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Human facial recognition in the context of surveillance, forensics and photo-ID verification is a task for which accuracy is critical. Quite often limitations in the overall quality of facial images reduces individuals' ability in taking decisions regarding a person's identity. To verify the suitability of advanced imaging techniques to improve individuals' performance in face matching we investigate how High Dynamic Range (HDR) imaging compares with traditional low (or standard) dynamic range (LDR) imaging in a facial recognition task. An HDR face dataset with five different lighting conditions is created. Subsequently, this dataset is used in a controlled experiment (N=40) to measure performance and accuracy of human participants when identifying faces in HDR vs LDR. Results demonstrate that face matching accuracy and reaction time are improved significantly by HDR imaging. This work demonstrates scope for realistic image reproduction and delivery in face matching tasks and suggests that security systems could benefit from the adoption of HDR imaging techniques.

Goal reflection can have a beneficial impact on hope and cognitive flexibility, potentially via processes proposed under the Broaden and Build Hypothesis (BBH). In the present study, a novel goal-oriented intervention was developed to explore its efficacy in improving state and trait hope, affect, and cognitive flexibility. Using a convergent mixed methods approach, 44 participants completed a seven-day diary intervention, recording/reflecting on goals daily, in addition to questionnaire and cognitive fluency measures pre- and post- intervention. The intervention elicited increased levels of state hope, trait agency, and task fluency with converging evidence from quantitative/qualitative data. These results suggest a dynamic interrelation between hope and cognitive flexibility.

Adults can ignore old and prioritize newly arriving visual stimuli, enabling optimal goal-directed search (visual marking; Watson & Humphreys, 1997). However, the ability to use time of appearance to enhance visual search is currently absent in work on attentional development in children. Experiment 1 examined children’s (6-, 8-, and 12-year-olds) and adults’ ability to ignore old and prioritize new stimuli and the relationship of this ability to executive functions. Experiment 2 examined whether the components involved in ignoring old items (encoding and maintenance) change across age, by presenting old stimuli for relatively short (500 ms), medium (1,000 ms) or long (1,500 ms) durations. On average, all age groups could ignore old items presented for 1,000 ms to some degree, however 25% of 6-year-olds were not able to prioritize new items effectively. No relationship was observed between the development of this ability and measures of executive function. On average, all age groups could ignore old items presented for short durations, however, 6-year-olds had difficulty ignoring stimuli presented for long durations. The findings suggest that the ability to ignore old items in order to prioritize search through new information is relatively weak in 6-year-olds, especially when ignoring items over longer durations. Furthermore, the findings indicate that the encoding and maintenance components involved in prioritizing new items might follow distinct developmental trajectories. (PsycINFO Database Record (c) 2018 APA, all rights reserved)\ud \ud

Facial stimuli have been shown to accrue a special status within visual processing, particularly when attention is prioritized to one face over another on the basis of affective content. This has been examined in relation to the ability of faces to guide or hold attention, or to resist attentional suppression. Previous work has shown that schematic faces can only be partially ignored and that the emotional valence of to-be-ignored faces has little effect. Given recent debates concerning the use of schematic faces, here we examined the ease with which photorealistic faces could be ignored. Although we found evidence of a partial preview benefit for these stimuli, the findings were complex, with stimulus salience, valence, and threat content interacting to affect both the strength of the benefit and target detection efficiency (Exps. 1-3). Experiment 4 then clarified the effects of physical salience and perceived stimulus similarity in the previous experiments, demonstrating that a combination of these factors is likely to account for the search patterns observed.

Six experiments examined the influence of emotional valence on the tagging and enumeration of multiple targets. Experiments 1, 5 and 6 found that there was no difference in the efficiency of tagging/enumerating multiple negative or positive stimuli. Experiment 2 showed that, when neutral-expression face distractors were present, enumerating negative targets was faster overall, but was only more efficient for small numbers of targets. Experiments 3 and 4 determined that this negative target advantage was most likely caused by increased attentional guidance to negatively-valenced stimuli and was not based on simple visual feature differences. The findings suggest that a multiple-target negative stimulus advantage will only occur under conditions of attentional competition, and for relatively small numbers of targets. The results are discussed in relation to theories of multiple- and single-item processing, threat-priority mechanisms, and the types of representations that support different attentional tasks.

Previous work has proposed that simple geometric shapes, carrying the features present within negative or threatening faces are especially effective at capturing or guiding attention. Here we test this account and provide converging evidence for a threat-based attentional advantage. Experiment 1 found that downward-pointing triangles continue to be detected more efficiently than upward-pointing triangles when: (i) both overall RT and search slope measures are obtained; and (ii) when the set size is varied and the stimuli are presented in random configurations. Experiment 2 tested and ruled out an alternative account of the selection advantage, based on differences between triangle shape consistencies with scene perspective cues. Overall, the data provide converging evidence that simple geometric shapes, which might be particularly important in providing emotional signals in faces, can also attract attention preferentially even when presented outside of a face context.

Negative compatibility effects (NCEs) in the masked-prime paradigm are usually obtained when primes are masked effectively. With ineffective masks-and primes above the perceptual threshold-positive compatibility effects (PCEs) occur. We investigated whether this pattern reflects a causal relationship between conscious awareness and low-level motor control, or whether it reflects the fact that both are affected in the same way by changes in physical stimulus attributes. In a 5-session perceptual learning task, participants learned to consciously identify masked primes. However, they showed unaltered NCEs that were not different from those produced by participants in a control group without equivalent perceptual learning. A control experiment demonstrated that no NCEs occur when prime identification is made possible by ineffective masking. The results suggest that perceptual awareness and low-level motor control are affected by the same factors, but are fundamentally independent of each other.

The visual marking mechanism (Watson & Humphreys, 1997) allows new objects to be prioritized by applying top-down inhibition to a set of previewed distractors, increasing the efficiency of future visual search. However, if this inhibition results in little or no search facilitation, do people continue to apply it or do they strategically withhold it? Here we present 6 experiments in which we examined how participants control this inhibitory mechanism. Experiments 1 to 3 showed that in difficult search contexts, participants did not modulate the extent to which they applied inhibition based on the proportion of trials in which inhibition would have been useful. This was the case, even when explicitly cued before each trial as to the utility of applying inhibition (Experiment 4). In contrast, when search was conducted in predominantly easy search contexts, there was some evidence that inhibition was applied strategically (Experiments 5 and 6); however, the extent of this control was relatively modest. The findings are discussed in terms of the mechanisms of top-down attentional control and implications for failures of attention in real-world contexts. (PsycINFO Database Record Language: en

It has been suggested that downward pointing triangles convey negative valence, perhaps because they mimic an underlying primitive feature present in negative facial expressions (Larson, Aronoff, and Stearns, 2007). Here, we test this proposition using a flanker interference paradigm in which participants indicated the valence of a central face target, presented between two adjacent distracters. Experiment 1 showed that, compared with face flankers, downward pointing triangles had little influence on responses to face targets. However, in Experiment 2, when attentional competition was increased between target and flankers, downward pointing triangles slowed responses to positively valenced face targets, and speeded them to negatively valenced targets, consistent with valence-based flanker compatibility effects. These findings provide converging evidence that simple geometric shapes may convey emotional valence.

Previewing a set of distractors allows them to be ignored in a subsequent visual search task (Watson & Humphreys, 1997). Seven experiments investigated whether this preview benefit can be obtained with emotional faces, and whether negative and positive facial expressions differ in the extent to which they can be ignored. Experiments 1-5 examined the preview benefit with neutral, negative, and positive previewed faces. These results showed that a partial preview benefit occurs with face stimuli, but that the valence of the previewed faces has little impact. Experiments 6 and 7 examined the time course of the preview benefit with valenced faces. These showed that negative faces were more difficult to ignore than positive faces, but only at short preview durations. Furthermore, a full preview benefit was not obtained with face stimuli even when the preview duration was extended up to 3 s. The findings are discussed in terms of the processes underlying the preview benefit, their ecological sensitivity, and the role of emotional valence in attentional capture and guidance.