Typing is essential for communication, yet the input behavior of individuals with cerebral palsy (CP) remains underexplored. We investigated 31 CP typists and 31 non-disabled controls using keystroke logging, eye tracking, and motion capture. Our study found that CP typists were slower and less rhythmically stable, but by prioritizing accuracy, their overall keyboard efficiency was comparable to controls. They adopted compensatory visual strategies such as shorter and more frequent fixations, greater reliance on the keyboard, and more gaze shifts, and displayed diverse finger usage strategies from single-finger to multi-finger input. We found that using more fingers did not necessarily result in faster typing. Subtype analysis showed spastic CP typists followed a "slow but steady" rhythm with consistent inter-key intervals, whereas athetoid CP typists exhibited a "fast but unstable" rhythm with greater variability, highlighting distinct mechanisms of typing in CP and providing insights for personalized assistive technologies.

Dysarthric speech recognition (DSR) is an emerging field that can enhance social interactions and mental health for individuals with dysarthria. However, the lack of sufficient Chinese dysarthric speech data and challenges like ambiguity and individual differences hinder performance improvements. Text-to-speech (TTS) technology is well-established in normal speech recognition and can also supplement dysarthric speech data. This study explores the impact of TTS-based Chinese dysarthric speech generation on DSR performance. Speaker-dependent experiments show that synthetic dysarthric speech alone does not effectively improve DSR performance. Through statistical analysis of acoustic features, we reveal the disparities between synthetic and authentic speech in dysarthria and highlight the limitations of synthetic data for DSR. These findings provide insights for future improvements in speech generation methods.

Facial micro-expressions (MEs) are involuntary movements of the face that occur spontaneously when a person experiences an emotion but attempts to suppress or repress the facial expression, typically found in a high-stakes environment. In recent years, substantial advancements have been made in the areas of ME recognition, spotting, and generation. However, conventional approaches that treat spotting and recognition as separate tasks are suboptimal, particularly for analyzing long-duration videos in realistic settings. Concurrently, the emergence of multimodal large language models (MLLMs) and large vision-language models (LVLMs) offers promising new avenues for enhancing ME analysis through their powerful multimodal reasoning capabilities. The ME grand challenge (MEGC) 2025 introduces two tasks that reflect these evolving research directions: (1) ME spot-then-recognize (ME-STR), which integrates ME spotting and subsequent recognition in a unified sequential pipeline; and (2) ME visual question answering (ME-VQA), which explores ME understanding through visual question answering, leveraging MLLMs or LVLMs to address diverse question types related to MEs. All participating algorithms are required to run on this test set and submit their results on a leaderboard. More details are available at https://megc2025.github.io.

Micro-expressions (MEs) are brief, subtle facial expressions that reveal concealed emotions, offering key behavioral cues for social interaction. Characterized by short duration, low intensity, and spontaneity, MEs have been mostly studied through subjective coding, lacking objective, quantitative indicators. This paper explores ME characteristics using facial electromyography (EMG), analyzing data from 147 macro-expressions (MaEs) and 233 MEs collected from 35 participants. First, regarding external characteristics, we demonstrate that MEs are short in duration and low in intensity. Precisely, we proposed an EMG-based indicator, the percentage of maximum voluntary contraction (MVC%), to measure ME intensity. Moreover, we provided precise interval estimations of ME intensity and duration, with MVC% ranging from 7% to 9.2% and the duration ranging from 307 ms to 327 ms. This research facilitates fine-grained ME quantification. Second, regarding the internal characteristics, we confirm that MEs are less controllable and consciously recognized compared to MaEs, as shown by participants' responses and self-reports. This study provides a theoretical basis for research on ME mechanisms and real-life applications. Third, building on our previous work, we present CASMEMG, the first public ME database including EMG signals, providing a robust foundation for studying micro-expression mechanisms and movement dynamics through physiological signals.

Micro-expressions (MEs) are brief, involuntary facial movements critical for detecting lies, drawing growing interest in psychology and computer science. However, annotating ME can burden human coders with excessive time commitment and overwhelming information that compromises coding reliability and efficiency. Such difficulties in data annotation also led to the small sample size problem and hindered the development of ME analysis. Specifically, our psychological research highlights the complexities involved in human annotation of key frames. To facilitate the annotating process of ME, we proposed the Micro-Expression Key Frame Inference (ME-KFI) problem, aiming to identify MEs’ temporal locations from a single frame, reducing manual annotation effort. We propose a Micro-Expression Contrastive Identification Annotation (MECIA) method as a solution to ME-KFI, including three modules: a contrastive module, an identification module, and an annotation module, corresponding to the three steps of manual annotation. The network’s outputs infer the key frame of ME clips. MECIA demonstrates superior performance over random baselines on SAMM and CAS(ME)$^{2}$databases and maintains comparable recognition accuracy with ground-truth clips.

Recent studies proposed above-the-neck gestures for people with upper-body motor impairments interacting with mobile devices without finger touch, resulting in an appropriate user-defined gesture set. However, many gestures involve sustaining eyelids in closed or open states for a period. This is challenging for people with dystonia, who have difficulty sustaining and intermitting muscle contractions. Meanwhile, other facial parts, such as the tongue and nose, can also be used to alleviate the sustained use of eyes in the interaction. Consequently, we conducted a user study inviting 16 individuals with dystonia to design gestures based on facial muscle movements for 26 common smartphone commands. We collected 416 user-defined head gestures involving facial features and shoulders. Finally, we obtained the preferred gestures set for individuals with dystonia. Participants preferred to make the gestures with their heads and use unnoticeable gestures. Our findings provide valuable references for the universal design of natural interaction technology.

Facial micro-expressions (MEs) are involuntary spontaneous movements of the face that typically appear in high-stakes situations where a person attempts to conceal a certain emotion from being known. A decade after the inception of the widely used CASME II and SMIC datasets, research in computational analysis of MEs has now advanced toward new pathways, exploring problems crucial to model generalization and real-world practicality. It is often challenging to design robust algorithms or models for spotting micro-expressions due to the high variability across diverse cultural backgrounds. Also, treating spotting and recognition as separate tasks is undesirable when handling long-spanning videos under realistic settings. This Grand Challenge comprises two distinct tracks: the Cross-Cultural Spotting (CCS) track, and the Spot-Then-Recognize (STR) track. All participating solutions submitted their results to a leaderboard, and several submissions performed well surpassing their respective baseline results. More details are available at: https://megc2024.github.io.

Facial micro-expressions (MEs) are involuntary movements of the face that occur spontaneously when a person experiences an emotion but attempts to suppress or repress the facial expression, typically found in a high-stakes environment. Unfortunately, the small sample problem severely limits the automation of ME analysis. Furthermore, due to the weak and transient nature of MEs, it is difficult for models to distinguish it from other types of facial actions. Therefore, ME in long videos is a challenging task, and the current performance cannot meet the practical application requirements. Addressing these issues, this challenge focuses on ME and the macro-expression (MaE) spotting task. This year, in order to evaluate algorithms' performance more fairly, based on CAS(ME)2, SAMM Long Videos, SMIC-E-long, CAS(ME)3 and 4DME, we build an unseen cross-cultural long-video test set. All participating algorithms are required to run on this test set and submit their results on a leaderboard with a baseline result.

Micro-expressions are facial movements that are extremely short and not easily detected, which often reflect the genuine emotions of individuals. Micro-expressions are important cues for understanding real human emotions and can be used for non-contact, non-perceptual deception detection, or abnormal emotion recognition. It has broad application prospects in national security, judicial practice, health prevention, and clinical practice. However, micro-expression feature extraction and learning are highly challenging because they are typically short in duration, low intensity, and have local facial asymmetry. In addition, the intelligent micro-expression analysis combined with deep learning technology is also plagued by the problem of relatively small data samples. Not only is micro-expression elicitation very difficult, micro-expression annotation is also very time-consuming and laborious. More importantly, the micro-expression generation mechanism is not yet clear, which shackles the application of micro-expressions in real scenarios. FME'23 is the inaugural workshop in this area of research, with the aim of promoting interactions between researchers and scholars from within this niche area of research. This year we hope to discuss the growing ethical conversations when using face data, and how we can come to a consensus on micro-expression standards within affective computing.

Micro-expression (ME) is a significant non-verbal communication clue that reveals one person's genuine emotional state. The development of micro-expression analysis (MEA) has just gained attention in the last decade. However, the small sample size problem constrains the use of deep learning on MEA. Besides, ME samples distribute in six different databases, leading to database bias. Moreover, the ME database development is complicated. In this article, we introduce a large-scale spontaneous ME database: CAS(ME)3. The contribution of this article is summarized as follows: (1) CAS(ME)3offers around 80 hours of videos with over 8,000,000 frames, including manually labeled 1,109 MEs and 3,490 macro-expressions. Such a large sample size allows effective MEA method validation while avoiding database bias. (2) Inspired by psychological experiments, CAS(ME)3provides the depth information as an additional modality unprecedentedly, contributing to multi-modal MEA. (3) For the first time, CAS(ME)3elicits ME with high ecological validity using the mock crime paradigm, along with physiological and voice signals, contributing to practical MEA. (4) Besides, CAS(ME)3provides 1,508 unlabeled videos with more than 4,000,000 frames, i.e., a data platform for unsupervised MEA methods. (5) Finally, we demonstrate the effectiveness of depth information by the proposed depth flow algorithm and RGB-D information.

Micro-expressions (MEs) are very important nonverbal communication clues. However, due to their local and short nature, spotting them is challenging. In this article, we address this problem by using a dedicated local and temporal pattern (LTP) of facial movement. This pattern has a specific shape (an S-pattern) when MEs are displayed. Thus, by using a classic classification algorithm (SVM), MEs can be distinguished from other facial movements. We also propose a global final fusion analysis covering the whole face to improve the distinction between ME (local) and head (global) movements. However, the learning of S-patterns is limited by the small number of ME databases and the low volume of ME samples. Hammerstein models (HMs) are known to effectively approximate muscle movements. By approximating each S-pattern with an HM, we can both filter out outliers and generate new similar S-patterns. In this way, we augment the dataset for S-pattern training and improve the ability to differentiate MEs from other movements. The spotting results, performed in the CASMEI and CASMEII databases, show that our proposed LTP outperforms the most popular spotting method in terms of the F1-score. Adding a fusion process and data augmentation improves the spotting performance even further.

Micro-expressions are facial movements that are extremely short and not easily detected, which often reflect the genuine emotions of individuals. Micro-expressions are important cues for understanding real human emotions and can be used for non-contact non-perceptual deception detection, or abnormal emotion recognition. It has broad application prospects in national security, judicial practice, health prevention, clinical practice, etc. However, micro-expression feature extraction and learning are highly challenging because micro-expressions have the characteristics of short duration, low intensity, and local asymmetry. In addition, the intelligent micro-expression analysis combined with deep learning technology is also plagued by the problem of small samples. Not only is micro-expression elicitation very difficult, micro-expression annotation is also very time-consuming and laborious. More importantly, the micro-expression generation mechanism is not yet clear, which shackles the application of micro-expressions in real scenarios. FME'22 is the inaugural workshop in this area of research, with the aim of promoting interactions between researchers and scholars from within this niche area of research and also including those from broader, general areas of expression and psychology research. The complete FME'22 workshop proceedings are available at: https://dl.acm.org/doi/proceedings/10.1145/3552465.

Facial micro-expressions (MEs) are involuntary movements of the face that occur spontaneously when a person experiences an emotion but attempts to suppress or repress the facial expression, typically found in a high-stakes environment. Unfortunately, the small sample problem severely limits the automation of ME analysis. Furthermore, due to the brief and subtle nature of ME, ME spotting is a challenging task, and the performance is still not satisfactory yet. This challenge focuses on two tasks, i.e., the micro- and macro-expression spotting task, and the ME Generation task.

Facial expression spotting is the preliminary step for micro- and macro-expression analysis. The task of reliably spotting such expressions in video sequences is currently unsolved. Current best systems depend upon optical flow methods to extract regional motion features, before categorisation of that motion into a specific class of facial movement. Optical flow is susceptible to drift error, which introduces a serious problem for motions with long-term dependencies, such as high frame-rate macro-expression. We propose a purely deep learning solution which, rather than tracking frame differential motion, compares via a convolutional model, each frame with two temporally local reference frames. Reference frames are sampled according to calculated micro- and macro-expression duration. As baseline for MEGC2021 using leave-one-subject-out evaluation method, we show that our solution performed better in a high frame-rate (200 fps) SAMM long videos dataset (SAMM-LV) than a low frame-rate (30 fps) (CAS(ME)2) dataset. We introduce a new unseen dataset for MEGC2022 challenge (MEGC2022-testSet) and achieves F1-Score of 0.1531 as baseline result.

Facial micro-expressions (FMEs) are involuntary facial movements that occur spontaneously when a person experiences an emotion but tries to suppress or repress the facial expression and usually occur in high-risk situations. Thus, FMEs are very short in duration, an important feature that distinguishes them from ordinary facial expressions. And MEs are considered to be one of the most valuable cues for complex human emotion understanding and lie detection. Since 2014, the computational analysis and automation of MEs have been an emerging area of face research. The workshop will explore various dimensions of the human mind through emotion understanding and FME analysis, as well as extended research based on multi modal approaches.

Micro-expression spotting is a fundamental step in the micro-expression analysis. This paper proposes a novel network based convolutional neural network (CNN) for spotting multi-scale spontaneous micro-expression intervals in long videos. We named the network as Micro-Expression Spotting Network (MESNet). It is composed of three modules. The first module is a 2+1D Spatiotemporal Convolutional Network, which uses 2D convolution to extract spatial features and 1D convolution to extract temporal features. The second module is a Clip Proposal Network, which gives some proposed micro-expression clips. The last module is a Classification Regression Network, which classifies the proposed clips to micro-expression or not, and further regresses their temporal boundaries. We also propose a novel evaluation metric for spotting micro-expression. Extensive experiments have been conducted on the two long video datasets: CAS(ME)2and SAMM, and the leave-one-subject-out cross-validation is used to evaluate the spotting performance. Results show that the proposed MESNet effectively enhances the F1-score metric. And comparative results show the proposed MESNet has achieved a good performance, which outperforms other state-of-the-art methods, especially in the SAMM dataset.

This paper presents baseline results for the Third Facial Micro-Expression Grand Challenge (MEGC 2020). Both macro-and micro-expression intervals in CAS(ME)2and SAMM Long Videos are spotted by employing the method of Main Directional Maximal Difference Analysis (MDMD). The MDMD method uses the magnitude maximal difference in the main direction of optical flow features to spot facial movements. The single-frame prediction results of the original MDMD method are post-processed into reasonable video intervals. The metric F1-scores of baseline results are evaluated: for CAS(ME)2, the F1-scores are 0.1196 and 0.0082 for macro-and micro-expressions respectively, and the overall F1-score is 0.0376; for SAMM Long Videos, the F1-scores are 0.0629 and 0.0364 for macro-and micro-expressions respectively, and the overall F1-score is 0.0445. The baseline project codes are publicly available at https://github.com/HeyingGithub/ Baseline-project-for-MEGC2020_spotting.

The recent emergence of automatic facial micro-expression analysis has attracted a lot of attention in the last five years. Compared to the advances made in micro-expression recognition, the task of micro-expression spotting from long videos is tremendously in need of more effective methods. This paper summarises the 3rd Facial Micro-Expression Grand Challenge (MEGC 2020) held in conjunction with the 15th IEEE Conference on Automatic Face and Gesture Recognition (FG) 2020. In this workshop, we propose a new challenge of spotting both macro- and micro-expressions from long videos, to spur the community to develop new techniques for micro-expression spotting and also to extend facial micro-expression analysis to more complex real-world scenarios where micro-expressions are likely to be intertwined among normal expressions. In this paper, we outline the evaluation protocols for the challenge task, and describe the datasets involved. Then, we summarize the methods from the accepted challenge papers, present the comparison and analysis of results, as well as future directions.

In this paper, we aim to construct a spotting framework automatically. It is still a great challenge to spot micro-expression(ME) intervals accurately due to short duration, low intensity, and shaking. Under the uncontrolled condition, the transformation is caused by head shaking. In order to remove the global movement caused by head shaking, we propose a simple yet effective method to disentangle local movement vector from the global optical flow field by the estimation of mean optical flow in the nose region. After preprocessing, we extract the completed specific pattern(SP) of ME in each region of interest(ROI). The pattern consists of two sub-patterns: magnitude and angle. However, influenced by frame rate and different intensities of micro- and macro- expressions, we propose to use a multi-scale filter to improve the ability to spot both micro- and macro-expressions. The spotting result performed on $CAS(ME)^{2}$ and SAMM shows that our proposed method outperforms the basline method.

This paper presents two methods for the first Micro-Expression Spotting Challenge 2019 by evaluating local temporal pattern (LTP) and local binary pattern (LBP) on two most recent databases, i.e. SAMM and CAS(ME)2. First we propose LTP-ML method as the baseline results for the challenge and then we compare the results with the LBP-χ2-distance method. The LTP patterns are extracted by applying PCA in a temporal window on several facial local regions. The micro-expression sequences are then spotted by a local classification of LTP and a global fusion. The LBP-χ2-distance method is to compare the feature difference by calculating χ2distance of LBP in a time window, the facial movements are then detected with a threshold. The performance is evaluated by Leave-One-Subject-Out cross validation. The overlap frames are used to determine the True Positives and the metric F1-score is used to compare the spotting performance of the databases. The F1-score of LTP-ML result for SAMM and CAS(ME)2are 0.0316 and 0.0179, respectively. The results show our proposed LTP-ML method outperformed LBP-χ2-distance method in terms of F1-score on both databases.

Automatic facial micro-expression (ME) analysis is a growing field of research that has gained much attention in the last five years. With many recent works testing on limited data, there is a need to spur better approaches that are both robust and effective. This paper summarises the 2nd Facial Micro-Expression Grand Challenge (MEGC 2019) held in conjunction with the 14th IEEE Conference on Automatic Face and Gesture Recognition (FG) 2019. In this workshop, we proposed challenges for two micro-expression (ME) tasks- spotting and recognition, with the aim of encouraging rigorous evaluation and development of new robust techniques that can accommodate data captured across a variety of settings. In this paper, we outline the evaluation protocols for the two challenge tasks, the datasets involved, and an analysis of the best performing works from the participating teams, together with a summary of results. Finally, we highlight some possible future directions.

The Micro-expressions (MEs) carry specific nonverbal information, for example the facial movement caused by pain. However, as a consequence of their local and short nature, it is difficult to detect MEs. This paper presents a novel detection method by recognizing a local and temporal pattern (LTP) of facial movement. In our system, with the purpose of improving the detection accuracy, temporal local features are generated from the video in a sliding window of 300ms (mean duration of a ME). These features are extracted from a projection in PCA space and form a specific pattern during ME which is the same for all MEs. Using a classical classification algorithm (SVM), MEs are then distinguished from other facial movements. Finally, a global fusion analysis is applied on the whole face to eliminate false positives. Experiments are performed on two databases: CASME I and CASME II. The detection results show that the proposed method outperforms the most popular detection method in terms of F1-score according to the analysis of multiple metrics.