Is anorexia nervosa a neuropsychological disease?

Evidence for central nervous system, and more particularly cortical, etiology of anorexia nervosa is reviewed. Topics covered are neuropsychiatric comorbidity, inheritance patterns, the neurobiology of body-image disturbance and of the eating function, perinatal and alcoholic insult to the brain, neurochemical and neuroelectric disturbance, anatomic and metabolic brain imaging, and neuropsychological impairment. It is concluded that there is indeed an important neuropsychological etiological dimension to anorexia nervosa. The profile most frequently associated with anorexia nervosa is right posterior hypometabolism, followed by right anterior hypermetabolism, both associated with right-sided abnormal electroencephalogram spiking. It is also proposed that bulimia consists of a positive neurological subtype and that restricting anorexia represents a negative neurological subtype. Priorities for further research into anorexia nervosa are specified to include twin adoption studies, brain electrical topography studies, postmortem histological studies, and experimentally inspired neuropsychological studies.     

Deprivation and satiation: The interrelations between food and wheel running

Two experiments were designed to assess whether depriving rats of food would increase the reinforcement effectiveness of wheel running (Experiment 1) and whether satiation for wheel running would decrease the reinforcement effectiveness of food (Experiment 2). In Experiment 1, a progressive-ratio schedule was used to measure the reinforcement effectiveness of wheel running when rats were deprived or not deprived of food. Completion of a fixed number of lever presses released a brake on a running wheel for 60 s, and the response requirement was systematically increased until the rat stopped pressing or until 8 hr had elapsed. The ratio value reached (and the total number of lever presses) was an inverted-U function of food deprivation (percentage body weight). In Experiment 2, when wheel running preceded test sessions, fewer food-reinforced lever presses were maintained by the progressive-ratio schedule, and responding occurred at a lower rate on a variable-interval schedule. An interpretation of these results is that deprivation or satiation with respect to one event (such as food) alters the reinforcement effectiveness of a different event (such as access to wheel running).     

IDENTIFYING THE EDUCATIVE AND SUPPRESSIVE EFFECTS OF POSITIVE PRACTICE AND RESTITUTIONAL OVERCORRECTION

Two major features of the overcorrection procedure, restitution and positive practice, were analyzed for their educative and suppressive properties in the treatment of profoundly retarded adults. Positive practice techniques that were topographically similar and dissimilar to the target behavior were studied. Eating behavior and puzzle performance were observed. Restitutional overcorrection and both forms of positive practice were effective for suppressing inappropriate behaviors. Even when appropriate behaviors had been acquired by positive practice, restitution and dissimilar positive practice were generally ineffective for increasing their rate of occurrence. However, topographically similar positive practice was successful as a means of teaching new appropriate behaviors.     

Interoceptive Awareness and Suicidal Ideation in a Clinical Eating Disorder Sample: The Role of Body Trust

Previous research has demonstrated that both suicidal ideation (SI) and eating disorders (EDs) are associated with poor interoceptive awareness (IA). Suicidality research has demonstrated that the IA dimension of lower body trust is associated with SI, suicide plans, and suicide attempts. Similarly, in ED samples, recent research supports that low body trust has been the most robust dimension of IA associated with eating pathology. However, to date, research is lacking in how dimensions of IA may be associated with SI in an ED sample, above and beyond the impact of eating pathology on SI. Thus, in a clinical ED sample, the present study sought to determine which IA dimensions predict the presence and severity of SI, above and beyond ED symptoms. Participants (N = 102) completed a clinical interview assessing SI and self-report assessments including the Multidimensional Assessment of Interoceptive Awareness (MAIA). Results demonstrated that patients with current SI reported greater ED psychopathology, lower MAIA Attention Regulation, MAIA Self-Regulation, and MAIA Trusting scores compared to patients without SI. Higher ED psychopathology and lower MAIA Attention Regulation, Self-Regulation, and Trusting subscale scores were all significantly associated with the presence of SI. However, only low MAIA Trusting scores predicted the presence of SI, above and beyond covariates (age, depression, and eating pathology). No MAIA subscales were correlated with the severity of SI. Consistent with previous research, results suggest low MAIA Trusting scores may be associated with SI in ED samples and highlight the need for future research on mechanisms of these associations.     

中国人限制性饮食和食物渴求的认知神经机制

物质丰富的时代, 如何抵御美味食物线索带来的食物渴求, 并限制饮食从而保持健康成为人们关注的重要话题之一。近年来, 国内学者为了探讨节食成功的原因, 创建中国食物图片库, 考察限制性饮食的认知神经机制, 以及成功和失败限制性饮食者的脑机制差异; 开展了特质食物渴求及中国特色的辣食渴求的认知神经研究。对推进饮食行为研究的理论发展, 也为肥胖、饮食失调等健康干预工作提供重要支持。     

视觉注意捕获的快速脱离假说与信号抑制假说

快速脱离假说和信号抑制假说都是将传统的自下而上捕获和自上而下控制结合起来的混合模式假说。快速脱离假说认为突显干扰物总能在第一时间自下而上地捕获注意, 当突显干扰物与任务要求不符时, 注意会迅速脱离该位置。信号抑制假说认为突显干扰物都会产生“注意我”的信号, 当突显干扰物与任务要求不符时, 该信号会被自上而下地抑制以阻止注意捕获发生。前者相关的研究多采用空间线索提示范式和眼动脱离范式, 实验中被试采取独子探测策略, 而后者相关的研究多采用额外单例范式的变式, 实验中被试采取特征探测策略。未来研究应采用不同的刺激类型和实验方法进一步为两个假说提供证据支持, 同时要关注奖赏、训练等因素对“捕获-脱离”和“信号-抑制”的影响。     

语素意识、快速命名对汉字听写和抄写的作用

书写是小学阶段书面语发展的重要目标之一,受到多种认知技能的影响。采用追踪研究考察了127名小学五年级儿童的语素意识和快速命名对其五、六年级时的汉字听写和抄写的影响。控制了非言语智力、语音意识后,结果发现：(1)儿童汉字听写和抄写能力随时间发展均有显著增长;(2)五年级语素意识显著预测了五、六年级两个时间点的听写,五年级快速命名仅显著预测了五年级听写;(3)五年级语素意识和快速命名预测了五年级抄写。研究表明语素意识和快速命名对汉字听写和抄写存在不同的影响作用。     

Evidence for altered configural body processing in women at risk of disorders characterized by body image disturbance

Two studies were conducted to assess appearance-related visual processing mechanisms in populations at risk of disorders characterized by body image disturbance. Using inverted stimuli, Experiment 1 assessed visual processing mechanisms associated with body, face, and house viewing in adolescents. Experiment 2 applied the same protocol to assess appearance-related configural processing in high- and low-risk adolescent women, and women recovering from disorders characterized by body image disturbance. Experiment 1 found evidence for typical configural face and body processing, although adolescent women reported higher levels of body image concern (BIC) and self-objectified to a greater extent than adolescent men. In Experiment 2, typical body inversion effects were seen in the low-risk group, whilst there was some evidence to suggest a disruption to the configural processing of body stimuli in high-risk adolescents and in women recovering from body image disorders. Women in recovery were also quicker to respond to all stimuli, whilst high-risk adolescents took longer to respond to bodies than to other stimuli. Configural face processing was intact in all groups, and effects did not directly relate to BIC or self-objectification. These findings have implications for future research looking to inform early interventions and treatment, suggesting that there could be a tendency to visually process individual body parts at the expense of the whole-body form in women at risk of developing body image disorders, as well as those in recovery.