218 research outputs found
On the Origin of Interoception
Over the course of a century, the meaning of interoception has changed from the restrictive to the inclusive. In its inclusive sense, it bears relevance to every individual via its link to emotion, decision making, time-perception, health, pain, and various other areas of life. While the label for the perception of the body state changes over time, the need for an overarching concept remains. Many aspects can make any particular interoceptive sensation unique and distinct from any other interoceptive sensation. This can range from the sense of agency, to the physical cause of a sensation, the ontogenetic origin, the efferent innervation, and afferent pathways of the tissue involved amongst others. In its overarching meaning, interoception primarily is a product of the central nervous system, a construct based on an integration of various sources, not per se including afferent information. This paper proposes a definition of interoception as based on subjective experience, and pleas for the use of specific vocabulary in addressing the many aspects that contribute to it
Hemodynamic profiles of functional and dysfunctional forms of repetitive thinking
Background: The ability of the human brain to escape the here and now (mind wandering) can take functional (problem solving) and dysfunctional (perseverative cognition) routes. Although it has been proposed that only the latter may act as a mediator of the relationship between stress and cardiovascular disease, both functional and dysfunctional forms of repetitive thinking have been associated with blood pressure (BP) reactivity of the same magnitude. However, a similar BP reactivity may be caused by different physiological determinants, which may differ in their risk for cardiovascular pathology. Purpose: To examine the way (hemodynamic profile) and the extent (compensation deficit) to which total peripheral resistance and cardiac output compensate for each other in determining BP reactivity during functional and dysfunctional types of repetitive thinking. Methods: Fifty-six healthy participants randomly underwent a perseverative cognition, a mind wandering, and a problem solving induction, each followed by a 5-min recovery period while their cardiovascular parameters were continuously monitored. Results: Perseverative cognition and problem solving (but not mind wandering) elicited BP increases of similar magnitude. However, perseverative cognition was characterized by a more vascular (versus myocardial) profile compared to mind wandering and problem solving. As a consequence, BP recovery was impaired after perseverative cognition compared to the other two conditions. Conclusions: Given that high vascular resistance and delayed recovery are the hallmarks of hypertension the results suggest a potential mechanism through which perseverative cognition may act as a mediator in the relationship between stress and risk for developing precursors to cardiovascular disease
Switching Principal Component Analysis for Modeling Means and Covariance Changes Over Time
Many psychological theories predict that cognitions, affect, action tendencies, and other variables change across time in mean level as well as in covariance structure. Often such changes are rather abrupt, because they are caused by sudden events. To capture such changes, one may repeatedly measure the variables under study for a single individual and examine whether the resulting multivariate time series contains a number of phases with different means and covariance structures. The latter task is challenging, however. First, in many cases, it is unknown how many phases there are and when new phases start. Second, often a rather large number of variables is involved, complicating the interpretation of the covariance pattern within each phase. To take up this challenge, we present switching principal component analysis (PCA). Switching PCA detects phases of consecutive observations or time points (in single subject data) with similar means and/or covariation structures, and performs a PCA per phase to yield insight into its covariance structure. An algorithm for fitting switching PCA solutions as well as a model selection procedure are presented and evaluated in a simulation study. Finally, we analyze empirical data on cardiorespiratory recordings
Respiratory modulation of intensity ratings and psychomotor response times to acoustic startle stimuli
Respiratory interoception may play an important role in the perception of respiratory symptoms in pulmonary diseases. As the respiratory cycle affects startle eye blink responses, startle modulation may be used to assess visceral-afferent signals from the respiratory system. To ascertain the potential impact of brainstem-relayed signals on cortical processes, we investigated whether this pre-attentive respiratory modulation of startle (RMS) effect is also reflected in the modulation of higher cognitive, evaluative processing of the startle stimulus. Twenty-nine healthy volunteers received 80 acoustic startle stimuli (100 or 105 dB(A); 50 ms), which were presented at end and mid inspiration and expiration, while performing a paced breathing task (0.25 Hz). Participants first responded to the startle probes by 'as fast as possible' button pushes and then rated the perceived intensity of the stimuli. Psychomotor response time was divided into 'reaction time' (RT; from stimulus onset to home button release; represents stimulus evaluation) and 'movement time' time (MT; from home button release to target button press). Intensity judgements were higher and RTs accelerated during mid expiration. No effect of respiratory cycle phase was found on eye blink responses and MTs. We conclude that respiratory cycle phase affects higher cognitive, attentional processing of startle stimuli
The Effects of Repeated Dyspnea Exposure on Response Inhibition
In order to treat dyspnea (=breathlessness) successfully, response inhibition (RI) as a major form of self-regulation is a premise. This is supported by research showing that self-regulation is associated with beneficial behavioral changes supporting treatment success in patients. Recent research showed that dyspnea has an impairing effect on RI, but the effects of repeated dyspnea exposure on RI remain unknown. Therefore, the present study tested the effects of repeated resistive load-induced dyspnea on RI over a 5-day period. Healthy volunteers (n = 34) performed the standard version of the Stroop task during baseline and dyspnea conditions on the first and fifth testing day and underwent an additional dyspnea exposure phase on each testing day. Variables of interest to investigate RI were reaction time, accuracy as well as the event-related potentials late positive complex (LPC) and N400 in the electroencephalogram. Reduced accuracy for incongruent compared to congruent stimuli during the dyspnea condition on the first testing day were found (p < 0.001). This was paralleled by a reduced LPC and an increased N400 for incongruent stimuli during the induction of dyspnea (p < 0.05). After undergoing dyspnea exposure, habituation of dyspnea intensity was evident. Importantly, on the fifth testing day, no differences between baseline, and dyspnea conditions were found for behavioral and electrophysiological measures of RI. These findings demonstrate that the impairing effect of dyspnea on RI disappeared after repeated dyspnea exposure in healthy participants. Translated to a clinical sample, it might cautiously be suggested that dyspnea exposure such as dyspnea perceived during physical exercise could reduce the impairing effect of dyspnea on RI which might have the potential to help increase self-regulation abilities and subsequent treatment efforts in dyspneic patients
Делистинг как инструмент управления ценностью для акционеров
Цель: выделить драйверы, влияющие на решение о делистинге, с целью построения инвестиционной стратегии для потенциальных бенефициаров сделок ухода публичных компаний с биржи Задачи: 1) Провести теоретический обзор проблемы исследования с идентификацией природы и принципов феномена делистинга; 2) Проанализировать главные причины для добровольного делистинга; 3) Провести обзор процедур ухода с биржи; 4) Провести эмпирическое исследование относительно оценки влияния независимы переменных на решение о делистинге; 5) Предложить рекомендации для менеджеров и индивидуальных инвесторов; 6) Сделать общее заключение, суммируя результаты и подтверждая достижение цели. Основные результаты: Рекомендации сформированы в таблицы для распространения между определенными целевыми группами. Данные материалы считаются удобными в использовании и не требуют глубокого профессионального погружения в вопросы феномена делистинга. Предложена инвестиционная стратегия для бенефициаров сделок ухода публичных компаний с биржи.Goal: to identify drivers of delisting process in order to build investment strategy for potential beneficiaries of the going private transactions Objectives: 7) To make the theoretical overview of the research problem with identification of nature and principles related to delisting phenomena; 8) To analyze the main reasons for voluntary delisting; 9) To overview procedures for going private transactions; 10) To conduct an empirical study regarding evaluation of variables influenced the decision to delist; 11) To provide the recommendations applicable for managers and individuals; 12) To make a general conclusion on the research paper summing up all the results and confirming of achievement the stated goal. Main results: The recommendations are formed in tables for distribution among particular target groups and considered to be user-friendly and adopted for different level of diving into voluntary delisting topic. The managerial implications suggest built investment strategy for those who are interested in obtaining benefits from public-to-private transactions
Large-scale wearable data reveal digital phenotypes for daily-life stress detection
Physiological signals have shown to be reliable indicators of stress in laboratory studies, yet large-scale ambulatory validation is lacking. We present a large-scale cross-sectional study for ambulatory stress detection, consisting of 1002 subjects, containing subjects' demographics, baseline psychological information, and five consecutive days of free-living physiological and contextual measurements, collected through wearable devices and smartphones. This dataset represents a healthy population, showing associations between wearable physiological signals and self-reported daily-life stress. Using a data-driven approach, we identified digital phenotypes characterized by self-reported poor health indicators and high depression, anxiety and stress scores that are associated with blunted physiological responses to stress. These results emphasize the need for large-scale collections of multi-sensor data, to build personalized stress models for precision medicine
Resting Heart Rate Variability Predicts Safety Learning and Fear Extinction in an Interoceptive Fear Conditioning Paradigm
This study aimed to investigate whether interindividual differences in autonomic inhibitory control predict safety learning
and fear extinction in an interoceptive fear conditioning paradigm. Data from a previously reported study (N = 40) were
extended (N = 17) and re-analyzed to test whether healthy participants’ resting heart rate variability (HRV) - a proxy of
cardiac vagal tone - predicts learning performance. The conditioned stimulus (CS) was a slight sensation of breathlessness
induced by a flow resistor, the unconditioned stimulus (US) was an aversive short-lasting suffocation experience induced by
a complete occlusion of the breathing circuitry. During acquisition, the paired group received 6 paired CS-US presentations;
the control group received 6 explicitly unpaired CS-US presentations. In the extinction phase, both groups were exposed to
6 CS-only presentations. Measures included startle blink EMG, skin conductance responses (SCR) and US-expectancy ratings.
Resting HRV significantly predicted the startle blink EMG learning curves both during acquisition and extinction. In the
unpaired group, higher levels of HRV at rest predicted safety learning to the CS during acquisition. In the paired group,
higher levels of HRV were associated with better extinction. Our findings suggest that the strength or integrity of prefrontal
inhibitory mechanisms involved in safety- and extinction learning can be indexed by HRV at rest
Startle responding in the context of visceral pain
This study aimed to investigate affective modulation of eye blink startle by aversive visceral stimulation. Startle blink EMG responses were measured in 31 healthy participants receiving painful, intermittent balloon distentions in the distal esophagus during 4 blocks (positive, negative, neutral or no pictures), and compared with startles during 3 ‘safe’ blocks without esophageal stimulations (positive, negative or neutral emotional pictures). Women showed enhanced startle during blocks with distentions (as compared with ‘safe’ blocks), both when the balloon was in inflated and deflated states, suggesting that fear and/or expectations may have played a role. Men's startle did not differ between distention and non-distention blocks. In this particular study context affective picture viewing did not further impose any effect on startle eye blink responses. The current results may contribute to a better understanding of emotional reactions to aversive interoceptive stimulation
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