Embodied Perception: A Proposal to Reconcile Affordance and Spatial Perception

The differential effects of task difficulty on the perception of passing distance and subsequent passing action in a field hockey push pass task

The aims of the study were to initially investigate whether the perceived distance of a field hockey push pass task was influenced by manipulating task difficulty (Experiment 1), and further, expanding on the research, whether perceptual biases would translate into the execution of a corresponding push pass action (Experiment 2). Based on predictions from the two-visual systems model, we hypothesized that the action-specific perceptual biases in distance perception would not translate into the control of movement. In Experiment 1, elite field hockey players estimated the distance from targets that differed in size before making push pass actions toward the target (i.e., the smaller targets being more difficult). Results showed that participants did estimate the perceived distance of the push pass task to be larger as a function of task difficulty. We found a similar result in Experiment 2, and in addition, manipulated the required outcome of the push-pass while measuring the speed of the push-pass and found that a perceptual bias did not translate into the execution of the actual push pass task (Experiment 2). In line with the action-specific account of perception, a perceptual bias arose that may assist in making adaptive action choices. However, consistent with the two-visual systems model, this perceptual bias did not affect subsequent control of movement, preventing it from becoming maladaptive. Implications for talent identification and development are briefly discussed.

Sense of Place, Fast and Slow: The Potential Contributions of Affordance Theory to Sense of Place

Over the past 40 years, the sense of place concept has been well-established across a range of applications and settings; however, most theoretical developments have “privileged the slow.” Evidence suggests that place attachments and place meanings are slow to evolve, sometimes not matching material or social reality (lag effects), and also tending to inhibit change. Here, we present some key blind spots in sense of place scholarship and then suggest how a reconsideration of sense of place as “fast” and “slow” could fill them. By this, we mean how direct and immediate perception–action processes presented in affordance theory (resulting in immediately perceived place meanings) can complement slower forms of social construction presented in sense of place scholarship. Key blind spots are that sense of place scholarship: (1) rarely accounts for sensory or immediately perceived meanings; (2) pays little attention to how place meanings are the joint product of attributes of environmental features and the attributes of the individual; and (3) assumes that the relationship between place attachment and behavior is linear and not constituted in dynamic relations among mind, culture, and environment. We show how these blind spots can begin to be addressed by reviewing key insights from affordance theory, and through the presentation of applied examples. We discuss future empirical research directions in terms of: (1) how sense of place is both perceived and socially constructed; (2) whether perceived and socially constructed dimensions of place can relate to one another when perceived meanings become unsituated; and (3) how place attachment may change over different stages of the life course based upon dynamic relationships between processes of perception–action and social construction. We conclude with insights into how processes of perception–action and social construction could be included in the design and management of urban landscapes.

Does grasping capacity influence object size estimates? It depends on the context

Linkenauger, Witt, and Proffitt (Journal of Experimental Psychology: Human Perception and Performance, 37(5), 1432–1441, 2011, Experiment 2) reported that right-handers estimated objects as smaller if they intended to grasp them in their right rather than their left hand. Based on the action-specific account, they argued that this scaling effect occurred because participants believed their right hand could grasp larger objects. However, Collier and Lawson (Journal of Experimental Psychology: Human Perception and Performance, 43(4), 749–769, 2017) failed to replicate this effect. Here, we investigated whether this discrepancy in results arose from demand characteristics. We investigated two forms of demand characteristics: altering responses following conscious hypothesis guessing (Experiments 1 and 2), and subtle influences of the experimental context (Experiment 3). We found no scaling effects when participants were given instructions which implied the expected outcome of the experiment (Experiment 1), but they were obtained when we used unrealistically explicit instructions which gave the exact prediction made by the action-specific account (Experiment 2). Scaling effects were also found using a context in which grasping capacity could seem relevant for size estimation (by asking participants about the perceived graspability of an object immediately before asking about its size on every trial, as was done in Linkenauger et al., 2011; Experiment 2). These results suggest that demand characteristics due to context effects could explain the scaling effects reported in Experiment 2 of Linkenauger et al. (2011), rather than either hypothesis guessing, or, as proposed by the action-specific account, a change in the perceived size of objects.

It's out of my hands! Grasping capacity may not influence perceived object size

Linkenauger, Witt, and Proffitt (2011) found that the perceived size of graspable objects was scaled by perceived grasping capacity. However, it is possible that this effect occurred because object size was estimated on the same trial as grasping capacity. This may have led to a conflation of estimates of perceived action capacity and spatial properties. In 5 experiments, we tested Linkenauger et al.’s claim that right-handed observers overestimate the grasping capacity of their right hand relative to their left hand, and that this, in turn, leads them to underestimate the size of objects to-be-grasped in their right hand relative to their left hand. We replicated the finding that right handers overestimate the size and grasping capacity of their right hand relative to their left hand. However, when estimates of object size and grasping capacity were made in separate tasks, objects grasped in the right hand were not underestimated relative to those grasped in the left hand. Further, when grasping capacity was physically restricted, observers appropriately recalibrated their perception of their maximum grasp but estimates of object size were unaffected. Our results suggest that changes in action capacity may not influence perceived object size if sources of conflation are controlled for.

The action-specific account of perception suggests that an observer’s capacity for action scales how the environment appears to them and, specifically, how they perceive its spatial properties. However, contrary to the predictions of this account, the results of the present studies suggest that perceived object size is not influenced by either actual or perceived grasping capacity. First, although right handers perceived their right hand to be both larger and to have a greater grasping capacity than their left hand, size estimates for an object were not influenced by which hand was used to grasp that object. Second, in a stronger manipulation, we reduced both the actual and the perceived grasping capacity of one hand by taping its fingers together. Despite this causing a substantial reduction in action capacity, it did not influence estimates of object size. These results show that action capacity and spatial properties can be perceived independently.

Acting is perceiving!

We challenge Firestone & Scholl's (F&S's) narrow conceptualization of what perception is and – most important – what it is for. Perception guides our (inter)actions with the environment, with attention ensuring that the actor is attuned to information relevant for action. We dispute F&S's misconceived (and counterfactual) view of perception as a module that functions independently from cognition, attention, and action.

The Relative Nature of Perception: A Response to Cañal-Bruland and van der Kamp (2015)

Cañal-Bruland and van der Kamp present an argument about the incommensurate relationship between affordance perception and spatial perception in a criticism of Proffitt and Linkenauger’s phenotypic approach to perception. Many of their criticisms are based on a difference in the interpretation of the core ideas underlying the phenotypic approach. The most important of these differences in interpretations concern fundamental assumptions about the nature of the perceptions of size and distance themselves. Extent perception must be relative to the organism; therefore, there can be no veridical perception of space. Also, we argue in the phenotypic approach that space perception is an emergent property of affordance perception; they are not different types of perceptions as Cañal-Bruland and van der Kamp presume. Third, affordance perception need not be perfectly accurate, just good enough. Additionally, affordance perception need not be dichotomous; this presumption likely originates in the methodology typically employed to study affordance perception. Finally, I agree with Cañal-Bruland and van der Kamp that joint research efforts will clarify and improve our understanding of these issues.