Naturalizing sense of agency with a hierarchical event-control approach

Feelings of responsibility and temporal binding: A comparison of two measures of the sense of agency

Temporal binding refers to a subjective shortening of the interval between an action and its perceptual consequences. Temporal binding has often been used by researchers to indirectly measure participants' sense of agency (SoA), or the subjective sense of causing something to happen. Other studies have proposed links between temporal binding and feelings of moral responsibility. The present study compared subjective interval estimates to feelings of responsibility in a between-subjects design (Exp 1) and a within-subjects design (Exp 2). Participants either estimated the interval between two events (two tones in the passive condition, or a keypress followed by a tone in active conditions) or rated their feeling of responsibility for the tone(s). Manipulations of participant involvement and choice impacted feelings of responsibility more than temporal estimates. Overall, the two dependent variables followed different patterns, suggesting subjective interval estimates may not be a reliable proxy for feelings of responsibility.

Cognitive load decreases the sense of agency during continuous action

The sense of agency that normally accompanies voluntary actions depends on a combination of sensory predictions and other inferences. For example, when people manipulate moving objects and rate their degree of control, control ratings are influenced by proximal correlations between motor commands and visual feedback as well as the overall success or failure of the action. The relative importance of sensory predictions vs. post hoc feedback may depend on the availability and perceived reliability of those cues, which is context dependent. The present study investigated how increasing cognitive load during a visuomotor tracking task influences the sense of agency, and whether cognitive load influences the extent to which control ratings depend on sensory predictions vs. post hoc feedback. In Experiments 1 and 2, participants performed a dual task that involved tracking a moving target using a joystick while rehearsing 3, 5, or 7 digits. Control ratings decreased as memory set size increased, even though set size had no significant effect on objective tracking error. Experiment 3 replicated this finding while also manipulating the favorability of feedback presented after each trial. Control ratings were correlated with post hoc feedback, but there was no significant interaction between feedback and cognitive load. These results suggest that sensorimotor predictions, performance feedback, and availability of working memory resources can all influence sense of agency. The hypothesis that people rely more on post hoc feedback to rate control when they are distracted was not supported.

Interactions among endogenous, exogenous, and agency-driven attentional selection mechanisms in interactive displays

Attentional selection is driven, in part, by a complex interplay between endogenous and exogenous cues. Recently, one's interactions with the physical world have also been shown to bias attention. Specifically, the sense of agency that arises when our actions cause predictable outcomes biases our attention toward those things which we control. We investigated how this agency-driven attentional bias interacts with simultaneously presented endogenous (words) and exogenous (color singletons) environmental cues. Participants controlled the movement of one object while others moved independently. In a subsequent search task, targets were either the previously controlled objects or not. Targets were also validly or invalidly cued. Both cue types influenced attention allocation. Endogenous cues and agency-driven attentional selection were independent and additive, indicating they are separable mechanisms of selection. In contrast, exogenous cues eliminated the effects of agency, indicating that perceptually salient environmental cues can override internally derived effects of agency. This is the first demonstration of a boundary condition on agency-driven selection.

Time and time again: a multi-scale hierarchical framework for time-consciousness and timing of cognition

Temporality and the feeling of 'now' is a fundamental property of consciousness. Different conceptualizations of time-consciousness have argued that both the content of our experiences and the representations of those experiences evolve in time, or neither have temporal extension, or only content does. Accounting for these different positions, we propose a nested hierarchical model of multiple timescales that accounts for findings on timing of cognition and phenomenology of temporal experience. This framework hierarchically combines the three major philosophical positions on time-consciousness (i.e. cinematic, extensional and retentional) and presents a common basis for temporal experience. We detail the properties of these hierarchical levels and speculate how they could coexist mechanistically. We also place several findings on timing and temporal experience at different levels in this hierarchy and show how they can be brought together. Finally, the framework is used to derive novel predictions for both timing of our experiences and time perception. The theoretical framework offers a novel dynamic space that can bring together sub-fields of cognitive science like perception, attention, action and consciousness research in understanding and describing our experiences both in and of time.

Measures of agency

The sense of agency is typically defined as the experience of controlling one’s own actions, and through them, changes in the external environment. It is often assumed that this experience is a single, unified construct that can be experimentally manipulated and measured in a variety of ways. In this article, we challenge this assumption. We argue that we should acknowledge four possible agency-related psychological constructs. Having a clear grasp of the possible constructs is important since experimental procedures are only able to target some but not all the possible constructs. The unacknowledged misalignment of the possible constructs of a sense of agency and the experimental procedures is a major theoretical and methodological obstacle to studying the sense of agency. Only if we recognize the nature of this obstacle will we be able to design the experimental paradigms that would enable us to study the responsible computational mechanisms.

Consciousness Without Content: A Look at Evidence and Prospects

Many traditions in the East have proposed that consciousness without content is possible and could be achieved with mental training. However, it is not clear whether such a state is possible given that intentionality is a critical property of mentality and consciousness in many theories of consciousness. A prominent recent attempt to account for such states of "minimal phenomenal experience" is the ascending reticular arousal system (ARAS) model, which proposes a specific type of non-conceptual representational content to address such a state. Consciousness without content can also be understood by studying related or similar states of minimal phenomenal experience and this paper discusses such findings from such states including dreamless sleep experience and their implications. One way to argue for the need for proposing consciousness without content is to locate a property of consciousness that would necessitate postulating it. A continuous state of consciousness without content may be needed to understand continuity of conscious experience. Finally, I discuss the implications of consciousness without content for current theories of consciousness.

A systematic evaluation of the evidence for perceptual control theory in tracking studies

Perceptual control theory (PCT) proposes that perceptual inputs are controlled to intentional 'reference' states by hierarchical negative feedback control, evidence for which comes from manual tracking experiments in humans. We reviewed these experiments to determine whether tracking is a process of perceptual control, and to assess the state-of-the-evidence for PCT. A systematic literature search was conducted of peer-review journal and book chapters in which tracking data were simulated with a PCT model (13 studies, 53 participants). We report a narrative review of these studies and a qualitative assessment of their methodological quality. We found evidence that individuals track to individual-specific endogenously-specified reference states and act against disturbances, and evidence that hierarchical PCT can simulate complex tracking. PCT's learning algorithm, reorganization, was not modelled. Limitations exist in the range of tracking conditions under which the PCT model has been tested. Future PCT research should apply the PCT methodology to identify control variables in real-world tasks and develop hierarchical PCT architectures for goal-oriented robotics to test the plausibility of PCT model-based action control.

Agency and responsibility over virtual movements controlled through different paradigms of brain-computer interface

KEY POINTS

Embodiment of a virtual body was induced and its movements were controlled by two different brain-computer interface (BCI) paradigms - one based on signals from sensorimotor versus one from visual cortical areas. BCI-control of movements engenders agency, but not equally for all paradigms. Cortical sensorimotor activation correlates with agency and responsibility. This has significant implications for neurological rehabilitation and neuroethics.

ABSTRACT

Agency is the attribution of an action to the self and is a prerequisite for experiencing responsibility over its consequences. Here we investigated agency and responsibility by studying the control of movements of an embodied avatar, via brain-computer interface (BCI) technology, in immersive virtual reality. After induction of virtual body ownership by visuomotor correlations, healthy participants performed a motor task with their virtual body. We compared the passive observation of the subject's 'own' virtual arm performing the task with (1) the control of the movement through activation of sensorimotor areas (motor imagery) and (2) the control of the movement through activation of visual areas (steady-state visually evoked potentials). The latter two conditions were carried out using a BCI and both shared the intention and the resulting action. We found that BCI-control of movements engenders the sense of agency, which is strongest for sensorimotor area activation. Furthermore, increased activity of sensorimotor areas, as measured using EEG, correlates with levels of agency and responsibility. We discuss the implications of these results for the neural basis of agency.

Individual Differences in Sensitivity to Visuomotor Discrepancies

This study explored whether sensitivity to visuomotor discrepancies, specifically the ability to detect and respond to loss of control over a moving object, is associated with other psychological traits and abilities. College-aged adults performed a computerized tracking task which involved keeping a cursor centered on a moving target using keyboard controls. On some trials, the cursor became unresponsive to participants' keypresses. Participants were instructed to immediately press the space bar if they noticed a loss of control. Response times (RTs) were measured. Additionally, participants completed a battery of behavioral and questionnaire-based tests with hypothesized relationships to the phenomenology of control, including measures of constructs such as locus of control, impulsiveness, need for cognition (NFC), and non-clinical schizotypy. Bivariate correlations between RTs to loss of control and high order cognitive and personality traits were not significant. However, a step-wise regression showed that better performance on the pursuit rotor task predicted faster RTs to loss of control while controlling for age, signal detection, and NFC. Results are discussed in relation to multifactorial models of the sense of agency.

Control Changes the Way We Look at the World

The feeling of control is a fundamental aspect of human experience and accompanies our voluntary actions all the time. However, how the sense of control interacts with wider perception, cognition, and behavior remains poorly understood. This study focused on how controlling an external object influences the allocation of attention. Experiment 1 examined attention to an object that is under a different level of control from the others. Participants searched for a target among multiple distractors on screen. All the distractors were partially under the participant's control (50% control level), and the search target was either under more or less control than the distractors. The results showed that, against this background of partial control, visual attention was attracted to an object only if it was more controlled than other available objects and not if it was less controlled. Experiment 2 examined attention allocation in contexts of either perfect control or no control over most of the objects. Specifically, the distractors were under either perfect (100%) control or no (0%) control, and the search target had one of six levels of control varying from 0% to 100%. When differences in control between the distractors and the target were small, visual attention was now more strongly drawn to search targets that were less controlled than distractors, rather than more controlled, suggesting attention to objects over which one might be losing control. Experiment 3 studied the events of losing or gaining control as opposed to the states of having or not having control. ERP measures showed that P300 amplitude proportionally encoded the magnitude of both increases and decreases in degree of control. However, losing control had more marked effects on P170 and P300 than gaining an equivalent degree of control, indicating high priority for efficiently detecting failures of control. Overall, our results suggest that controlled objects preferentially attract attention in uncontrolled environments. However, once control has been registered, the brain becomes highly sensitive to subsequent loss of control. Our findings point toward careful perceptual monitoring of degree of one's own agentic control over external objects. We suggest that control has intrinsic cognitive value because perceptual systems are organized to detect it and, once it has been acquired, to maintain it.

Measurement of the Perception of Control during Continuous Movement using Electroencephalography

“Sense of control” refers to the subjective feeling of control over external events. Numerous neuropsychological studies have investigated the neural basis of the sense of control during action performance; however, most previous studies have focused on responses to a single discrete action outcome rather than real-time processing of action-outcome sequences. In the present study, we aimed to identify whether certain patterns of brain activation are associated with the perceived control during continuous movement. We recorded electroencephalography (EEG) signals while participants continuously moved a right-handed mouse in an attempt to control multiple visual stimuli. When participants perceived a sense of control over the stimuli, we observed a positive potential approximately 550 ms after the onset of movement, while no similar potential was observed when participants reported a lack of control. The appearance of this potential was consistent with the time window of awareness of control in a behavioral test using the same task, and likely reflected the explicit allocation of attention to control. Moreover, we found that the alpha-mu rhythm, which is linked to sensorimotor processing, was significantly suppressed after participants came to a conclusion regarding the level of control, regardless of whether control or lack of control was perceived. In summary, our results suggest that the late positive potential after the onset of the movement and the suppression of alpha-mu rhythm can be used as markers of the perception of control during continuous action performance and feedback monitoring.

Multi-scale control influences sense of agency: Investigating intentional binding using event-control approach

Control exercised by humans through interactions with the environment is critical for sense of agency. Here, we investigate how control at multiple levels influence implicit sense of agency measured using intentional binding. Participants are asked to hit a moving target using a joystick with noisy control followed by an intentional binding task initiated by the target hitting action. Perceptual-motor level control was manipulated through noise in the joystick controller (experiment 1) and goal-level control in terms of feedback about successful hit (experiments 2a and 2b). In the first experiment, intentional binding increased with amount of joystick control only when goal was not achieved and independent otherwise suggesting that the two levels interact hierarchically. In the second experiment, the estimated duration was dependent on when participants knew about goal completion. The results are similar to those obtained with explicit measures of sense of agency indicating that multi-scale event control influences agency.

The experience of agency in human-computer interactions: a review

The sense of agency is the experience of controlling both one’s body and the external environment. Although the sense of agency has been studied extensively, there is a paucity of studies in applied “real-life” situations. One applied domain that seems highly relevant is human-computer-interaction (HCI), as an increasing number of our everyday agentive interactions involve technology. Indeed, HCI has long recognized the feeling of control as a key factor in how people experience interactions with technology. The aim of this review is to summarize and examine the possible links between sense of agency and understanding control in HCI. We explore the overlap between HCI and sense of agency for computer input modalities and system feedback, computer assistance, and joint actions between humans and computers. An overarching consideration is how agency research can inform HCI and vice versa. Finally, we discuss the potential ethical implications of personal responsibility in an ever-increasing society of technology users and intelligent machine interfaces.