) on two subjects about 10 years ago, a new paradigm in neuroscience is emerging: measuring brain activity from two or more people simultaneously, termed "hyperscanning". The hyperscanning approach has the potential to reveal inter-personal brain mechanisms underlying interaction-mediated brain-to-brain coupling. These mechanisms are engaged during real social interactions, and cannot be captured using single-subject recordings. In particular, functional near-infrared imaging (fNIRI) hyperscanning is a promising new method, offering a cost-effective, easy to apply and reliable technology to measure inter-personal interactions in a natural context. In this short review we report on fNIRI hyperscanning studies published so far and summarize opportunities and challenges for future studies.

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