Psychological variables in the control of brain-computer interfaces

BCI (Brain-Computer Interface) is a system that allows interaction between the human brain and a computer. It is based on analyzing electroencephalographic signals (EEG) and processing them to generate control commands. The study analyzed the possible influence of psychological variables, such as the imaginative kinesthetic capacity and anxiety, in relation to performance in a BCI. All participants (4 male and 19 female students) completed the questionnaires and carried out a session of BCI to control their EEG signals in a virtual setting of a car along a straight road. The group was divided into two subgroups according to their EEG signals or differential responses obtained in the left-right discrimination. Study results showed no significant differences in cognitive variables of imagination or in anxiety. By comparing the degree of participants' BCI control, a new quantitative parameter for comparing performances and making decisions in signal processing was found. The findings, the ongoing research process to refine the control of a BCI, and the interaction of psychological and computer procedures are discussed.     

单侧化准备电位的含义和应用

单侧化准备电位（Lateralized readiness potential, LRP）是指在随意运动中,反应效应器方位所对应的对侧大脑皮层出现的准备电位。LRP分析的关键是确定启动时间点。LRP可以揭示刺激-反应不同阶段的认知加工时间特性。可以从反应准备的抽象性或具体性以及大脑控制运动输出的“中枢”机制或“外周”机制这两个思路去验证LRP。LRP在阈下知觉和内隐学习、运动准备和反应执行、西蒙效应等方面的认知心理学研究以及新兴的脑-机界面工程心理学研究得到了广泛的应用,但LRP的应用存在着某些限制因素,如：脑电干扰、测量的低信噪比和其本身对反应效应器的要求等     

An optimized facial stimuli paradigm for hybrid SSVEP+P300 brain computer interface

In this paper, hybrid BCI that merges Event Related Potentials (P300) and Steady State visual Evoked Potentials (SSVEP) simultaneously is proposed to enhance the performance of Four-choice command system. Here we integrate human facial structure in external visual stimulus to evoke stronger cortical responses in hybrid SSVEP+P300 BCI & compare it with non-face stimuli. We also addressed question of feasibility of eliciting one potential by face & other by non-face stimuli. To evoke SSVEP & P300 responses, paradigms with non-face stimuli, neutral face stimuli, and facial expression changes stimuli are proposed. We also projected additional paradigm where SSVEP is elicited by non-face and P300 by flashing different facial expressions. Results proved the last paradigm evoke stronger cortical potentials and thereby improve system accuracy and ITR than other paradigms. Author discussed external stimulus parameters that might affect simultaneous evocation of multiple brain potentials and their deterioration effect on individual potentials.     

Emotion perception and recognition: An exploration of cultural differences and similarities

The electroencephalogram (EEG) is a powerful method for investigation of different cognitive processes. Recently, EEG analysis became very popular and important, with classification of these signals standing out as one of the mostly used methodologies. Emotion recognition is one of the most challenging tasks in EEG analysis since not much is known about the representation of different emotions in EEG signals. In addition, inducing of desired emotion is by itself difficult, since various individuals react differently to external stimuli (audio, video, etc.). In this article, we explore the task of emotion recognition from EEG signals using distance-based time-series classification techniques, involving different individuals exposed to audio stimuli. Furthermore, since some of the participants in the experiment do not understand the language of the stimuli, we also investigate the impact of language understanding on emotion perception. Using time-series distances as features for the construction of new data representations, applied here for the first time to emotion recognition and related tasks, lead to excellent classification performance, indicating that differences between EEG signals can be used to build successful models for recognition of emotions, individuals, and other related tasks. In the process, we observed that cultural differences between the subjects did not have a significant impact on the recognition tasks and models.     

Cognition and affective style: Individual differences in brain electrical activity during spatial and verbal tasks

Relations between brain electrical activity and performance on two cognitive tasks were examined in a normal population selected to be high on self-reported measures of Positive or Negative Affectivity. Twenty-five right-handed women, from an original pool of 308 college undergraduates, were the participants. EEG was recorded during baseline and during psychometrically matched spatial and verbal tasks. As predicted, participants who were high in Positive Affectivity performed equally well on the verbal and spatial tasks, while participants who were high in Negative Affectivity had spatial scores that were lower than their verbal scores. There were no group differences in baseline EEG. Both groups exhibited left central activation (i.e., alpha suppression) during the verbal and spatial tasks. When EEG data were analyzed separately for the group high in Positive Affectivity, there was evidence of parietal activation for the spatial task relative to the verbal task. The EEG data for the group high in Negative Affectivity had comparable EEG power values during verbal and spatial tasks at parietal scalp locations. These data suggest that, within a selected normal population, differences in affective style may interact with cognitive performance and with the brain electrical activity associated with that performance.     

自我关注重评和情境关注重评情绪调节策略及对随后认知控制的影响

认知重评作为高度适应性的情绪调节策略, 是否消耗随后任务所需的认知资源仍存在争议。以往研究把重评作为单一策略研究, 并未区分重评亚型对这一问题进行探索。本研究采用情绪调节与认知控制结合的任务, 考察自我关注和情境关注两种重评亚型调节情绪的效果, 以及对随后认知控制的影响是否存在差异。结果发现两种重评策略都能有效调节情绪, 但调节效果存在差异。从行为角度看, 与中性刺激相比, 负性刺激会引发更高的负性情绪水平, 对随后冲突任务的认知控制能力更差。进一步从神经机制水平来看, 增加负性情绪可能会进一步消耗随后任务可用的认知资源, 与自我关注重评相比, 采用情境关注重评降低负性情绪后, 对随后冲突任务的认知控制能力更强。说明两种重评亚型并不同质, 不仅在调节情绪的效果上存在差异, 而且会引发不同的认知控制后果; 同时, 负性情绪水平越高, 认知控制能力可能会越差。     

A functional approach for research on cognitive control: Analysing cognitive control tasks and their effects in terms of operant conditioning

Cognitive control is an important mental ability that is examined using a multitude of cognitive control tasks and effects. The present paper presents the first steps in the elaboration of a functional approach, which aims to uncover the communalities and differences between different cognitive control tasks and their effects. Based on the idea that responses in cognitive control tasks qualify as operant behaviour, we propose to reinterpret cognitive control tasks in terms of operant contingencies and cognitive control effects as instances of moderated stimulus control. We illustrate how our approach can be used to uncover communalities between topographically different cognitive control tasks and can lead to novel questions about the processes underlying cognitive control.     

Anxiety, perception, and control of heart rate

8 women and 8 men took Cattell's IPAT-anxiety questionnaire and later McFarland's test of ability to perceive heart activity. The second test involved subjects' tracking their own heart rates, then they enrolled in an EKG biofeedback session to evaluate ability to increase and decrease heart rate from subjects' resting baselines. At the end of the session each subject completed Blanchard, et al.'s questionnaire to specify the cognitive strategies used for heart-rate control. Heart rate, abdominal respiration rate, respiration amplitude, EEG percent power in theta, alpha, and beta bands were evaluated. Success of heart-rate decrease seemed to depend mainly on activity levels: the subjects who achieved high scores on the activity test decreased heart rate significantly better than did low scorers. The relationship between scores for perception of heart and increases in heart rate was nonsignificant: increased heart-rate seemed to depend on differences in respiration between the rest and periods of increase. The significant, negative correlation between trait anxiety and perceptions of heart activity suggested that anxiety affected subjects' ability to perceive heart rate. The theta EEG power of the right hemisphere was significantly higher in subjects scoring high than for those low in perception of heart activity. During heart-rate increase tasks subjects mainly reported use of 'arousal responses,' similarly during heart-rate decrease tasks they reported use of relaxation responses.     

Design and operation of an EEG-based brain-computer interface with digital signal processing technology

We are developing an electroencephalographic (EEG)-based brain-computer interface (BCI) system that could provide an alternative communication channel for those who are totally paralyzed or have other severe motor impairments. The essential features of this system are as follows: (1) EEG analysis in real time, (2) real-time conversion of that analysis into device control, and (3) appropriate adaptation to the EEG of each user. Digital signal processing technology provides the speed and flexibility needed to satisfy these requirements. It also supports evaluation of alternative analysis and control algorithms, and thereby facilitates further BCI development.     

Hybrid route choice model incorporating latent cognitive effects of real-time travel information using physiological data

The proliferation of information systems is enabling drivers to receive en route real-time travel information, often from multiple sources, for making informed routing decisions. A robust understanding of route choice behavior under information provision can be leveraged by traffic operators to design information and its delivery systems for managing network-wide traffic. However, most existing route choice models lack the ability to consider the latent cognitive effects of information on drivers and their implications on route choice decisions. This paper presents a hybrid route choice modeling framework that incorporates the latent cognitive effects of real-time information and the effects of several explanatory variables that can be measured directly (i.e., route characteristics, information characteristics, driver attributes, and situational factors). The latent cognitive effects are estimated by analyzing drivers’ physiological data (i.e., brain electrical activity patterns) measured using an electroencephalogram (EEG). Data was collected for 95 participants in driving simulator experiments designed to elicit realistic route choices using a network-level setup featuring routes with different characteristics (in terms of travel time and driving environment complexity) and dynamic ambient traffic. Averaged EEG band powers in multiple brain regions were used to extract two latent cognitive variables that capture driver’s cognitive effort during and immediately after the information provision, and cognitive inattention before implementing the route choice decision. A Multiple Indicators Multiple Causes model was used to test the effects of several explanatory factors on the latent cognitive variables, and their combined impacts on route choice decisions. The study results highlight the significant effects of driver attributes and information characteristics on latent cognitive effort and of route characteristics on latent cognitive inattention. They also indicate that drivers who are more attentive and exert more cognitive effort are more likely to switch from their current route by complying with the information provided. The study insights can aid traffic operators and information service providers to incorporate human factors and cognitive aspects while devising strategies for designing and disseminating real-time travel information to influence drivers’ route choices.     

EEG波形伪迹去除方法

EEG波形记录与ERP分析技术是认知科学和脑科学研究的新兴手段 ,但在实际研究和临床应用中 ,伪迹一直是困扰研究效度的重要因素。本文主要介绍了近年来兴起的回归方法、伪迹减法、主成分分析 (PCA)、独立成分分析 (ICA)、JADE分析等脑电伪迹去除技术。相对于传统方法 ,这些技术存在精度高、速度快、实用性强的优点 ,但它们都各自针对不同问题情境 ,均建立在特定假设基础上 ,所以应根据具体的研究目的和实验条件进行合理选择。通用性、实时性和稳定性将是伪迹去除技术的发展方向     

工作记忆刷新及其训练效应——经颅直流电刺激的作用

工作记忆刷新是执行功能的重要成分之一。以往研究结合n-back任务和经颅直流电刺激（transcranial direct current stimulation ,tDCS）技术探究刷新能力,发现tDCS技术能够一定程度上增强刷新训练效果并引起大脑神经元相关活动的变化,其增强效果能够维持一定的时间,且能够迁移到其他认知任务之中。但tDCS的干预效果在各项研究中存在一定的差异性。其作用效果会受到训练任务与训练方式、电流强度、电极布局和训练时间间隔等因素的影响。未来研究可以探索tDCS结合刷新训练的最佳刺激参数,以获得最优化的干预效果。     

Age-related qualitative differences in post-error cognitive control adjustments

Detecting an error signals the need for increased cognitive control and behavioural adjustments. Considerable development in performance monitoring and cognitive control is evidenced by lower error rates and faster response times in multi-trial executive function tasks with age. Besides these quantitative changes, we were interested in whether qualitative changes in balancing accuracy and speed contribute to developmental progression during elementary school years. We conducted two studies investigating the temporal and developmental trajectories of post-error slowing in three prominent cognitive conflict tasks (Stroop, Simon, and flanker). We instructed children (8-, 10-, and 12-year-old) and adults to respond as fast and as accurately as possible and measured their response times on four trials after correct and incorrect responses to a cognitive conflict. Results revealed that all age groups had longer response times on post-error versus post-correct trials, reflecting post-error slowing. Critically, slowing on the first post-error trial declined with age, suggesting an age-related reduction in the orienting response towards errors. This age effect diminished on subsequent trials, suggesting more fine-tuned cognitive control adjustments with age. Overall, the consistent pattern across tasks suggests an age-related change from a relatively strong orienting response to more balanced cognitive control adaptations.     

Hemispheric lateralization of the EEG during wakefulness and REM sleep in young healthy adults

EEG recordings confirm hemispheric lateralization of brain activity during cognitive tasks. The aim of the present study was to investigate spontaneous EEG lateralization under two conditions, waking and REM sleep. Bilateral monopolar EEG was recorded in eight participants using a 12-electrode montage, before the night (5 min eyes closed) and during REM sleep. Spectral analysis (0.75-19.75 Hz) revealed left prefrontal lateralization on total spectrum amplitude power and right occipital lateralization in Delta activity during waking. In contrast, during REM sleep, right frontal lateralization in Theta and Beta activities and right lateralization in occipital Delta activity was observed. These results suggest that spontaneous EEG activities generated during waking and REM sleep are supported in part by a common thalamo-cortical neural network (right occipital Delta dominance) while additional, possibly neuro-cognitive factors modulate waking left prefrontal dominance and REM sleep right frontal dominance.     

Quantitative EEG Assessment During Neuropsychological Task Performance in Adults with Attention Deficit Hyperactivity Disorder

This study evaluated the neuropsychological performance of adults with and without Attention Deficit Hyperactivity Disorder (ADHD) during the Paced Auditory Serial Addition Test (PASAT), Wisconsin Card Sorting Test: Computerized Version 3 (WCST), and the Integrated Visual and Auditory Continuous Performance Test (IVA). Quantitative electroencephalographic (QEEG) data were also collected during task performance to examine differences in cortical activity between groups and tasks. Results suggest that adults with ADHD demonstrated lower levels of performance on the PASAT and IVA, tasks that involve working memory and processing speed, and sustained attention, respectively. Adults with ADHD also had more upper alpha activity during the IVA. Lastly, for the ADHD group, an increased theta/beta ratio during the IVA was significantly related to poorer attentional performance. The current results support reinforcing specific types of cortical activity though EEG operant conditioning (neurofeedback) as a treatment option in adults with ADHD. This paper is based largely in part on a dissertation by J. Noland White in partial fulfillment of the requirements of his doctoral program at The University of Tennessee. Portions of this study have been presented in summary form at several professional conferences.     

Creative ways to well-being: Reappraisal inventiveness in the context of anger-evoking situations

Neuroscientific studies in the field of creativity mainly focused on tasks drawing on basic verbal divergent thinking demands. This study took a step further by investigating brain mechanisms in response to other types of creative behavior, involving more “real-life” creativity demands in the context of emotion regulation and well-being. Specifically, functional patterns of EEG alpha activity were investigated while participants were required to generate as many and as different ways as possible to reappraise presented anger-eliciting situations in a manner that reduces their anger. Cognitive reappraisal involves some of the same cognitive processes as in conventional verbal creativity tasks, inasmuch as it requires an individual to inhibit or disengage from an emotional event, to shift attention between different perspectives, and to flexibly adopt new solutions. To examine whether alpha oscillations during cognitive reappraisal are different from those during conventional creative ideation, the EEG was also assessed during performance of the Alternative Uses task, requiring individuals to generate as many and as original uses of an object as possible. While cognitive reappraisal was associated with a similar pattern of alpha power as observed in conventional verbal creative ideation, the former yielded significantly stronger alpha power increases at prefrontal sites, along with lower alpha increases at more posterior cortical sites, indicating higher cognitive control and less spontaneous imaginative thought processes in the generation of effective strategies to regulate an ongoing negative emotional state.     

创造性思维的脑机制

创造性思维是创造性的核心。近年来,脑电和脑成像技术的发展为研究创造性思维的神经基础提供了有力的技术支持,对创造性思维的脑机制研究取得了较大进展。创造性思维的脑机制研究主要包括顿悟的脑机制、发散性思维的脑机制、远距离联想的脑机制、言语创造性和图画创造性的对比的脑机制研究。研究结果显示创造性思维需要多个脑区的参与,因不同的认知任务其关键脑区而有所不同。对创造性思维的脑机制研究进行了总结,对这些研究可能存在创造性思维究竟应该定义为“领域一般的”还是“领域特殊的”的解释进行了讨论,并指出了研究中可能存在的基线任务设置问题和未来研究中需要在研究手段、研究设计、研究领域等方面加以改进的建议     

Using microcomputer-based eeg to enable and encourage student-designed projects

Microcomputer-based electrophysiological recording systems enhance undergraduates’ understanding of neural activity and enable them to design independent research projects. The physiological psychology class at Alma College has employed BIOPAC Systems MP100 hardware with Acq-Knowledge software and Macintosh computers to record and analyze electroencephalograms (EEG). After examining progressive changes in brain waves during sleep, student researchers have proceeded to study the effects of a variety of factors such as caffeine, cognitive tasks, and prior experiences. The simplicity of the system allows undergraduates to concentrate on experimental design and data analysis rather than instrumentation.     

眼动与脑电同步记录技术在心理语言学研究中的新进展

传统的心理语言学研究手段存在一定的弊端,眼动和脑电同步记录技术具有高时间和高空间分辨率的特性,能够在自然阅读情境下探讨人在阅读中认知加工的时间进程及其相应的神经机制。本文在阐述眼动与脑电同步记录的必要性和方法的基础上,较为全面地介绍了近10年来同步记录技术在心理语言学研究中的新进展,并对该技术的应用前景进行了展望,以期对国内从事心理语言学领域的研究者有一定的启示。     

Cognitive control of a simple mental image in patients with obsessive--compulsive disorder

The nature of obsessions has led researchers to try to determine if the main problem in obsessive-compulsive disorder (OCD) is impaired inhibitory control. Previous studies report that the effort to suppress is one of the factors that increase the frequency of obsessive thoughts. Based on these results and those of the present study that suggest inferior parietal lobe (IPL) abnormality in OCD and findings of a recent study that reported the importance of the right posterior parietal cortex in cognitive control of a simple mental image, the present cognitive control paradigm study aimed to determine whether there is a difference in brain dynamics between OCD patients and non-obsessive controls while performing tasks that necessitate cognitive control of a simple mental image, and whether the right posterior parietal region is one of the regions in which a difference in activity between the OCD patients and controls would be observed. Functional brain imaging was performed while the participants attempted to suppress, imagine, or manipulate a mental image. The general linear model showed that there was a main effect of group and main effect of task. Accordingly, in all contrasts (suppression minus free-imagination, erasing minus free-imagination, and imagination minus free-imagination), the right IPL, right posterior cingulate cortex, and right superior frontal gyrus activity were lower in the OCD patients than in the healthy controls. These results and the observed correlations between activity levels, and symptom and subjective performance scores are discussed. In conclusion, the results of the present study and those of previous studies suggest that the main problem in OCD might be difficulty activating the right frontoparietal networks during tasks that require cognitive control, which might result in the intrusiveness of obsessive thoughts.