Affordances can invite behavior: Reconsidering the relationship between affordances and agency

The concept of agency has been central to ecological approaches to psychology. Gibson, one of the founders of this movement, made room for this concept by arguing against the mechanistic conceptions in psychology. In his view, the environment is not a collection of causes that pushes the animal around, but consist of action possibilities, which he coined affordances. In making their way in the world, animals regulate their behavior with respect to these possibilities. Reed later developed this ecological conception of agency, following Gibson in conceiving of affordances as action possibilities. However, drawing upon industrial design, architecture, and phenomenology, we argue that affordances are not mere action possibilities but that they can also invite behavior. We suggest a mutualist perspective on invitations, suggesting that they depend on the animal-environment relationship in multiple dimensions. The implications of this new conception of affordances for the ecological account of agency are explored.     

One hand, two objects: emergence of affordance in contexts

Studies on affordances typically focus on single objects. We investigated whether affordances are modulated by the context, defined by the relation between two objects and a hand. Participants were presented with pictures displaying two manipulable objects linked by a functional (knife-butter), a spatial (knife-coffee mug), or by no relation. They responded by pressing a key whether the objects were related or not. To determine if observing other's actions and understanding their goals would facilitate judgments, a hand was: (a) displayed near the objects; (b) grasping an object to use it; (c) grasping an object to manipulate/move it; (d) no hand was displayed. RTs were faster when objects were functionally rather than spatially related. Manipulation postures were the slowest in the functional context and functional postures were inhibited in the spatial context, probably due to mismatch between the inferred goal and the context. The absence of this interaction with foot responses instead of hands in Experiment 2 suggests that effects are due to motor simulation rather than to associations between context and hand-postures.     

Binocular vision enhances a rapidly evolving affordance priming effect: Behavioural and TMS evidence

Extensive research has suggested that simply viewing an object can automatically prime compatible actions for object manipulation, known as affordances. Here we explored the generation of covert motor plans afforded by real objects with precision (‘pinchable’) or whole-hand/power (‘graspable’) grip significance under different types of vision. In Experiment 1, participants viewed real object primes either monocularly or binocularly and responded to orthogonal auditory stimuli by making precision or power grips. Pinchable primes facilitated congruent precision grip responses relative to incongruent power grips, and vice versa for graspable primes, but only in the binocular vision condition. To examine the temporal evolution of the binocular affordance effect, participants in Experiment 2 always viewed the objects binocularly but made no responses, instead receiving a transcranial magnetic stimulation pulse over their primary motor cortex at three different times (150, 300, 450 ms) after prime onset. Motor evoked potentials (MEPs) recorded from a pinching muscle were selectively increased when subjects were primed with a pinchable object, whereas MEPs from a muscle associated with power grips were increased when viewing graspable stimuli. This interaction was obtained both 300 and 450 ms (but not 150 ms) after the visual onset of the prime, characterising for the first time the rapid development of binocular grip-specific affordances predicted by functional accounts of the affordance effect.     

Skill transfer,affordances and dexterity in different climbing environments

This study explored how skills in one region of a perceptual-motor landscape of performance, created in part by previous experience in rock climbing, can shape those that emerge in another region (ice climbing). Ten novices in rock climbing and five intermediate rock climbers were observed climbing an icefall. Locations of right and left ice tools and crampons were videotaped from a frontal camera. Inter-individual variability of upper and lower limb couplings and types of action regarding icefall properties were assessed by cluster hierarchical analysis, distinguishing three clusters. Pelvis vertical displacement, duration and number of pelvis pauses were also analyzed. Experienced rock climbers were grouped in the same cluster and showed the highest range and variability of limb angular locations and coordination patterns, the highest vertical displacement and the shortest pelvis plateaux durations. Non-fluent climbers (clusters 2 and 3) showed low range and variability of limb angular locations and coordination patterns. In particular, climbers of cluster 3 exhibited the lowest vertical displacement, the longest plateaux durations and the greatest ratio between tool swinging and definitive anchorage. Our results exemplified the positive influence of skills in rock climbing on ice climbing performance, facilitated by the detection of affordances from environmental properties.     

Re-conceptualizing Self,Speaker, and Body: Applying an Enactive and Conversation Analytic Approach to Selfhood and Cognition

In this article I review significant contributions to the subfield of Embodied Cognition that formulate an inclusive account of the body's role in cognitive processes. I argue that a reconceptualization of the mind–body problem must take into account some notion of the self as a nonlocalized, transient phenomenon that emerges through day-to-day interaction. Drawing on literature from epistemology, phenomenology, and Conversation Analysis, I aim to revise contributions that rely on essentialized notions of the self and speaker, in terms of an enactive and Conversation Analytic approach to selfhood and cognition.     

An information-based approach to action understanding

It has been proposed that the ability to make sense of other agents' behavior relies on the activation of internal mechanisms that map action perception onto action execution. In this study we explored the constraints on this ability introduced by eyeheight-scaled information in the optic array. Short and tall participants provided maximum overhead reaching judgments for themselves and another participant. Perceptual information was manipulated by changing the participants' optically specified eyeheight. Observers were modestly accurate in perceiving maximum overhead reach for themselves and for another actor whose action capabilities differed. Perceived maximum overhead reach increased for both self- and other-judgments when the perceiver's eyeheight was increased. The results suggest an important role of perceptual information that has gone unrecognized in existing accounts of action understanding and prediction.     

Inviting affordances and agency

Recently several authors have suggested that affordances are not mere possibilities for action but can also invite behavior. This reconceptualization of affordances asks for a reconsideration of the ecological approach to agency. After a portrayal of the role of agency in ecological psychology, we draw upon phenomenology to reveal what it means for an agent to be invited by affordances. We sketch a dynamical model of the animal-environment relationship that aims to do justice to this analysis. In the model, agency is conceptualized as the capacity to modulate the coupling strength with the environment—the agent can influence to what extent he or she is influenced by the different invitations. This account of agency keeps us far from the Cartesian idea that the agent imposes behavior. Indeed, by modulating the coupling strength, the agent simply alters the dynamics of the animal-environment interactions and thus the behavior that emerges.     

Exploring the effects of the Covid-19 pandemic on people's relationships with gardens

Gardens are places where science and art combine to create environments that often offer restorative and therapeutic experience to those who encounter them. During the Covid-19 pandemic, in the UK and elsewhere there has been a surge of interest in gardening. Public appreciation of gardens and other green spaces has grown and inequality of access to gardens and outdoor spaces has been extensively documented. Gardens are prevalent and of cultural significance in the UK, where their salutary properties have been documented for centuries. Yet people's relationships with gardens during the pandemic have been relatively underexplored in academia and were already under-researched prior to the pandemic's inception. This qualitative study investigates the relationships between people and gardens during the Covid-19 pandemic. Specifically, through thematic analysis based on in-depth interviews with 12 participants, it explores the effects that the pandemic had on people's relationships with gardens during an approximately 9-month period after the first national lockdown began in the UK. It places emphasis on health and wellbeing and garden design, using the concepts of agency and affordances as lenses through which to explore people's relationships with gardens. The results of this paper support others which have found people to be more supportive of nature-friendly garden design and to feel more connected with nature since the pandemic began.     

Situated language understanding as filtering perceived affordances

We introduce a computational theory of situated language understanding in which the meaning of words and utterances depends on the physical environment and the goals and plans of communication partners. According to the theory, concepts that ground linguistic meaning are neither internal nor external to language users, but instead span the objective-subjective boundary. To model the possible interactions between subject and object, the theory relies on the notion of perceived affordances: structured units of interaction that can be used for prediction at multiple levels of abstraction. Language understanding is treated as a process of filtering perceived affordances. The theory accounts for many aspects of the situated nature of human language use and provides a unified solution to a number of demands on any theory of language understanding including conceptual combination, prototypicality effects, and the generative nature of lexical items. To support the theory, we describe an implemented system that understands verbal commands situated in a virtual gaming environment. The implementation uses probabilistic hierarchical plan recognition to generate perceived affordances. The system has been evaluated on its ability to correctly interpret free-form spontaneous verbal commands recorded from unrehearsed game play between human players. The system is able to "step into the shoes" of human players and correctly respond to a broad range of verbal commands in which linguistic meaning depends on social and physical context. We quantitatively compare the system's predictions in response to direct player commands with the actions taken by human players and show generalization to unseen data across a range of situations and verbal constructions.     

Skill transfer specificity shapes perception and action under varying environmental constraints

Using an ecological dynamics framework, this study investigated the generality and specificity of skill transfer processes in organisation of perception and action using climbing as a task vehicle. Fluency of hip trajectory and orientation was assessed using normalized jerk coefficients exhibited by participants as they adapted perception and action under varying environmental constraints. Twelve recreational climbers were divided into two groups: one completing a 10-m high route on an indoor climbing wall; a second undertaking a 10-m high route on an icefall in a top-rope condition. We maintained the same level of difficulty between these two performance environments. An inertial measurement unit was attached each climber’s hips to collect 3D acceleration and 3D orientation data to compute jerk coefficient values. Video footage was used to record the ratio of exploratory/performatory movements. Results showed higher jerk coefficient values and number of exploratory movements for performance on the icefall route, perhaps due to greater functional complexity in perception and action required when climbing icefalls, which involves use of specific tools for anchorage. Findings demonstrated how individuals solve different motor problems, exploiting positive general transfer processes enabling participants to explore the pick-up of information for the perception of affordances specific to icefall climbing.