Chao-Chih Wang’s research while affiliated with National Tsing Hua University and other places

Cognitive load significantly influences learning effectiveness. All the three types of cognitive load—intrinsic, extraneous, and germane—are important for guiding teachers in preparing effective instructional designs for students. However, the techniques used to assess the relationship between brain activity and cognitive load during learning activities require further investigation. This study preliminarily examined cognitive load during mathematics computations based on cognitive-load theory. We used event-related potentials to compare carryover and without carryover additions under three types of stimuli (uncoloured Arabic numerals, colourful Arabic numerals, and Chinese numerals) to measure learners’ cognitive load. According to the concept and rationale of cognitive-load theory, the design defined the extraneous and germane cognitive load to measure the N1 and P2 components and the relevant behavioural data. The highest P2 amplitude was observed in the Chinese numerals condition as extraneous cognitive load, and the N1 component was observed in the colourful Arabic numerals condition as germane cognitive load. Thus, both components may play an important role in extraneous and germane cognitive load. Additionally, these exhibit negative correlations during mathematical computations. This study’s findings and implications offer insights into future ways for assessing cognitive load using brain imaging techniques and potential applications for brain–computer interfaces.

Background: Holistic processing is defined as the perceptual integration of facial features, and plays an important role in face recognition. While researchers recognize the crucial role played by holistic processing in face perception, a complete delineation of the underlying mechanisms is impending. Very few studies have examined the effects of perceptual discrimination and spatial perception on holistic processing. Hence, the present study aimed to examine the influence of perceptual discrimination and spatial perception on face recognition. Methods: We conducted two experiments by manipulating the perceptual discriminability of the target (the top-half faces) and non-target face (the bottom-half faces) parts in the composite-face task and examined how perceptual discriminability may affect holistic processing of faces. Results: The results of Experiment 1 illustrated that holistic processing was modulated by the perceptual discriminability of the face. Furthermore, differential patterns of perceptual discriminability with the target and non-target parts suggested that different mechanisms may be responsible for the influence of target and non-target parts on face perception. The results of Experiment 2 illustrated that holistic processing was modulated by spatial distance between two faces, implicating that feature-by-feature strategy might decrease the magnitude of holistic processing. Conclusion: The results of the present study suggest that holistic processing may lead to augmented perception effect exaggerating the differences between the two faces and may also be affected by the feature-by-feature strategy.

Human has an exceptional ability for face recognition to keep up social network. However, it is unclear to understand the mechanisms of face recognition until now. Specifically, there is less research to examine the time course of part-based and holistic processing when these two routes trigger and finish. In the present experiments, the exposure time was manipulated to examine the time course of face processing and found evidence suggesting that holistic processing occurs shortly after part-based processing at about 200 ms, and can last for a relatively long duration up to 2,000 ms. These results may support to a dual-route model comprising holistic processing and part-based processing in face perception. Moreover, our findings were inconsistent with the previous study which suggests that no holistic processing was observed at the relatively long duration, and suspected that perceptual discriminability may have been responsible for the discrepancy.

The Vanderbilt Holistic Face Processing Test (VHPT-F) is a new measure of holistic face processing with better psychometric properties relative to prior measures developed for group studies (Richler et al., 2014). In fields where psychologists study individual differences, validation studies are commonplace and the concurrent validity of a new measure is established by comparing it to an older measure with established validity. We follow this approach and test whether the VHPT-F measures the same construct as the composite task, which is group-based measure at the center of the large literature on holistic face processing. In Experiment 1, we found a significant correlation between holistic processing measured in the VHPT-F and the composite task. Although this correlation was small, it was comparable to the correlation between holistic processing measured in the composite task with the same faces, but different target parts (top or bottom), which represents a reasonable upper limit for correlations between the composite task and another measure of holistic processing. These results confirm the validity of the VHPT-F by demonstrating shared variance with another measure of holistic processing based on the same operational definition. These results were replicated in Experiment 2, but only when the demographic profile of our sample matched that of Experiment 1.

The composite face task is one of the most popular research paradigms for measuring holistic processing of upright faces. The exact mechanism underlying holistic processing remains elusive and controversial, and some studies have suggested that holistic processing may not be evenly distributed, in that the top-half of a face might induce stronger holistic processing than its bottom-half counterpart. In two experiments, we further examined the possibility of asymmetric holistic processing. Prior to Experiment 1, we confirmed that perceptual discriminability was equated between top and bottom face halves; we found no differences in performance between top and bottom face halves when they were presented individually. Then, in Experiment 1, using the composite face task with the complete design to reduce response bias, we failed to obtain evidence that would support the notion of asymmetric holistic processing between top and bottom face halves. To further reduce performance variability and to remove lingering holistic effects observed in the misaligned condition in Experiment 1, we doubled the number of trials and increased misalignment between top and bottom face halves to make misalignment more salient in Experiment 2. Even with these additional manipulations, we were unable to find evidence indicative of asymmetric holistic processing. Taken together, these findings suggest that holistic processing is distributed homogenously within an upright face.

Face composite task has been one of the most prevalent research paradigms to demonstrate holistic processing of upright faces. Many researchers examined the exact mechanism underlying holistic processing, but holistic processing and its representation still remain elusive and controversial, some studies have suggested that holistic processing may not be evenly distributed in that processing the top-half of a face might induce stronger holistic processing than processing its bottom-half counterpart. However, the previous studies may have suffered from inadequate control of perceptual similarity between the top and bottom parts of face stimuli. In the present study, we manipulated independently perceptual similarity between the relevant (top) and irrelevant (bottom) parts of face stimuli, such that the relevant part of high versus low similarity were joined by the irrelevant part of high versus low similarity to form composite faces. Participants were asked to judge whether relevant parts of two composite faces were the same or different in a complete design. The results revealed that when the irrelevant parts were of low similarity, holistic processing as indexed by congruency effect was stronger than when irrelevant parts were highly similar. In contrast, whether or not the relevant parts were of high or low similarity, comparable levels of holistic processing were obtained. Taken together, these findings suggest that perceptual similarity, especially of the irrelevant parts, can modulate holistic processing of composite faces. Moreover, previous findings claiming asymmetry of holistic processing between top and bottom parts may be attributed to differences in perceptual similarity of the specific face stimuli that were used. Meeting abstract presented at VSS 2016

Face composite task has been one of the most popular research paradigms for securing evidence for holistic processing of upright faces. Aside from the fact that the exact mechanism underlying holistic processing remains elusive and controversial, some studies have suggested that holistic processing may not be evenly distributed in that processing the top-half of a face might induce stronger holistic processing than processing its bottom-half counterpart. Here in three experiments we further examined the possibility of asymmetric holistic processing. In Experiment 1, we equated perceptual discriminability between the top-half and the bottom-half of a face by showing only face halves and found no differences in performance between the two halves. In Experiment 2, using the face composite task with a complete design to reduce response bias, we failed to obtain evidence that would support the notion of asymmetric holistic processing between the top-half and bottom-half faces. Finally, in Experiment 3, in order to further reduce performance variability and to remove lingering holistic effect observed in the misalignment condition of Experiment 2, we doubled the number of trials and enlarged misalignment between top half and bottom half of a face to make it more visible. Even with these additional manipulations, we were unable to find evidence indicative of asymmetric holistic processing. Taken together, these findings suggest that holistic processing may well distribute homogenously within an upright face and support the perceptual field hypothesis where an upright face would induce relatively large perceptual field encompassing the entire face. Meeting abstract presented at VSS 2015.