自闭症谱系障碍个体的注意解离

注意解离是注意定向网络的重要组成部分, 指在注意转移过程中对原来刺激进行注意分离的过程。自闭症个体注意解离的早期受损会直接影响其它重要功能的发展, 尤其是唤醒调节和共同注意发展。采用间隙重叠范式的研究发现, 自闭症个体注意解离能力是否异常还存在争议, 被试年龄及取样、测量指标和刺激特征可能是影响的因素; 其神经机制可能涉及额叶、顶叶、小脑和胼胝体等脑区。未来应从脑机制研究入手, 综合考虑被试特征、研究方法和刺激特征对注意解离结果的影响, 明确其在自闭症早期预测和识别中的作用。     

抑郁患者的注意偏向

抑郁患者的注意偏向是抑郁认知研究中的重要问题。该文从研究范式、注意偏向特点及理论解释等方面进行了探讨,在研究范式上有Stroop范式、点探测任务和线索–靶子范式等,在抑郁患者注意偏向的特点上有对象为临床患者、需要阈上刺激、刺激内容针对抑郁患者和刺激强度不能太弱等,在理论解释上有注意成分、注意聚焦变窄、认知负荷和唤醒水平等,并对将来的研究方向进行了探讨     

哭泣表情面孔的注意偏向:眼动的证据

研究采用双选择Oddball范式和线索-靶子范式,并结合眼动技术,以微笑、哭泣和中性表情面孔为刺激材料,综合考察哭泣表情面孔在识别和解离过程中的注意偏向。研究发现:在识别阶段,哭泣表情面孔的识别正确率和反应速度都显著优于微笑表情面孔,进一步的兴趣区注视偏向分析发现,哭泣和微笑表情面孔的注视模式既具有一致的规律,又存在细微的差异;在解离阶段,返回抑制受线索表情类型的影响,在有效线索条件下,哭泣表情线索呈现后个体对目标刺激的平均注视时间和眼跳潜伏期都显著短于其它表情线索。表明哭泣表情面孔在识别和解离过程中具有不同的注意偏向表现,在识别阶段表现为反应输出优势和注视模式上的一致性与差异性;在解离阶段表现为有效线索条件下,对目标刺激定位和视觉加工的促进作用。     

自闭症儿童视觉动态信息的注意加工特点——来自多目标追踪任务的证据

为了考察中低功能自闭症儿童在动态条件下的多目标注意加工特点,研究采用多目标追踪实验范式,具体追踪任务采用多目标随机运动和碰撞反弹算法。实验设计为两因素混合设计,组间变量为年龄和性别匹配的中低功能自闭症和正常儿童组,组内变量为追踪目标数量（分别为1、2、3、4个目标）,因变量为被试在多目标追踪任务中的追踪正确率和追踪容量。结果发现：（1）中低功能自闭症儿童在目标数量为1到目标数量为4时的正确率均明显低于正常儿童,且标准差变异较大,中低功能自闭症儿童的多目标的持续追踪能力和稳定性存在一定的缺陷;（2）当目标数量为1时,正常组儿童与中低功能自闭症儿童的追踪容量差异不显著;目标为2、3、4时,两组追踪容量差异均显著。不同目标数量情况下中低功能自闭症儿童平均的注意容量为0.83~1.24个（平均容量约为1个）明显低于正常儿童的0.95~3.72个（最大容量接近4个）。中低功能自闭症儿童在多目标追踪上表现为单焦点注意加工的特点,存在一定程度的注意转移缺陷。     

孤独症谱系障碍者情绪躯体语言的注意偏向

情绪躯体语言是在社交场合中传递情绪信息的典型非字面语言形式,包含重要社交信息。本研究从注意偏向角度考察孤独症个体的情绪躯体语言加工特点和认知机制。实验1采用点探测范式向被试呈现高兴、愤怒、恐惧、悲伤情绪躯体语言图片,考察孤独症个体的注意偏向特点。结果显示孤独症组未表现出对某类情绪躯体语言的注意偏向。实验2进一步采用生态效度更高的自由浏览范式考察孤独症组对情绪躯体语言图片的眼动特点。结果显示孤独症组对悲伤躯体语言注意回避,对高兴躯体语言注意增强和注意解离困难。结果表明,孤独症个体对不同类型的情绪躯体语言的注意偏向特征不同。自由浏览范式对于识别孤独症情绪躯体语言的注意偏向特点具有较高的灵敏性。     

返回抑制实验范式的衍变及其理论贡献

返回抑制是指对原先注意过的客体或位置进行反应时所表现出的滞后现象,其基础实验范式是由Posner和Cohen在研究视觉空间注意的实验中发现的,后续该范式及理论被广泛运用并在近年来被研究者们不断延伸探索和推进。范式及理论的推进具体表现在以下几个方面：(1)返回抑制基础实验范式新进展：在线索-靶子范式中形成感觉运动任务、在线索或靶子中引入图片材料、视听靶子同时出现的双通道注意研究;(2)返回抑制范式与其他范式的结合：包括与Stroop任务、Go/No-go任务、Simon任务、隧道任务等结合;(3)返回抑制范式与具体情景的结合：如社会情景、体育运动情景;(4)返回抑制范式与其他新技术的结合：与三维虚拟现实、眼动、事件相关电位、功能性磁共振成像和经颅磁技术等结合。综上所述,近年来关于返回抑制范式的研究已经取得了诸多成果,相关理论成果也在不断地推进,未来可以从返回抑制范式生态学效度的提高、返回抑制范式与认知训练的结合以及返回抑制范式与多种新技术的结合等多个方面予以拓展。     

眼跳的研究范式及其主要认知功能

眼跳运动系统为研究者探索行为的认知控制机制提供了有力工具。已有研究发现,很多认知过程会影响不同类型眼跳任务中的眼跳参数。在系统梳理已有研究的基础上,从以下4个方面系统阐述和评价了眼跳运动的研究范式和主要认知功能：（1）视觉导向眼跳的研究范式和变式及其认知功能,包括空白/重叠效应、分心物效应、提示效应、学习效应等;（2）预测性眼跳的研究范式和认知控制,涉及神经生物钟理论、视空间工作记忆、指导语等;（3）记忆导向眼跳的研究范式和变式及其认知控制,包括分心物效应、年龄效应、视空间工作记忆的抑制效应、注意等;（4）反向眼跳的研究范式和变式及其认知控制,包括反向眼跳抑制、眼跳决策信号竞争整合模型、工作记忆容量、注意、错误监控、学习、奖励和年龄效应等。最后,结合已有研究范式对未来眼跳研究的趋势和需解决的问题进行了展望。     

自闭症幼儿自主性共同注意的实验研究

为探索和发现自闭症幼儿的自主性共同注意的特征,以6名自闭症幼儿,以及在心理年龄与之匹配的弱智和正常儿童各6名作为研究对象,以实验和准实验的方法,进行此研究。同时还以秒为单位对实验过程与结果进行编码分析。结果表明,自闭症幼儿的自主性视觉方向所及目标物多于人,而人的目标中叉更多地锁定同伴而非教师。自闭症幼儿在唤起他人共同注意时多以“拉”和“抱”来替代指点行为。自主性共同注意的发生率与情绪有密切关系。     

视觉空间注意的定向/重定向

基于位置的注意理论认为注意分布是以特定的空间位置或区域为基础,该理论认为,被试根据任务要求,注意焦点可以像聚光灯一样移动、注意范围可以像变焦镜头一样进行缩放以及注意在焦点处集中程度最高,并向四周逐渐扩散。自Posner提出这一理论以来,近30年研究者们对视觉空间的注意定向/重定向开展了大量的研究。本文对此进行了综述,一方面包括注意定向/重定向的范式、类型;另一方面包括由此产生的早期易化和晚期抑制效应以及未来研究展望。     

胖负面身体自我女大学生对胖信息的注意偏好:注意警觉还是注意维持

本研究对已有负面身体自我个体注意偏好研究采用的实验范式的问题进行了分析,提出胖负面身体自我个体对胖相关信息的注意偏向存在的另一种可能,即胖负面身体自我个体对胖相关信息可能存在注意维持时间更长的假设。共设计了3个实验对假设进行验证。实验1a采用线索范式研究高胖负面身体自我个体对胖相关词语的注意警觉和注意维持,线索目标SOA为300ms,实验1b采用同样的实验范式,只是将实验材料变为更具直接意义的身体轮廓图。两个实验的结果均支持实验假设,但是未能排除反应准备和线索对目标产生掩蔽等因素的影响。因此,实验2在身体和花瓶轮廓图周围呈现字母,要求被试对字母进行辨认,对被试的注意维持成分进行直接的测量。结果验证了高胖负面身体自我女大学生对胖身体轮廓图注意维持时间更长。综合几个实验的结果,得到以下结论:在本实验条件下,胖负面身体自我女大学生对胖身体信息的注意偏差成分是注意维持时间更长。     

孤独症谱系障碍者视觉定向与视觉搜索的特点及神经机制

定向网络是注意网络的重要组成部分, 主要包括视觉定向与视觉搜索两大任务。对于这两大注意任务, 正常个体在神经机制上存在较大的重叠, 然而, 孤独症个体却表现出截然相反的行为证据。研究者从非社会信息的注意视角发现, 一般而言, 在视觉定向上, 孤独症个体注意转移不存在缺陷, 而注意脱离存在困难, 但该结论仍有争议; 在视觉搜索上, 孤独症个体存在视觉搜索优势, 但该优势发生的阶段及原因仍需进一步探究。未来研究应进一步考察孤独症个体在视觉定向任务中左右视野的不对称性、视觉搜索优势的内在机制及两大注意任务之间的相互关系。     

Presaccadic attention allocation and express saccades

Express saccades are visually-guided saccades that are characterized by an extremely short latency of about 100 ms. The present experiments tested the hypothesis that a disengagement of visual attention is necessary for the generation of express saccades. All subjects produced large numbers of express saccades in the gap paradigm, in which the fixation stimulus is removed 200 ms before target onset (Exp. 1), but not in the overlap paradigm, in which the fixation stimulus remains on during the entire trial (Exp. 2). By means of peripheral cues (Exps. 3–5) and central cues (Exps. 6–7), visual attention was directed at the target location for the saccade before the actual appearance of the saccade target. In all experiments, the location cues facilitated rather than abolished express saccades. The generation of express saccades was facilitated even when the currently fixated visual stimulus was not removed before target onset (fixation-overlap; Exps. 5–7). The results are explained by the hypothesis that a disengagement of a separate fixation system is necessary for the generation of express saccades, a hypothesis that is in line with current neurobiological findings.     

Influence of the environment on the early development of attentional control

The control of visual attention is key to learning and has a foundational role in the development of self-regulated behavior. Basic attention control skills emerge early in life and show a protracted development along childhood. Prior research suggests that attentional development is influenced by environmental factors in early and late childhood. Although, much less information is available about the impact of the early environment on emerging endogenous attention skills during infancy. In the current study we aimed to test the impact of parental socioeconomic status (SES) and home environment (chaos) in the emerging control of orienting in a sample of typically-developing infants. A group of 142 (73 female) 6-month-old infants were longitudinally tested at 6, 9 (n = 122; 60 female) and 16–18 (n = 91; 50 female) months of age using the gap-overlap paradigm. Median saccade latency (mdSL) and disengagement failure (DF) were computed as dependent variables for both overlap and gap conditions. Also, composite scores for a Disengagement Cost Index (DCI) and Disengagement Failure Index (DFI) were computed considering mdSL and DF of each condition, respectively. Families reported SES and chaos in the first and last follow-up sessions. Using Linear Mixed Models with Maximum Likelihood estimation (ML) we found a longitudinal decrease in mdSL in the gap but not in the overlap condition, while DF decreased with age independently of the experimental condition. Concerning early environmental factors, an SES index, parental occupation and chaos at 6 months were found to show a negative correlation with DFI at 16–18 months, although in the former case it was only marginally significant. Hierarchical regression models implementing ML showed that both SES and chaos at 6 months significantly predicted a lower DFI at 16–18 months. Results show a longitudinal progression of endogenous orienting between infancy and toddlerhood. With age, an increased endogenous control of orienting is displayed in contexts where visual disengagement is facilitated. Visual orienting involving attention disengagement in contexts of visual competition do not show changes with age. Moreover, these attentional mechanisms of endogenous control seem to be modulated by early experiences of the individual with the environment.     

Unimpaired attentional disengagement in toddlers with autism spectrum disorder

A prominent hypothesis holds that ‘sticky’ attention early in life in children with autism spectrum disorder (ASD) limits their ability to explore and learn about the world. Under this hypothesis, the core clinical symptoms of ASD – restricted interests, repetitive behaviors and impaired social/communication abilities – could all result from impaired attentional disengagement during development. However, the existence of disengagement deficits in children with ASD is controversial, and a recent study found no deficit in 5‐ to 12‐year‐olds with ASD. Nonetheless, the possibility remains that disengagement is impaired earlier in development in children with ASD, altering their developmental trajectory even if the attentional deficit itself is remediated or compensated for by the time children with ASD reach school age. Here, we tested this possibility by characterizing attentional disengagement in a group of toddlers just diagnosed with ASD (age 21 to 37 months). We found strikingly similar performance between the ASD and age‐matched typically developing (TD) toddlers, and no evidence of impaired attentional disengagement. These results show that even at a young age when the clinical symptoms of ASD are first emerging, disengagement abilities are intact. Sticky attention is not a fundamental characteristic of ASD, and probably does not play a causal role in its etiology.     

Manipulating the disengage operation of covert visual spatial attention

Processes of covert visual spatial attention have been closely linked to the programming of saccadic eye movements. In particular, it has been hypothesized that the reduction in saccadic latency that occurs in the gap paradigm is due to the prior disengagement of covert visual spatial attention. This explanation has received considerable criticism. No study as yet has attempted to demonstrate a facilitation of the disengagement of attention from a covertly attended object. If such facilitation were possible, it would support the hypothesis that the predisengagement of covert attention is necessary for the generation of express saccades. In two experiments using covert orienting of visual attention tasks (COVAT), with a high probability that targets would appear contralateral to the cued location, we attempted to facilitate the disengagement of covert attention by extinguishing peripheral cues prior to the appearance of targets. We hypothesized that the gap between cue offset and target onset would facilitate disengagement of attention from a covertly attended object. For both experiments, responses to targets appearing after a gap were slower than were responses in the no-gap condition. These results suggest that the prior offset of a covertly attended object does not facilitate the disengagement of attention.     

Low-level visual attention and its relation to joint attention in autism spectrum disorder

Visual attention is integral to social interaction and is a critical building block for development in other domains (e.g., language). Furthermore, atypical attention (especially joint attention) is one of the earliest markers of autism spectrum disorder (ASD). The current study assesses low-level visual attention and its relation to social attentional processing in youth with ASD and typically developing (TD) youth, aged 7 to 18 years. The findings indicate difficulty overriding incorrect attentional cues in ASD, particularly with non-social (arrow) cues relative to social (face) cues. The findings also show reduced competition in ASD from cues that remain on-screen. Furthermore, social attention, autism severity, and age were all predictors of competing cue processing. The results suggest that individuals with ASD may be biased towards speeded rather than accurate responding, and further, that reduced engagement with visual information may impede responses to visual attentional cues. Once attention is engaged, individuals with ASD appear to interpret directional cues as meaningful. These findings from a controlled, experimental paradigm were mirrored in results from an ecologically valid measure of social attention. Attentional difficulties may be exacerbated during the complex and dynamic experience of actual social interaction. Implications for intervention are discussed.     

Deeper attentional masking by lateral objects in children with autism

Autism spectrum disorder (ASD) is often associated with a detail-oriented perception and overselective attention in visual tasks, such as visual search and crowding. These results were obtained manipulating exclusively the spatial properties of the stimuli: few is known about the spatio-temporal dynamics of visual processing in ASD. In this study we employed an attentional masking (AM) paradigm comparing children with ASD and IQ-matched typically developing (TD) controls. The AM effect refers to an impaired identification of a target followed by a competitive masking object at different proximities in space and time. We found that ASD and TD groups did not differ in the AM effect provoked by the competitive object displayed in the same position of the target. In contrast, children with ASD showed a deeper and prolonged interference than the TD group when the masking object was displayed in the lateral position. These psychophysical results suggest that the inefficient attentional selection in ASD depends on the spatio-temporal interaction between competitive visual objects. These evidence are discussed in the light of the ASD altered neural connectivity hypothesis and the reentrant theory of perception.     

Fearful faces modulate looking duration and attention disengagement in 7-month-old infants

The present study investigated whether facial expressions modulate visual attention in 7-month-old infants. First, infants' looking duration to individually presented fearful, happy, and novel facial expressions was compared to looking duration to a control stimulus (scrambled face). The face with a novel expression was included to examine the hypothesis that the earlier findings of greater allocation of attention to fearful as compared to happy faces could be due to the novelty of fearful faces in infants' rearing environment. The infants looked longer at the fearful face than at the control stimulus, whereas no such difference was found between the other expressions and the control stimulus. Second, a gap/overlap paradigm was used to determine whether facial expressions affect the infants' ability to disengage their fixation from a centrally presented face and shift attention to a peripheral target. It was found that infants disengaged their fixation significantly less frequently from fearful faces than from control stimuli and happy faces. Novel facial expressions did not have a similar effect on attention disengagement. Thus, it seems that adult-like modulation of the disengagement of attention by threat-related stimuli can be observed early in life, and that the influence of emotionally salient (fearful) faces on visual attention is not simply attributable to the novelty of these expressions in infants' rearing environment.