注意范围分布对视觉工作记忆巩固过程的影响

以往研究发现个体能够同时巩固一定数量的项目信息进入视觉工作记忆系统。本研究将考察视觉工作记忆的巩固容量是否会受到分配到记忆项目上的注意资源量的影响。实验1在同时序列掩蔽范式的基础上, 用控制记忆项目呈现区域的大小的方法操纵被试的注意范围, 从而达到操纵分配到单个项目上的注意资源量的目的。研究结果显示, 被试的记忆成绩随着注意范围的扩大显著降低, 但在并行和序列呈现条件之间不存在显著差异; 实验2则证实实验1中对注意资源量分配的控制不会影响对项目的知觉编码效率。本研究结果表明, 分配在记忆项目上的注意资源量能够影响记忆巩固的效率, 但不会影响巩固容量。     

多目标追踪在各类人群评价与训练中的应用

多目标追踪范式主要用来探讨动态情景下对多个目标的视觉注意和记忆加工过程, 早期研究侧重于追踪过程中的影响因素及加工机制。近年来, 越来越多的研究应用多目标追踪范式对各类人群进行评价与训练, 包括儿童、老年人、神经发育障碍患者、驾驶员、运动员、电子游戏玩家以及一些其他职业群体。总体来看, 多目标追踪表现越好, 在复杂快速的动态情境中的专业表现越好; 反之, 多目标追踪表现差, 标志着认知功能可能发育不成熟或出现衰退。并且, 多目标追踪还可作为认知训练的手段, 改善老年人和神经发育障碍患者的认知功能, 提高各职业人群的专业表现。未来, 多目标追踪作为评价和训练的方法还有很大的发展空间, 包括加强特殊职业人群的模拟训练, 扩展目标人群, 结合立体视觉和真实场景, 结合身体活动, 探索多人合作的多目标追踪, 拓展用于进行情绪和社会功能的评价与训练等。     

前、后注意网络的关系--返回抑制和Stroop干扰效应

将IOR范式与Stroop任务相结合,试图从探讨IOR与Stroop干扰效应之间的关系来推测AAN和PAN之间的关系以及IOR与注意之间的关系。结果表明,在控制条件下出现了显著的IOR,在Stroop条件下没有出现明显的IOR;提示和非提示位置上均出现了显著的Stroop干扰效应,但提示位置上的干扰量要显著低于非提示位置。从IOR和Stroop干扰效应之间的关系可推知,PAN和AAN是两个有交互影响的注意网络,AAN对PAN有压制作用,而PAN对。AAN也有一定的影响。最后,作者对返回抑制与注意问的关系进行了深入的讨论。     

Effects of children’s hearing loss on the synchrony between parents’ object naming and children’s attention

Children’s attentional state during parent-child interactions is important for word learning. The current study examines the real-time attentional patterns of toddlers with and without hearing loss (N = 15, age range: 12–37 months) in parent-child interactions. High-density gaze data recorded from head-mounted eye-trackers were used to investigate the synchrony between parents’ naming of novel objects and children’s sustained attention on the named objects in joint play. Results show that the sheer quantities of parents’ naming and children’s sustained attention episodes were comparable in children with hearing loss and their peers with normal hearing. However, parents’ naming and children’s sustained attention episodes were less synchronized in the hearing loss group compared to children with normal hearing. Possible implications are discussed.     

The nature of control by spoken words over visual stimulus selection.

Eight retarded adolescents were trained to select one (a trained S+) of two visual stimuli in response to a spoken word (a trained word). Two different visual stimuli alternated randomly as the S-. To determine if the spoken work was merely a temporal discriminative stimulus for when to respond, or if it also specified which visual stimulus to select, the subjects were given intermittent presentations of untrained (novel) spoken words. All subjects consistently selected the trained S+ in response to the trained spoken word and selected the previous S- in response to the untrained spoken words. It was hypothesized that the subjects were responding away from the trained S+ in response to untrained spoken words, and control by untrained spoken words would not be observed when the trained S+ was not present. The two visual S- stimuli selected on trials of untrained spoken words were presented simultaneously. The untrained spoken words presented on these trials no longer controlled stimulus selections for seven subjects. The results supported the hypothesis that previous control by spoken words was due to responding away from the trained S+ in response to untrained spoken words.     

Psychosocial Treatment Strategies in the MTA Study: Rationale, Methods, and Critical Issues in Design and Implementation

The Collaborative Multimodal Treatment Study of Children with Attention Deficit Hyperactivity Disorder (ADHD), the MTA, is the first multisite, cooperative agreement treatment study of children, and the largest psychiatric/psychological treatment trial ever conducted by the National Institute of Mental Health. It examines the effectiveness of Medication vs. Psychosocial treatment vs. their combination for treatment of ADHD and compares these experimental arms to each other and to routine community care. In a parallel group design, 579 (male and female) ADHD children, aged 7–9 years, 11 months, were randomly assigned to one of the four experimental arms, and then received 14 months of prescribed treatment (or community care) with periodic reassessments. After delineating the theoretical and empirical rationales for Psychosocial treatment of ADHD, we describe the MTA's Psychosocial Treatment strategy applied to all children in two of the four experimental arms (Psychosocial treatment alone; Combined treatment). Psychosocial treatment consisted of three major components: a Parent Training component, a two-part School Intervention component, and a child treatment component anchored in an intensive Summer Treatment Program. Components were selected based on evidence of treatment efficacy and because they address comprehensive symptom targets, settings, comorbidities, and functional domains. We delineate key conceptual and logistical issues faced by clinical researchers in design and implementation of Psychosocial research with examples of how these issues were addressed in the MTA study.Deceased     

Do Executive Function Deficits Differentiate Between Adolescents with ADHD and Oppositional Defiant/Conduct Disorder? A Neuropsychological Study Using the Six Elements Test and Hayling Sentence Completion Test

Two neuropsychological measures of executive functions—Six Elements Tests (SET) and Hayling Sentence Completion Test (HSCT)—were administered to 110 adolescents, aged 12–15 years. Participants comprised four groups: Attention Deficit Hyperactivity Disorder (ADHD) only (n = 35), ADHD and Oppositional Defiant Disorder/Conduct Disorder (ODD/CD) (n = 38), ODD/CD only (n = 11), and a normal community control group (n = 26). Results indicated that adolescents with ADHD performed significantly worse on both the SET and HSCT than those without ADHD, whether or not they also had ODD/CD. The adolescents with ADHD and with comorbid ADHD and ODD/CD were significantly more impaired in their ability to generate strategies and to monitor their ongoing behavior compared with age-matched controls and adolescents with ODD/CD only. It is argued that among adolescents with clinically significant levels of externalizing behavior problems, executive function deficits are specific to those with ADHD. The findings support the sensitivity of these two relatively new tests of executive functions and their ecological validity in tapping into everyday situations, which are potentially problematic for individuals with ADHD.     

Testing the ability of children with attention deficit hyperactivity disorder to accurately report the effects of medication on their behavior

Children with attention deficit hyperactivity disorder (ADHD) are often treated with central nervous system stimulants, making the evaluation of medication effects an important topic for applied behavior analysts. Because assessment protocols emphasize informant reports and direct observations of child behavior, little is known about the extent to which children themselves can accurately report medication effects. Double-blind placebo-controlled procedures were used to examine whether 6 children with ADHD could recognize the effects of their medication. The children were given math worksheets to complete for 15 min during each of 14 sessions while on medication and placebo. Children completed a self-evaluation form at the end of each session, and ratings were compared to observed behavior and academic performance. Results indicated that 3 children were able to accurately report their medication status at levels greater than chance, whereas the accuracy of reports by all children was related to dosage level, differences in behavior, and the presence of adverse effects. The implications of these results for placebo-controlled research, self-monitoring of dosage levels, and accuracy training are discussed.     

Effects of methylphenidate on sensitivity to reinforcement in children diagnosed with attention deficit hyperactivity disorder: an application of the matching law

The behavior of children diagnosed with attention deficit hyperactivity disorder (ADHD) has been hypothesized to be the result of decreased sensitivity to consequences compared to typical children. The present study examined sensitivity to reinforcement in 2 boys diagnosed with ADHD using the matching law to provide more precise and quantitative measurement of this construct. This experiment also evaluated the effects of methylphenidate (MPH) on sensitivity to reinforcement of children with ADHD. Subjects completed math problems to earn tokens under four different variable-interval (VI) schedules of reinforcement presented in random order under both medicated and nonmedicated conditions. Results showed that, in the medicated condition, the matching functions for both subjects resulted in higher asymptotic values, indicating an overall elevation of behavior rate under these conditions. The variance accounted for by the matching law was also higher under the medicated conditions, suggesting that their behavior more closely tracked the changing rates of reinforcement while taking MPH compared to placebo. Under medicated conditions, the reinforcing efficacy of response-contingent tokens decreased. Results are discussed with respect to quantifying behavioral changes and the extent to which the drug interacts with prevailing contingencies (i.e., schedule values) to influence behavioral variability.