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Elinor McKone

Publications and source records attributed to Elinor McKone.

11 recordsLinked to original sources

Can generic expertise explain special processing for faces?

Does face recognition involve face-specific cognitive and neural processes ('domain specificity') or do faces only seem special because people have had more experience of individuating them than they have of individuating members of other homogeneous object categories ('the expertise hypothesis')? Here, we summarize new data that test these hypotheses by assessing whether classic face-selective effects - holistic processing, recognition impairments in prosopagnosia and fusiform face area activation - remain face selective in comparison with objects of expertise. We argue that evidence strongly supports domain specificity rather than the expertise hypothesis. We conclude that the crucial social function of face recognition does not reflect merely a general practice phenomenon and that it might be supported by evolved mechanisms (visual or nonvisual) and/or a sensitive period in infancy.

Animals↗

The evidence rejects the expertise hypothesis: reply to Gauthier & Bukach.

In Robbins, R. & McKone, E. (2006). No face-like processing for object-of-expertise in three behavioural tasks. Cognition this issue, we showed face-like holistic/configural processing does not occur for objects-of-expertise on standard paradigms including inversion, part-whole, part-in-configurally-transformed-whole, and the standard composite task. In this reply to the discussion by Gauthier, I., & Bukach, C. (2006). Should we reject the expertise hypothesis? Cognition, this issue, we focus on several issues: the fact that they do not dispute our review of previous data; the strength of null effects obtained from multiple studies and paradigms; the evidence for domain-specificity of the neural substrate supporting face processing; the difference between the expertise hypothesis (as a theory about the origin of face processing) and studies of how experience affects object processing in general; and the problems with G&B's proposed alteration to the standard composite paradigm. We argue that overwhelming evidence suggests the expertise hypothesis should be put to rest so that researchers can focus on what the origin of "special" processing for faces actually is, and investigate the many interesting changes to object recognition that do occur with experience.

Face↗

No face-like processing for objects-of-expertise in three behavioural tasks.

In the debate between expertise and domain-specific explanations of "special" processing for faces, a common belief is that behavioural studies support the expertise hypothesis. The present article refutes this view, via a combination of new data and review. We tested dog experts with confirmed good individuation of exemplars of their breed-of-expertise. In all experiments, standard results were confirmed for faces. However, dog experts showed no face-like processing for dogs on three behavioural tasks (inversion; the composite paradigm; and sensitivity to contrast reversal). The lack of holistic/configural processing, indicated in the first two of these tests, is shown by review to be consistent rather than inconsistent with previous studies of objects-of-expertise.

Adult↗

Sensitivity of 4-year-olds to featural and second-order relational changes in face distinctiveness.

Sensitivity to adult ratings of facial distinctiveness (how much an individual stands out in a crowd) has been demonstrated previously in children age 5 years or older. Experiment 1 extended this result to 4-year-olds using a "choose the more distinctive face" task. Children's patterns of choice across item pairs also correlated well with those of adults. In Experiment 2, original faces were made more distinctive via local feature changes (e.g., bushier eyebrows) or via relational changes (spacing changes, e.g., eyes closer together). Some previous findings suggest that children's sensitivity develops more slowly to relational changes than to featural changes. However, when we matched featural and relational changes for effects on distinctiveness in adult participants, 4-year-olds were equally sensitive to both. Our results suggest that (a) 4-year-olds' face space has important aspects of structure in common with that of adults and that (b) there is no specific developmental delay for a second-order relational component of configural/holistic processing.

Adult↗

Memory conjunction errors for realistic faces are consistent with configural processing.

Conjunction faces are formed from feature sets learned across different faces. In previous studies, false alarms ("old" responses) to conjunctions have been very high, approaching hits to old faces; this is surprising, because, perceptually, upright faces are processed configurally, with strong integration of parts into the whole. We test the idea that the atypical reliance on unrelated parts could be due to using unnatural line drawings as stimuli, and to forming conjunctions across external features (e.g., hair) and internal features (e.g., eyes, mouth). We used realistic face stimuli and conjunctions made entirely from internal features. Results were, as expected, consistent with configural processing for upright faces (hits to old faces much greater than FA to conjunctions) and not for inverted faces (hits to old = FA to conjunctions).

Association Learning↗

Orientation tuning of human face processing estimated by contrast matching in transparency displays.

Upright images of faces appear more salient than faces of other orientations. We exploited this effect in a titration experiment where faces were superimposed in transparency. By manipulating the physical contrast of the component images, we measured the degree of perceptual dominance as function of the orientation of the face in the image plane. From these measurements, we obtain the orientation tuning of face processing, which is well approximated by a Gaussian function with a SD of about 45 deg and mean centered on upright. Faces predominantly lit from above and from below produced very similar results. However, when presented with scrambled faces observers showed no orientation preference. We argue that these results can be explained by the existence of specialized face processing mechanisms with an orientation tuning with a bandwidth of approximately 90 deg, predominantly centered on the upright orientation and easily disrupted by alterations of the normal facial configuration.

Contrast Sensitivity↗

Categorical and coordinate relations in faces, or Fechner's law and face space instead?

E. E. Cooper and T. J. Wojan (2000) applied the categorical-coordinate relations distinction to faces on the basis of a finding that two-eyes-up versus one-eye-up distortions had opposite effects in between-class (face normality) and within-class (face identity) tasks. However, Cooper and Wojan failed to match amount of metric change between their 2 deviation types and tested only 1 deviation level. In the present study, eyeheight was shifted (e.g., both eyes up or both eyes down vs. one eye up and one eye down) parametrically (11 levels) and normality and identity ratings obtained. There was no evidence of categorical changes in perception where these would have been predicted by Cooper and Wojan's theory. In all cases, the relationship between physical and perceived distortion followed Fechner's law. Differences across distortion types in Fechner threshold (the minimum deviation altering perceived normality or identity) are explained in terms of the variability associated with different dimensions in face space.

Face↗

Adults with dyslexia show deficits on spatial frequency doubling and visual attention tasks.

We examine the visual processing of high-functioning adults with developmental dyslexia (mean Performance IQ = 126.5) and current phonological problems. In comparison to an age- and IQ-matched control group, the group with dyslexia showed deficits in two tasks associated with magnocellular/dorsal pathway function. For the 'frequency doubling' stimulus (grating of 0.25 cpd modulated at 25 Hz counterphase flicker), contrast thresholds for detection were raised in the dyslexic group. In conjunction visual search, a display time sufficient for controls to achieve ceiling accuracy at all set sizes (30 ms per item) was inadequate to allow shifts of attention around the display for the group with dyslexia. In contrast, normal performance was found on 'popout' visual search and on a ventral stream acuity task. Correlational analysis revealed a significant relationship between degree of deficit in conjunction search and phonological difficulty. The deficits revealed were specific to functions that rely on magnocellular input. They cannot be attributed to concentration lapses, eye movement problems or slow reaction times in the dyslexic group.

Adult↗

Isolating the special component of face recognition: peripheral identification and a Mooney face.

A previous finding argues that, for faces, configural (holistic) processing can operate even in the complete absence of part-based contributions to recognition. Here, this result is confirmed using 2 methods. In both, recognition of inverted faces (parts only) was removed altogether (chance identification of faces in the periphery; no perception of a particularly hard-to-see Mooney face). Recognition of upright faces (configural plus parts), however, remained good. The simplicity of these new "isolation" techniques makes them ideal for (a) assessing configural processing in specialist populations (e.g., children, object experts) and (b) exploring properties of configural processing for faces in detail. As an example of the latter, orientation tuning was tested. Results argue against models in which faces are rotated to upright prior to identification.

Cues↗

Can holistic processing be learned for inverted faces?

The origin of "special" processing for upright faces has been a matter of ongoing debate. If it is due to generic expertise, as opposed to having some innate component, holistic processing should be learnable for stimuli other than upright faces. Here we assess inverted faces. We trained subjects to discriminate identical twins using up to 1100 exposures to each twin in different poses and images. In the upright orientation, twin discrimination was supported by holistic processing. Removal of a single face feature had no effect on performance, and a composite effect (Young, A. W., Hellawell, D., & Hay, D.C. (1987). Configurational information in face perception. Perception 16 (6), 747-759) was obtained. In the inverted orientation, however, above chance identification ability relied on (a) image specific learning, or (b) tiny local feature differences not noticed in the upright faces. The failure to learn holistic processing for inverted faces indicates that, in contrast to the situation for objects (Tarr, M.J., & Pinker, S. (1989). Mental rotation and orientation-dependence in shape recognition. Cognitive Psychology 21 (2), 233-282), orientation specificity of face processing is highly stable against practice.

Adolescent↗

Dissociations between implicit and explicit memory in children: the role of strategic processing and the knowledge base.

A review of the literature shows that explicit memory develops substantially from three years of age to adulthood, while implicit memory remains stable across this age range. Previously, this developmental dissociation has been attributed to different memory systems, or to confounds with perceptual vs. conceptual processing. Prompted by an alternative developmental framework, the experiments reported here provide evidence against both interpretations. Instead, it will be argued that (a) the implicit-explicit developmental dissociation reflects differences in strategic processing (strategy use and metamemory) across childhood and (b) that implicit memory can show development if a child's knowledge base in the tested domain is developing with age.

Adolescent↗