Understanding others by doing things together: an enactive account

Enactivists claim that social cognition is constituted by interactive processes and even more radically that there is ‘no observation without interaction’. Nevertheless, the notion of interaction at the core of the account has not yet being characterized in a way that makes good the claim that interactions actually constitute social understanding rather than merely facilitating or causally contributing to it. This paper seeks to complement the enactivist approach by offering an account of basic joint action that involves and brings with it basic forms of mental understanding. The paper turns to theories of joint action rather than theories of perception as some enactivists have done (cfr. Gallagher in Conscious Cognit 17(2):535–543, 2008; Thompson in J Conscious Stud 8(5–7):1–32, 2001), to gain insight into the kind of interactions that underpin our understanding of other minds, and in that way, supplement the interactionist-enactive account. In line with Enactivism, the paper argues that this kind of social understanding is practical rather than theoretical and that it is cognitively more basic and developmentally prior when compared to other ways we come to understand other minds.

     

Hume and the enactive approach to mind

An important part of David Hume’s work is his attempt to put the natural sciences on a firmer foundation by introducing the scientific method into the study of human nature. This investigation resulted in a novel understanding of the mind, which in turn informed Hume’s critical evaluation of the scope and limits of the scientific method as such. However, while these latter reflections continue to influence today’s philosophy of science, his theory of mind is nowadays mainly of interest in terms of philosophical scholarship. This paper aims to show that, even though Hume’s recognition in the cognitive sciences has so far been limited, there is an opportunity to reevaluate his work in the context of more recent scientific developments. In particular, it is argued that we can gain a better understanding of his overall philosophy by tracing the ongoing establishment of the enactive approach. In return, this novel interpretation of Hume’s ‘science of man’ is used as the basis for a consideration of the current and future status of the cognitive sciences.

Sensorimotor subjectivity and the enactive approach to experience

The enactive approach offers a distinctive view of how mental life relates to bodily activity at three levels: bodily self-regulation, sensorimotor coupling, and intersubjective interaction. This paper concentrates on the second level of sensorimotor coupling. An account is given of how the subjectively lived body and the living body of the organism are related (the body-body problem) via dynamic sensorimotor activity, and it is shown how this account helps to bridge the explanatory gap between consciousness and the brain. Arguments by O'Regan, Noë, and Myin that seek to account for the phenomenal character of perceptual consciousness in terms of ‘bodiliness’ and ‘grabbiness’ are considered. It is suggested that their account does not pay sufficient attention to two other key aspects of perceptual phenomenality: the autonomous nature of the experiencing self or agent, and the pre-reflective nature of bodily self-consciousness.     

Beyond localisation: a dynamical dual route account of face recognition

After decades of research the notion that faces are special is still at the heart of heated debates. New techniques like brain imaging have advanced some of the arguments but empirical data from brain-damaged patients like paradoxical recognition effects have required more complex explanations aside from localisation of the face area in normal adults. In this paper we focus on configural face processes and discuss configural processes in prosopagnosics in the light of findings obtained in brain-imaging studies. In order to account for data like paradoxical face recognition effects we propose a dual route model of face recognition. The model is based on the distinction between two separate aspects of face recognition, detection and identification, considered as dynamical and interrelated. In this perspective the face detection system appears as the stronger candidate for face-specific processes. The face identification system on the other hand is part of the object recognition system but derives its specificity in part from interaction with the face-specific detection system. The fact that face detection appears intact in some patients provides us with a possible explanation for the interference of configural processes on feature-based identification.     

Face value: testing the utility of contextual face cues for face recognition

The presence of multiple faces during a crime may provide a naturally-occurring contextual cue to support eyewitness recognition for those faces later. Across two experiments, we sought to investigate mechanisms underlying previously-reported cued recognition effects, and to determine whether such effects extended to encoding conditions involving more than two faces. Participants studied sets of individual faces, pairs of faces, or groups of four faces. At test, participants in the single-face condition were tested only on those individual faces without cues. Participants in the two and four-face conditions were tested using no cues, correct cues (a face previously studied with the target test face), or incorrect cues (a never-before-seen face). In Experiment 2, associative encoding was promoted by a rating task. Neither hit rates nor false-alarm rates were significantly affected by cue type or face encoding condition in Experiment 1, but cuing of any kind (correct or incorrect) in Experiment 2 appeared to provide a protective buffer to reduce false-alarm rates through a less liberal response bias. Results provide some evidence that cued recognition techniques could be useful to reduce false recognition, but only when associative encoding is strong.     

A sensorimotor account of vision and visual consciousness

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual "filling in," visual stability despite eye movements, change blindness, sensory substitution, and color perception.     

Searching for politicians: An information-processing approach to face recognition

Previous work on face recognition has concentrated on the processing of unfamiliar faces. This paper examines the recognition of already familiar faces, specifically politicians. Three experiments are described in which the subject's task was to search through a series of faces for particular target politicians. In Experiment I the function relating search time to target set size was found to be negatively accelerated. A similar function was observed when names were used as search items. In Experiment II all subjects searched for four targets, and the relationship between distractors and target items was varied. Distractors rated visually similar to the targets took longer to reject than those rated dissimilar. Distractors who were other politicians took longer to reject than actors, and this effect of semantic category was independent of visual similarity. In Experiment III, where subjects searched for a single target, semantic category appeared only to have an effect when the distractors were also visually similar to the target. Models of the rejection process are discussed, and the similarities between the effects observed here, with faces, and those reported elsewhere for words are pointed out.     

Tolerance for distorted faces: Challenges to a configural processing account of familiar face recognition

Face recognition is widely held to rely on ‘configural processing’, an analysis of spatial relations between facial features. We present three experiments in which viewers were shown distorted faces, and asked to resize these to their correct shape. Based on configural theories appealing to metric distances between features, we reason that this should be an easier task for familiar than unfamiliar faces (whose subtle arrangements of features are unknown). In fact, participants were inaccurate at this task, making between 8% and 13% errors across experiments. Importantly, we observed no advantage for familiar faces: in one experiment participants were more accurate with unfamiliars, and in two experiments there was no difference. These findings were not due to general task difficulty – participants were able to resize blocks of colour to target shapes (squares) more accurately. We also found an advantage of familiarity for resizing other stimuli (brand logos). If configural processing does underlie face recognition, these results place constraints on the definition of ‘configural’. Alternatively, familiar face recognition might rely on more complex criteria – based on tolerance to within-person variation rather than highly specific measurement.     

A statistical approach to sensorimotor strategies: conjugate cross-correlations

A simple method, based on cross-correlation functions (CCFs) between two time series of kinematic or physiological measurements, is proposed for the analysis of multisegmental movements. Special emphasis is placed on measuring accelerations. When the movements of two body segments are coordinated but consistently time lagged, their CCF displays a peak at the corresponding time abscissa. The reproducible positions of the peaks reflect biomechanical or physiological constraints. Several significantly large peaks can be observed in a CCF. It is possible to identify coordinated movements involving more than two segments by applying simple rules of compatibility between the time lags and between the signs of the correlation peaks. With the method proposed, it is possible to determine the signs of relative variation and the time lags of the successive statistically correlated segmental movements. This is particularly useful in the case of both continuous and periodic sensorimotor control, where classical poststimulus methods cannot be applied. Unlike the classical poststimulus methods, this method does not require a time origin, and it is not necessary to monitor the muscles or even to specify exactly which ones are involved. The method is also applicable to experiments involving a time origin (e.g., and applied perturbation), although in this case it is less accurate than the averaging technique. Individual postural strategies can be identified, which suggests some interesting potential applications of the method to clinical studies.     

A holistic account of the own-race effect in face recognition: evidence from a cross-cultural study

A robust finding in the cross-cultural research is that people's memories for faces of their own race are superior to their memories for other-race faces. However, the mechanisms underlying the own-race effect have not been well defined. In this study, a holistic explanation was examined in which Caucasian and Asian participants were asked to recognize features of Caucasian and Asian faces presented in isolation and in the whole face. The main finding was that Caucasian participants recognized own-race faces more holistically than Asian faces whereas Asian participants demonstrated holistic recognition for both own-race and other-race faces. The differences in holistic recognition between Caucasian and Asian participants mirrored differences in their relative experience with own-race and other-race faces. These results suggest that the own-race effect may arise from the holistic recognition of faces from a highly familiar racial group.     

A unified account of the effects of distinctiveness, inversion, and race in face recognition

A framework is outlined in which individual faces are assumed to be encoded as a point in a multidimensional space, defined by dimensions that serve to discriminate faces. It is proposed that such a framework can account for the effects of distinctiveness, inversion, and race on recognition of faces. Two specific models within this framework are identified: a norm-based coding model, in which faces are encoded as vectors from a population norm or prototype; and a purely exemplar-based model. Both models make similar predictions, albeit in different ways, concerning the interactions between the effects of distinctiveness, inversion and race. These predictions were supported in five experiments in which photographs of faces served as stimuli. The norm-based coding version and the exemplar-based version of the framework cannot be distinguished on the basis of the experiments reported, but it is argued that a multidimensional space provides a useful heuristic framework to investigate recognition of faces. Finally, the relationship between the specific models is considered and an implementation in terms of parallel distributed processing is briefly discussed.     

In search of the enactive: Introduction to special issue on enactive experience

Abstact In the decade and a half since the appearance of Varela, Thompson and Rosch's workThe Embodied Mind,enactivism has helped to put experience and consciousness, conceived of in a distinctive way, at the forefront of cognitive science. There are at least two major strands within the enactive perspective: a broad view of what it is to be an agent with a mind; and a more focused account of the nature of perception and perceptual experience. The relation between these two strands is discussed, with an overview of the papers presented in this volume.     

A test of the sensorimotor account of vision and visual perception

Two theories define the relationship between sensory experience and perception of location. The doctrine of specific nerve energies relies on hard-wired, genetically specified relationships between stimulation and perception, modifiable only within limits by adaptation. In a newer sensorimotor account, experience tunes the relationship between stimulation and perception. The perception of pressure phosphenes can differentiate the two theories, because the phosphene appears at a location predicted by physiological optics and in a modality predicted by specific nerve energies. Moving a finger vertically along the outer orbit of the eye while pressing gently on it through the lid during nasally directed gaze results in apparent motion of the phosphene out of phase with the finger, therefore in contradiction to information from motor efference to the finger, tactile sense at the fingertip, eyelid and bulb, joint receptors, and proprioception from muscles driving the finger. A test of the sensorimotor theory giving it every advantage had six observers in darkness moving their fingers along the eye and observing phosphenes for 1 h and 2400 motion cycles; the phosphene always obeyed the doctrine of specific nerve energies, never adapting or changing modality as the sensorimotor theory predicts.     

Face to face with emotion: holistic face processing is modulated by emotional state

Negative emotions are linked with a local, rather than global, visual processing style, which may preferentially facilitate feature-based, relative to holistic, processing mechanisms. Because faces are typically processed holistically, and because social contexts are prime elicitors of emotions, we examined whether negative emotions decrease holistic processing of faces. We induced positive, negative, or neutral emotions via film clips and measured holistic processing before and after the induction: participants made judgements about cued parts of chimeric faces, and holistic processing was indexed by the interference caused by task-irrelevant face parts. Emotional state significantly modulated face-processing style, with the negative emotion induction leading to decreased holistic processing. Furthermore, self-reported change in emotional state correlated with changes in holistic processing. These results contrast with general assumptions that holistic processing of faces is automatic and immune to outside influences, and they illustrate emotion's power to modulate socially relevant aspects of visual perception.     

Face age and sex modulate the other-race effect in face recognition

Faces convey a variety of socially relevant cues that have been shown to affect recognition, such as age, sex, and race, but few studies have examined the interactive effect of these cues. White participants of two distinct age groups were presented with faces that differed in race, age, and sex in a face recognition paradigm. Replicating the other-race effect, young participants recognized young own-race faces better than young other-race faces. However, recognition performance did not differ across old faces of different races (Experiments 1, 2A). In addition, participants showed an other-age effect, recognizing White young faces better than White old faces. Sex affected recognition performance only when age was not varied (Experiment 2B). Overall, older participants showed a similar recognition pattern (Experiment 3) as young participants, displaying an other-race effect for young, but not old, faces. However, they recognized young and old White faces on a similar level. These findings indicate that face cues interact to affect recognition performance such that age and sex information reliably modulate the effect of race cues. These results extend accounts of face recognition that explain recognition biases (such as the other-race effect) as a function of dichotomous ingroup/outgroup categorization, in that outgroup characteristics are not simply additive but interactively determine recognition performance.