Cardiac concomitants of performance monitoring: context dependence and individual differences

Heart is deceitful above all things: Threat expectancy induces the illusory perception of increased heartrate

It has been suggested that our perception of the internal milieu, or the body's internal state, is shaped by our beliefs and previous knowledge about the body's expected state, rather than being solely based on actual interoceptive experiences. This study investigated whether heartbeat perception could be illusorily distorted towards prior subjective beliefs, such that threat expectations suffice to induce a misperception of heartbeat frequency. Participants were instructed to focus on their cardiac activity and report their heartbeat, either tapping along to it (Experiment 1) or silently counting (Experiment 2) while ECG was recorded. While completing this task, different cues provided valid predictive information about the intensity of an upcoming cutaneous stimulation (high- vs. low- pain). Results showed that participants expected a heart rate increase over the anticipation of high- vs. low-pain stimuli and that this belief was perceptually instantiated, as suggested by their interoceptive reports. Importantly, the perceived increase was not mirrored by the real heart rate. Perceptual modulations were absent when participants executed the same task but with an exteroceptive stimulus (Experiment 3). The findings reveal, for the first time, an interoceptive illusion of increased heartbeats elicited by threat expectancy and shed new light on interoceptive processes through the lenses of Bayesian predictive processes, providing tantalizing insights into how such illusory phenomena may intersect with the recognition and regulation of people's internal states.

Positive affect and heart rate variability: a dynamic analysis

Traditional survey methods can provide noisy data arising from recall, memory and other biases. Technological advances (particularly in neuroscience) are opening new ways of monitoring physiological processes through non-intrusive means. Such dense continuous data provide new and fruitful avenues for complementing self-reported data with a better understanding of human dynamics and human interactions. In this study, we use a survey to collect positive affect (feelings) data from more than 300 individuals over a period of 24 h, and at the same time, map their core activities (5000 recorded activities in total) with measurements of their heart rate variability (HRV). Our results indicate a robust correlation between the HRV measurements and self-reported affect. By drawing on the neuroscience and wellbeing literature we show that dynamic HRV results are what we expect for positive affect, particularly when performing activities like sleep, travel, work, exercise and eating. This research provides new insights into how to collect HRV data, model and interpret it.

Interoceptive rhythms in the brain

Sensing internal bodily signals, or interoception, is fundamental to maintain life. However, interoception should not be viewed as an isolated domain, as it interacts with exteroception, cognition and action to ensure the integrity of the organism. Focusing on cardiac, respiratory and gastric rhythms, we review evidence that interoception is anatomically and functionally intertwined with the processing of signals from the external environment. Interactions arise at all stages, from the peripheral transduction of interoceptive signals to sensory processing and cortical integration, in a network that extends beyond core interoceptive regions. Interoceptive rhythms contribute to functions ranging from perceptual detection up to sense of self, or conversely compete with external inputs. Renewed interest in interoception revives long-standing issues on how the brain integrates and coordinates information in distributed regions, by means of oscillatory synchrony, predictive coding or multisensory integration. Considering interoception and exteroception in the same framework paves the way for biological modes of information processing specific to living organisms.

The functional role of cardiac activity in perception and action

SKORA, L.I., J.J.A. LIVERMORE and K. Roelofs. The functional role of cardiac activity in perception and action. NEUROSCI BIOBEHAV REV X(X) XXX-XXX, 2022. Patterns of cardiac activity continuously vary with environmental demands, accelerating or decelerating depending on circumstances. Simultaneously, cardiac cycle affects a host of higher-order processes, where systolic baroreceptor activation largely impairs processing. However, a unified functional perspective on the role of cardiac signal in perception and action has been lacking. Here, we combine the existing strands of literature and use threat-, anticipation-, and error-related cardiac deceleration to show that deceleration is an adaptive mechanism dynamically attenuating the baroreceptor signal associated with each heartbeat to minimise its impact on exteroceptive processing. This mechanism allows to enhance attention afforded to external signal and prepare an appropriate course of action. Conversely, acceleration is associated with a reduced need to attend externally, enhanced action tendencies and behavioural readjustment. This novel account demonstrates that dynamic adjustments in heart rate serve the purpose of regulating the level of precision afforded to internal versus external evidence in order to optimise perception and action. This highlights that the importance of cardiac signal in adaptive behaviour lies in its dynamic regulation.

Awareness is required for autonomic performance monitoring in instrumental learning: Evidence from cardiac activity

Performance monitoring is a vital aspect of successful learning and decision‐making. Performance errors are reflected in the autonomic nervous system, indicating the need for behavioral adjustment. As part of this response, errors cause a pronounced deceleration in heart rate, compared to correct decisions, and precede explicit awareness of stimulus–response outcome contingencies. However, it is unknown whether those signals are present and able to inform instrumental learning without stimulus awareness, where explicit performance monitoring is disabled. With mixed evidence for unconscious instrumental learning, determining the presence or absence of autonomic signatures of performance monitoring can shed light on its feasibility. Here, we employed an unconscious instrumental conditioning task, where successful learning is evidenced by increased approach responses to visually masked rewarding stimuli, and avoidance of punishing stimuli. An electrocardiogram (ECG) assessed cardiac activity throughout the learning process. Natural fluctuations of awareness under masking permitted us to contrast learning and cardiac deceleration for trials with, versus without, conscious stimulus awareness. Our results demonstrate that on trials where participants did not consciously perceive the stimulus, there was no differentiation in cardiac response between rewarding and punishing feedback, indicating an absence of performance monitoring. In contrast, consciously perceived stimuli elicited the expected error‐related deceleration. This result suggests that, in unconscious instrumental learning, the brain might be unable to acquire knowledge of stimulus values to guide correct instrumental choices. This evidence provides support for the notion that consciousness might be required for flexible adaptive behavior, and that this may be mediated through bodily signals.

Performance monitoring is vital to successful learning. We provide novel evidence that autonomic performance monitoring, indexed by cardiac deceleration, is only engaged in conscious, but not unconscious, instrumental learning. This result provides support for the notion that consciousness is required for flexible adaptive behaviour, and that this relationship may be mediated by bodily signals.

Autonomic responses to choice outcomes: Links to task performance and reinforcement-learning parameters

Previous work has shown that autonomic responses to choice feedback can predict subsequent decision-making. In this study, we tested whether skin conductance responses (SCRs) and heart rate (HR) decelerations following the presentation of choice outcomes predict Iowa Gambling Task performance in nonclinical participants (n = 64). We also examined how these signals related to parameters of a reinforcement-learning (RL) model. Feedback SCRs and HR decelerations were greater following outcomes that included losses and choices from the bad decks defined by their negative expected value. In addition, SCRs predicted task performance. A hierarchical Bayesian RL model indicated that greater feedback SCR for the bad decks compared to good decks was associated with stronger loss aversion and a lower learning rate, both of which predicted higher performance. These results suggest that feedback-related SCRs are linked to individual differences in outcome evaluation and learning processes that guide reinforcement-learning.

Cardiac Concomitants of Feedback and Prediction Error Processing in Reinforcement Learning

Successful learning hinges on the evaluation of positive and negative feedback. We assessed differential learning from reward and punishment in a monetary reinforcement learning paradigm, together with cardiac concomitants of positive and negative feedback processing. On the behavioral level, learning from reward resulted in more advantageous behavior than learning from punishment, suggesting a differential impact of reward and punishment on successful feedback-based learning. On the autonomic level, learning and feedback processing were closely mirrored by phasic cardiac responses on a trial-by-trial basis: (1) Negative feedback was accompanied by faster and prolonged heart rate deceleration compared to positive feedback. (2) Cardiac responses shifted from feedback presentation at the beginning of learning to stimulus presentation later on. (3) Most importantly, the strength of phasic cardiac responses to the presentation of feedback correlated with the strength of prediction error signals that alert the learner to the necessity for behavioral adaptation. Considering participants' weight status and gender revealed obesity-related deficits in learning to avoid negative consequences and less consistent behavioral adaptation in women compared to men. In sum, our results provide strong new evidence for the notion that during learning phasic cardiac responses reflect an internal value and feedback monitoring system that is sensitive to the violation of performance-based expectations. Moreover, inter-individual differences in weight status and gender may affect both behavioral and autonomic responses in reinforcement-based learning.

Impact of task-related changes in heart rate on estimation of hemodynamic response and model fit

The blood oxygen level dependent (BOLD) signal, as measured using functional magnetic resonance imaging (fMRI), is widely used as a proxy for changes in neural activity in the brain. Physiological variables such as heart rate (HR) and respiratory variation (RV) affect the BOLD signal in a way that may interfere with the estimation and detection of true task-related neural activity. This interference is of particular concern when these variables themselves show task-related modulations. We first establish that a simple movement task reliably induces a change in HR but not RV. In group data, the effect of HR on the BOLD response was larger and more widespread throughout the brain than were the effects of RV or phase regressors. The inclusion of HR regressors, but not RV or phase regressors, had a small but reliable effect on the estimated hemodynamic response function (HRF) in M1 and the cerebellum. We next asked whether the inclusion of a nested set of physiological regressors combining phase, RV, and HR significantly improved the model fit in individual participants' data sets. There was a significant improvement from HR correction in M1 for the greatest number of participants, followed by RV and phase correction. These improvements were more modest in the cerebellum. These results indicate that accounting for task-related modulation of physiological variables can improve the detection and estimation of true neural effects of interest.

Heartbeat and economic decisions: observing mental stress among proposers and responders in the ultimatum bargaining game

The ultimatum bargaining game (UBG), a widely used method in experimental economics, clearly demonstrates that motives other than pure monetary reward play a role in human economic decision making. In this study, we explore the behaviour and physiological reactions of both responders and proposers in an ultimatum bargaining game using heart rate variability (HRV), a small and nonintrusive technology that allows observation of both sides of an interaction in a normal experimental economics laboratory environment. We find that low offers by a proposer cause signs of mental stress in both the proposer and the responder; that is, both exhibit high ratios of low to high frequency activity in the HRV spectrum.

Encoding of sensory prediction errors in the human cerebellum

A central tenet of motor neuroscience is that the cerebellum learns from sensory prediction errors. Surprisingly, neuroimaging studies have not revealed definitive signatures of error processing in the cerebellum. Furthermore, neurophysiologic studies suggest an asymmetry, such that the cerebellum may encode errors arising from unexpected sensory events, but not errors reflecting the omission of expected stimuli. We conducted an imaging study to compare the cerebellar response to these two types of errors. Participants made fast out-and-back reaching movements, aiming either for an object that delivered a force pulse if intersected or for a gap between two objects, either of which delivered a force pulse if intersected. Errors (missing the target) could therefore be signaled either through the presence or absence of a force pulse. In an initial analysis, the cerebellar BOLD response was smaller on trials with errors compared with trials without errors. However, we also observed an error-related decrease in heart rate. After correcting for variation in heart rate, increased activation during error trials was observed in the hand area of lobules V and VI. This effect was similar for the two error types. The results provide evidence for the encoding of errors resulting from either the unexpected presence or unexpected absence of sensory stimulation in the human cerebellum.

Dissociation between medial frontal negativity and cardiac responses in the ultimatum game: Effects of offer size and fairness

In the present study, we examined the role of fairness and offer size on brain and cardiac responses in the ultimatum game (UG). Twenty healthy volunteers played the role of responder in a computerized version of the UG in which the fairness and size of the offers were systematically varied. Both fairness and size of the offer influenced the acceptance rates in a predictable way, leading to fewer accepted unfair and low offers. Only unfair high, but not unfair low offers were accompanied by a medial frontal negativity. An unexpected stronger cardiac deceleration to fairer offers was found, which was not affected by the size of the offers. Cardiac and electrocortical measures showed a different relation with performance, and both measures were correlated only modestly. This dissociation between cardiac responses and brain potentials is discussed in terms of a possible differential sensitivity to effects of stimulus probability and violation of the social rules.

Place your bets: psychophysiological correlates of decision-making under risk

Emotions and their psychophysiological correlates are thought to play an important role in decision-making under risk. We used a novel gambling task to measure psychophysiological responses during selection of explicitly presented risky options and feedback processing. Active-choice trials, in which the participant had to select the size of bet, were compared to fixed-bet, no-choice trials. We further tested how the chances of winning and bet size affected choice behavior and psychophysiological arousal. Individual differences in impulsive and risk-taking traits were assessed. The behavioral results showed sensitivity to the choice requirement and to the chances of winning: Participants were faster to make a response on no-choice trials and when the chances of winning were high. In active-choice trials, electrodermal activity (EDA) increased with bet size during both selection and processing of losses. Cardiac responses were sensitive to choice uncertainty: Stronger selection-related heart rate (HR) decelerations were observed in trials with lower chances of winning, particularly on active-choice trials. Finally, betting behavior and psychophysiological responsiveness were moderately correlated with self-reported impulsivity-related traits. In conclusion, we demonstrate that psychophysiological arousal covaries with risk-sensitive decision-making outside of a learning context. Our results further highlight the differential sensitivities of EDA and HR to psychological features of the decision scenario.

Cardiac and Electrophysiological Responses to Valid and Invalid Feedback in a Time-Estimation Task

This study investigated the cardiac and electrophysiological responses to feedback in a time-estimation task in which feedback-validity was manipulated. Participants across a wide age range had to produce 1 s intervals followed by positive and negative feedback that was valid or invalid (i.e., related or unrelated to the preceding time estimate). Performance results showed that they processed the information provided by the feedback. Negative feedback was associated with a transient cardiac slowing only when feedback was valid. Correct adjustments after valid negative feedback were associated with a more pronounced cardiac slowing. Validity did not affect the feedback-related negativity (FRN), except when remedial action was taken into account. The FRN and cardiac response to feedback decreased with advancing age, but performance did not. The current pattern of findings was interpreted to suggest that the FRN and cardiac response signal “alert” and that the cardiac response, but not the FRN, is implicated in the mechanisms invoked in remedial action.

Impaired decision making in oppositional defiant disorder related to altered psychophysiological responses to reinforcement

BACKGROUND

When making decisions, children with oppositional defiant disorder (ODD) are thought to focus on reward and ignore penalty. This is suggested to be associated with a state of low psychophysiological arousal.

METHODS

This study investigates decision making in 18 children with oppositional defiant disorder and 24 typically developing control subjects. Children were required to choose between three alternatives that carried either frequent small rewards and occasional small penalties (advantageous), frequent large rewards and increasing penalties (seductive), or frequent small rewards and increasing penalties (disadvantageous). Penalties in the seductive and disadvantageous alternatives increased either in frequency or magnitude in two conditions. Heart rate (HR) and skin conductance responses to reinforcement were obtained.

RESULTS

In the magnitude condition, children with ODD showed an increased preference for the seductive alternative (carrying large rewards); this was not observed in the frequency condition. Children with ODD, compared with typically developing children, displayed greater HR reactivity to reward (more HR deceleration) and smaller HR reactivity to penalty. Correlation analyses showed that decreased HR responses to penalty were related to an increased preference for large rewards. No group differences were observed in skin conductance responses to reward or penalty.

CONCLUSIONS

The findings suggest that an increased preference for large rewards in children with ODD is related to a reduced cardiac reactivity to aversive stimuli. This confirms notions of impaired decision making and altered reinforcement sensitivity in children with ODD and adds to the literature linking altered autonomic control to antisocial behavior.

Developmental changes and individual differences in risk and perspective taking in adolescence

Despite the assumed prevalence of risk-taking behavior in adolescence, the laboratory evidence of risk taking remains scarce, and the individual variation poorly understood. Drawing from neuroscience studies, we tested whether risk and reward orientation are influenced by the perspective that adolescents take when making risky decisions. Perspective taking was manipulated by cuing participants prior to each choice whether the decision was made for “self,” or from the perspective of an “other” (the experimenter in Experiment 1; a hypothetical peer in Experiment 2). In Experiment 1, we show a developmental decrease in risk-taking behavior across different stages of adolescence. In addition, all age groups made fewer risky choices for the experimenter, but the difference between self and other was larger in early adolescence. In Experiment 2, we show that high sensation-seeking (SS) adolescents make more risky choices than low SS adolescents, but both groups make a similar differentiation for other individuals (low risk-taking or high risk-taking peers). Together, the results show that younger adolescents and high SS adolescents make more risky choices for themselves, but can appreciate that others may make fewer risky choices. The developmental change toward more rational decisions versus emotional, impulsive decisions may reflect, in part, more efficient integration of others’ perspectives into one's decision making. These developmental results are discussed regarding brain systems important for risk taking and perspective taking.

Acute tryptophan depletion in healthy males attenuates phasic cardiac slowing but does not affect electro-cortical response to negative feedback

RATIONALE

Recent studies have shown that serotonin might be involved in performance monitoring, although the results have been inconclusive. Inconsistent results might be related to the type of pharmacological manipulation and the used behavioral and physiological measures.

OBJECTIVES

The present study aimed at further specifying the role of serotonin in performance monitoring.

MATERIALS AND METHODS

The effect of serotonin on performance monitoring was studied by using acute tryptophan depletion (ATD), a well-known method to transiently lower central serotonin levels. Twenty healthy male volunteers performed a time-estimation task and their event-related brain potential (ERP), behavioral, and cardiac responses to feedback stimuli were measured. Furthermore, subjective mood and amino-acid levels were determined.

RESULTS

As expected, ATD did not affect mood and lowered tryptophan levels. ATD attenuated cardiac slowing to negative feedback but did not affect responses to positive feedback, ERPs, and performance measures.

CONCLUSIONS

The data point in the direction of a dissociation between cardiac and electro-cortical responses. Cardiac responses appear to be more sensitive to changes in serotonin metabolism and appear to reflect different aspects of the feedback stimulus. The phasic cardiac response appears to be an important measure that provides additional information about the impact of feedback stimuli and serotonergic functioning.

Heart rate and reinforcement sensitivity in ADHD

BACKGROUND

Both theoretical and clinical accounts of attention-deficit/hyperactivity disorder (ADHD) implicate a dysfunctional reinforcement system. This study investigated heart rate parameters in response to feedback associated with reward and response cost in ADHD children and controls aged 8 to 12.

METHODS

Heart rate responses (HRRs) following feedback and heart rate variability (HRV) in the low frequency band (.04-.08 Hz), a measure of mental effort, were calculated during a time production paradigm. Performance was coupled to monetary gain, loss or feedback-only in a cross-over design.

RESULTS

Children with ADHD exhibited smaller HRRs to feedback compared to controls. HRV of children with ADHD decreased when performance was coupled to reward or response cost compared to feedback-only. HRV of controls was similar across conditions.

CONCLUSIONS

Children with ADHD were characterised by (a) possible abnormalities in feedback monitoring and (b) motivational deficits, when no external reinforcement is present.

A heart rate analysis of developmental change in feedback processing and rule shifting from childhood to early adulthood

Over the course of development, the ability to switch between different tasks on the basis of feedback cues increases profoundly, but the role of performance monitoring remains unclear. Heart rate indexes can provide critical information about how individuals monitor feedback cues indicating that performance should be adjusted. In this study, children of three age groups (8-10, 12-14, and 16-18 years) performed a rule change task in which sorting rules needed to be detected following positive or negative feedback. The number of perseverative errors was lower for 16- to 18-year-olds than for 8- to 10-year-olds, and 12- to 14-year-olds performed at an intermediate level. Consistent with previous findings, heart rate slowed following feedback indicating a rule change, and the magnitude of slowing was similar for all age groups. Thus, 8- to 10-year-olds are already able to analyze feedback cues. In contrast, 12- to 14-year-olds and 16- to 18-year-olds, but not 8- to 10-year-olds, showed heart rate slowing following performance errors, suggesting that with age children are increasingly able to monitor their performance online. Performance monitoring may therefore be an important contributor to set-shifting ability.

Neurobiology of decision-making: quo vadis?

Decision-making is an important aspect of daily life. Moreover, dysfunctions of decision-making play a critical role in a number of neuropsychiatric disorders. Several important research groups have contributed a diverse set of approaches to study decision-making and its underlying neurobiology. Insights from these studies may provide important directions for future research in this area.