Short term implicit memory in lexical processing

A single recent presentation of an item can lead to substantial improvementin speed or accuracy of processing when that item is presented subsequently, a phenomenon referred to as repetition priming. This empirical finding has been considered within two general frameworks. The first can be termed a "perceptual" approach, in which the perception of the target occurs more easily due to a transient change in the state of the target's internal representation. The second can be termed a "memory" approach, in which priming is seen as an example of implicit memory, that is, as arising from subconscious, nondeliberate access to a trace of an earlier event. This thesis examined repetition priming for words and nonwords from both perspectives. A review of priming within a word recognition framework suggested that transient modifications of lexical representations might be able to endure for several seconds, allowing a short-lived priming effect for words and word-like nonwords. A review of priming within a memory framework suggested that there might exist a short-lived implicit memory form, with a duration similar to that of explicit working memory. Empirical work examined priming over short lags (generally 0-23 items intervening between repeats) using lexical decision and speeded naming tasks. A novel short-lived repetition effect was apparent, superimposed on standard long-lived priming. For words, this effect endured until lag 3 (8 seconds). More rapid decay was apparent for nonwords, producing a lag x lexicality interaction. Short term priming was distinguished from long term priming on the basis of decay rate, the effects of word frequency, and the effects of the proportion of repeated items in the list. Short term priming was distinguished from explicit working memory on the basis of the effects of lexical status and overall differences in speed and accuracy. Finally, short term priming was shown to decay through the effects of both spontaneous trace loss and interference. The effect of interference on nonword priming was particularly severe, and the relative effects of interference were shown to be responsible for the form of the lag x lexicality interaction. The results are interpreted as showing that a) short term priming reflects the operation of a novel memory form, namely, short term implicit memory, (b) this memory arises {for lexical items) within the perceptual system responsible for word recognition, possibly through transient modification of orthographic representations, and (c) the word recognition system therefore retains a number of partially-active words simultaneously. It is suggested that short term implicit memory might exist to allow the integration of successively­ presented stimuli across a short time window of perceptual processing

New Tests to Measure Individual Differences in Matching and Labelling Facial Expressions of Emotion, and Their Association with Ability to Recognise Vocal Emotions and Facial Identity

Although good tests are available for diagnosing clinical impairments in face expression processing, there is a lack of strong tests for assessing "individual differences"--that is, differences in ability between individuals within the typical, nonclinical, range. Here, we develop two new tests, one for expression perception (an odd-man-out matching task in which participants select which one of three faces displays a different expression) and one additionally requiring explicit identification of the emotion (a labelling task in which participants select one of six verbal labels). We demonstrate validity (careful check of individual items, large inversion effects, independence from nonverbal IQ, convergent validity with a previous labelling task), reliability (Cronbach's alphas of.77 and.76 respectively), and wide individual differences across the typical population. We then demonstrate the usefulness of the tests by addressing theoretical questions regarding the structure of face processing, specifically the extent to which the following processes are common or distinct: (a) perceptual matching and explicit labelling of expression (modest correlation between matching and labelling supported partial independence); (b) judgement of expressions from faces and voices (results argued labelling tasks tap into a multi-modal system, while matching tasks tap distinct perceptual processes); and (c) expression and identity processing (results argued for a common first step of perceptual processing for expression and identity).This research was supported by the Australian Research Council (http://www.arc.gov.au/) grant DP110100850 to RP and EM and the Australian Research Council Centre of Excellence for Cognition and its Disorders (CE110001021) http://www.ccd.edu.au. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Reduced willingness to approach genuine smilers in social anxiety explained by potential for social evaluation, not misperception of smile authenticity

We investigate perception of, and responses to, facial expression authenticity for the first time in social anxiety, testing genuine and polite smiles. Experiment 1 (N = 141) found perception of smile authenticity was unaffected, but that approach ratings, which are known to be reduced in social anxiety for happy faces, are more strongly reduced for genuine than polite smiles. Moreover, we found an independent contribution of social anxiety to approach ratings, over and above general negative affect (state/trait anxiety, depression), only for genuine smiles, and not for polite ones. We argue this pattern of results can be explained by genuine smilers signalling greater potential for interaction – and thus greater potential for the scrutiny that is feared in social anxiety – than polite smiles. Experiment 2 established that, relative to polite smilers, genuine smilers are indeed perceived as friendlier and likely to want to talk for longer if approached. Critically, the degree to which individual face items were perceived as wanting to interact correlated strongly with the amount that social anxiety reduced willingness to approach in Experiment 1. We conclude it is the potential for social evaluation and scrutiny signalled by happy expressions, rather than their positive valence, that is important in social anxiety.This work was supported by the Australian Research Council (DP110100850; CE110001021, see ARC Centre of Excellence for Cognition and Its Disorders at www.ccd.edu.au)

Importance of the Inverted Control in Measuring Holistic Face Processing with the Composite Effect and Part-Whole Effect

Holistic coding for faces is shown in several illusions that demonstrate integration of the percept across the entire face. The illusions occur upright but, crucially, not inverted. Converting the illusions into experimental tasks that measure their strength - and thus index degree of holistic coding - is often considered straightforward yet in fact relies on a hidden assumption, namely that there is no contribution to the experimental measure from secondary cognitive factors. For the composite effect, a relevant secondary factor is size of the "spotlight" of visuospatial attention. The composite task assumes this spotlight can be easily restricted to the target half (e.g., top-half) of the compound face stimulus. Yet, if this assumption were not true then a large spotlight, in the absence of holistic perception, could produce a false composite effect, present even for inverted faces and contributing partially to the score for upright faces. We review evidence that various factors can influence spotlight size: race/culture (Asians often prefer a more global distribution of attention than Caucasians); sex (females can be more global); appearance of the join or gap between face halves; and location of the eyes, which typically attract attention. Results from five experiments then show inverted faces can sometimes produce large false composite effects, and imply that whether this happens or not depends on complex interactions between causal factors. We also report, for both identity and expression, that only top-half face targets (containing eyes) produce valid composite measures. A sixth experiment demonstrates an example of a false inverted part-whole effect, where encoding-specificity is the secondary cognitive factor. We conclude the inverted face control should be tested in all composite and part-whole studies, and an effect for upright faces should be interpreted as a pure measure of holistic processing only when the experimental design produces no effect inverted.Australian Research Council DP0984558 to Elinor McKone; Australian Research Council Centre of Excellence in Cognition and its Disorders (project number CE110001021); Kate Crookes salary supported by Hong Kong Research Grants Council grant (HKU744911) to William Hayward

All Tears Are Crocodile Tears: Impaired Perception of Emotion Authenticity in Psychopathic Traits

In everyday life, other peoples' distress is sometimes genuine (e.g., real sadness) and sometimes pretended (e.g., feigned sadness aimed at manipulating others). Here, we present the first study of how psychopathic traits affect responses to genuine versus posed distress. Using facial expression stimuli and testing individual differences across the general population (N = 140), we focus on the affective features of psychopathy (e.g., callousness, poor empathy, shallow affect). Results show that although individuals low on affective psychopathy report greater arousal and intent to help toward faces displaying genuine relative to posed distress, these differences weakened or disappeared with higher levels of affective psychopathy. Strikingly, a key theoretical prediction-that arousal should mediate the association between affective psychopathy and intent to help-was supported only for genuine distress and not for posed distress. A further novel finding was of reduced ability to discriminate the authenticity of distress expressions with higher affective psychopathy, which, in addition to and independently of arousal, also mediated the association between affective psychopathy and reduced prosociality. All effects were specific to distress emotions (did not extend to happiness, anger, or disgust), and to affective psychopathy (did not extend to Factor 2 psychopathy, disinhibition, or boldness). Overall, our findings are highly consistent with Blair's theorizing that atypical processing of distress emotions plays a key etiological role in the affective aspects of psychopathy. We go beyond these ideas to add novel evidence that unwillingness to help others is also associated with a failure to fully appreciate the authenticity of their distress.Australian Research Council Discovery Project grant to Elinor McKone (DP110100850); Australian Research Council Centre of Excellence for Cognition and Its Disorders (CE110001021

Caricaturing faces to improve identity recognition in low vision simulations: How effective is current-generation automatic assignment of landmark points?

Purpose: Previous behavioural studies demonstrate that face caricaturing can provide an effective image enhancement method for improving poor face identity perception in low vision simulations (e.g., age-related macular degeneration, bionic eye). To translate caricaturing usefully to patients, assignment of the multiple face landmark points needed to produce the caricatures needs to be fully automatised. Recent development in computer science allows automatic face landmark detection of 68 points in real time and in multiple viewpoints. However, previous demonstrations of the behavioural effectiveness of caricaturing have used higherprecision caricatures with 147 landmark points per face, assigned by hand. Here, we test the effectiveness of the auto-assigned 68-point caricatures. We also compare this to the hand-assigned 147-point caricatures. Method: We assessed human perception of how different in identity pairs of faces appear, when veridical (uncaricatured), caricatured with 68-points, and caricatured with 147-points. Across two experiments, we tested two types of low-vision images: a simulation of blur, as experienced in macular degeneration (testing two blur levels); and a simulation of the phosphenised images seen in prosthetic vision (at three resolutions). Results: The 68-point caricatures produced significant improvements in identity discrimination relative to veridical. They were approximately 50% as effective as the 147-point caricatures. Conclusion: Realistic translation to patients (e.g., via real time caricaturing with the enhanced signal sent to smart glasses or visual prosthetic) is approaching feasibility. For maximum effectiveness software needs to be able to assign landmark points tracing out all details of feature and face shape, to produce high-precision caricatures.This work was funded by the Australian Research Council (http://www.arc.gov.au/) grant DP150100684 to EM and National Health and Medical Research Council (https://www.nhmrc.gov.au/) 1082358 to NB

A new theoretical approach to improving face recognition in disorders of central vision: Face caricaturing

Damage to central vision, of which age-related macular degeneration (AMD) is the most common cause, leaves patients with only blurred peripheral vision. Previous approaches to improving face recognition in AMD have employed image manipulations designed to enhance early-stage visual processing (e.g., magnification, increased HSF contrast). Here, we argue that further improvement may be possible by targeting known properties of mid- and/or high-level face processing. We enhance identity-related shape information in the face by caricaturing each individual away from an average face. We simulate early- through late-stage AMD-blur by filtering spatial frequencies to mimic the amount of blurring perceived at approximately 10° through 30° into the periphery (assuming a face seen premagnified on a tablet computer).We report caricature advantages for all blur levels, for face viewpoints from front view to semiprofile, and in tasks involving perceiving differences in facial identity between pairs of people, remembering previously learned faces, and rejecting new faces as unknown. Results provide a proof of concept that caricaturing may assist in improving face recognition in AMD and other disorders of central vision

A robust method of measuring other-race and other-ethnicity effects: the Cambridge Face Memory Test format

Other-race and other-ethnicity effects on face memory have remained a topic of consistent research interest over several decades, across fields including face perception, social psychology, and forensic psychology (eyewitness testimony). Here we demonstrate that the Cambridge Face Memory Test format provides a robust method for measuring these effects. Testing the Cambridge Face Memory Test original version (CFMT-original; European-ancestry faces from Boston USA) and a new Cambridge Face Memory Test Chinese (CFMT-Chinese), with European and Asian observers, we report a race-of-face by race-of-observer interaction that was highly significant despite modest sample size and despite observers who had quite high exposure to the other race. We attribute this to high statistical power arising from the very high internal reliability of the tasks. This power also allows us to demonstrate a much smaller within-race other ethnicity effect, based on differences in European physiognomy between Boston faces/observers and Australian faces/observers (using the CFMT-Australian)

Why the other-race effect matters: Poor recognition of other-race faces impacts everyday social interactions

What happens to everyday social interactions when other-race recognition fails? Here, we provide the first formal investigation of this question. We gave East Asian international students (N = 89) a questionnaire concerning their experiences of the other-race effect (ORE) in Australia, and a laboratory test of their objective other-race face recognition deficit using the Cambridge Face Memory Test (CFMT). As a 'perpetrator' of the ORE, participants reported that their problems telling apart Caucasian people contributed significantly to difficulties socializing with them. Moreover, the severity of this problem correlated with their ORE on the CFMT. As a 'victim' of the ORE, participants reported that Caucasians' problems telling them apart also contributed to difficulties socializing. Further, 81% of participants had been confused with other Asians by a Caucasian authority figure (e.g., university tutor, workplace boss), resulting in varying levels of upset/difficulty. When compared to previously established contributors to international students' high rates of social isolation, ORE-related problems were perceived as equally important as the language barrier and only moderately less important than cultural differences. We conclude that the real-world impact of the ORE extends beyond previously identified specialized settings (eyewitness testimony, security), to common everyday situations experienced by all humans.Research was supported by the Australian Research Council DP15 DP150100684 to EM andDECRA number DE180100015 to YS

Importance of the inverted control in measuring holistic face processing with the composite effect and part-whole effect

Holistic coding for faces is shown in several illusions that demonstrate integration of the percept across the entire face. The illusions occur upright but, crucially, not inverted. Converting the illusions into experimental tasks that measure their strength - and thus index degree of holistic coding - is often considered straightforward yet in fact relies on a hidden assumption, namely that there is no contribution to the experimental measure from secondary cognitive factors. For the composite effect, a relevant secondary factor is size of the "spotlight" of visuospatial attention. The composite task assumes this spotlight can be easily restricted to the target half (e.g., top-half) of the compound face stimulus. Yet, if this assumption were not true then a large spotlight, in the absence of holistic perception, could produce a false composite effect, present even for inverted faces and contributing partially to the score for upright faces.We reviewevidence that various factors can influence spotlight size: race/culture (Asians often prefer a more global distribution of attention than Caucasians); sex (females can be more global); appearance of the join or gap between face halves; and location of the eyes, which typically attract attention. Results from five experiments then show inverted faces can sometimes produce large false composite effects, and imply that whether this happens or not depends on complex interactions between causal factors. We also report, for both identity and expression, that only top-half face targets (containing eyes) produce valid composite measures. A sixth experiment demonstrates an example of a false inverted part-whole effect, where encoding-specificity is the secondary cognitive factor.We conclude the inverted face control should be tested in all composite and part-whole studies, and an effect for upright faces should be interpreted as a pure measure of holistic processing only when the experimental design produces no effect inverted