THE “WHERE IS IT?” REFLEX: AUTOSHAPING THE ORIENTING RESPONSE

The goal of this review is to compare two divergent lines of research on signal-centered behavior: the orienting reflex (OR) and autoshaping. A review of conditioning experiments in animals and humans suggests that the novelty hypothesis of the OR is no longer tenable. Only stimuli that represent biological “relevance” elicit ORs. A stimulus may be relevant a priori (i.e., unconditioned) or as a result of conditioning. Exposure to a conditioned stimulus (CS) that predicts a positive reinforcer causes the animal to orient to it throughout conditioning. Within the CS-US interval, the initial CS-directed orienting response is followed by US-directed tendencies. Experimental evidence is shown that the development and maintenance of the conditioned OR occur in a similar fashion both in response-independent (classical) and response-dependent (instrumental) paradigms. It is proposed that the conditioned OR and the signal-directed autoshaped response are identical. Signals predicting aversive events repel the subject from the source of the CS. It is suggested that the function of the CS is not only to signal the probability of US occurrence, but also to serve as a spatial cue to guide the animal in the environment.     

Measuring anxious responses to predictable and unpredictable threat in children and adolescents

Research has highlighted the need for new methods to assess emotions in children on multiple levels to gain better insight into the complex processes of emotional development. The startle reflex is a unique translational tool that has been used to study physiological processes during fear and anxiety in rodents and in human participants. However, it has been challenging to implement developmentally appropriate startle experiments in children. This article describes a procedure that uses predictable and unpredictable aversive events to distinguish between phasic fear and sustained anxiety in children and adolescents. We investigated anxious responses, as measured with the startle reflex, in youths (N = 36, mean age = 12.63 years, range = 7-17) across three conditions: no aversive events (N), predictable aversive events (P), and unpredictable aversive events (U). Short-duration cues were presented several times in each condition. Aversive events were signaled by the cues in the P condition but were presented randomly in the U condition. Participants showed fear-potentiated startle to the threat cue in the P condition. Startle responses were also elevated between cues in the U condition compared with the N condition, suggesting that unpredictable aversive events can evoke a sustained state of anxiety in youths. This latter effect was influenced by sex, being greater in girls than in boys. These findings indicate the feasibility of this experimental induction of the startle reflex in response to predictable and unpredictable events in children and adolescents, enabling future research on interindividual differences in fear and anxiety and their development in youths.     

Inter-hemispheric remapping between arm proprioception and vision of the hand is disrupted by single pulse TMS on the left parietal cortex

Parietal cortical areas are involved in sensori-motor transformations for their respective contralateral hemifield/body. When arms of the subjects are crossed while their gaze is fixed straight ahead, vision of the hand is processed by the hemisphere ipsilateral to the arm position and proprioception of the arm by the contralateral hemisphere. It induces interhemispheric transfer and remapping. Our objective was to investigate whether a single pulse TMS applied to the left parietal cortical area would disturb interhemispheric remapping in a similar case, and would increase a simple reaction time (RT) with respect to a control single pulse TMS applied to the frontal cortical area. Two LED were superimposed and located in front of the subjects on the saggital axis. Subjects were asked to carefully fixate on these LED during each trial. The lighting of the red LED was used as a warning signal. Following the green one was illuminated after a variable delay and served as a go-signal. The hand for the response was determined before the start of each trial. TMS was applied to the left parietal, the left frontal cortical areas, or not applied to the subject. Results revealed that: (1) Irrespective of its location, single pulse TMS induced a non-specific effect similar to a startle reflex and reduced RT substantially (15 ms on average) with respect to a control condition without TMS (mean value = 153 ms). (2) Irrespective of TMS, RT were shorter when the right or the left hand was positioned in the right visual hemi-field (i.e. normal and crossed positions respectively). (3) Finally, RT increased when single pulse TMS was applied to the left parietal area and when hands were crossed irrespective of which hand was used. We concluded that interhemispheric sensori-motor remapping was disrupted by a single pulse TMS that was applied to the left parietal cortex. This effect was also combined with some visual attention directed towards the hand located on the right visual hemi-field.     

Medication for Complex Posttraumatic Disorders

Treatment guidelines and reviews of outcome studies agree that drugs are valuable for moderation of irrational moods and impulsivity that interfere with thoughtfulness and cooperativeness. As such, they empower patients to make good use of psychotherapy for mastery of the risk of betrayal in intimate relationships, which is the typical recurrent traumatic event in complex posttraumatic disorders. Psychotherapy, for its part, has demonstrated correction and lasting remission of disorder in the aftermath of certain kinds of single trauma and promises further development to achieve similar efficacy for complex posttraumatic disorders. This article summarizes the strengths and limitations of each class of psychiatric drugs. It explains how the natural course of complex posttraumatic disorders greatly contaminates observations of medication efficacy and fosters unrealistic expectations for drug development.     

Congruence or coherence? Emotional and physiological responses to colours in synaesthesia

Lexical–chromatic synaesthesia is a condition in which letters and/or words elicit percepts of synaesthetic colours, termed photisms. Anecdotal data suggest that synaesthetes are particularly sensitive to inconsistencies between their synaesthetic percepts and the real world, e.g., it can be annoying and unpleasant for them to see a letter printed in a colour different than the respective photism colour. For R, a synaesthete subject who participated in the present study, the photisms possess specific emotional values (a red photism is pleasing and attractive, green is repulsive and unpleasant, etc.). In contrast to the anecdotal data, R does not always find the colour–photism incongruence to be disturbing. More importantly, he states that it is the emotional coherence between the stimulus and the corresponding photism that matters. In a series of experiments, we studied this new concept of emotional coherence on three levels—subjective (self-report), behavioural, and physiological, corroborating R's introspective statements. Besides the implications of the concept of coherence itself, the results presented here suggest that even highly subjective cognitive constructs can be approached and measured experimentally, uncovering the workings of the underlying psychophysiological mechanisms.     

The Moro reaction: More than a reflex,a ritualized behavior of nonverbal communication

ObjectiveTo propose a phylogenetic significance to the Moro reflex which remains unexplained since its publication in 1918 because both hands are free at the end of the gesture.MethodAmong the 75 videos of healthy term newborns we have filmed in a research project on antenatal education to parenthood, we describe a sequence that clearly showed the successive movements of the Moro reflex and we report the occurrence of this reflex in the videos that were recorded from Time 0 of birth defined as the moment that lies between the birth of the thorax and the pelvis of the infant.ResultsThe selected sequence showed the following succession of the newborn’s actions: quick extension-adduction of both arms, the orientation of the body, head and eyes towards a human person, and full extension-abduction of both arms with spreading of the fingers, crying and a distressed face. There were 13 Moro reflexes between 2 and 14 s from Time 0 of birth. We found a significant association between the occurrence of the Moro reflex and the placement of the newborn at birth in supine position on the mother’s abdomen (p = 0.002).DiscussionThe quick extension-adduction of both arms which started the sequence may be considered as a startle reflex controlled by the neural fear system and the arm extension-adduction which followed as a Moro reflex. The characteristics of all Moro reflexes were those of ritualization: amplitude, duration, stereotype of the gestures. This evolutionary process turns a physiological behavior, grasping in this case, to a non-verbal communicative behavior whose meaning is a request to be picked up in the arms. The gestures associated with the Moro reflex: crying and orientation of the body, head, and eyes towards a human person, are gestures of intention to communicate which support our hypothesis. The neural mechanism of the Moro reaction probably involves both the fear and the separation-distress systems.ConclusionThis paper proposes for the first time a phylogenetic significance to the Moro reflex: a ritualized behavior of nonverbal communication. Professionals should avoid stimulating the newborns’ fear system by unnecessarily triggering Moro reflexes. Antenatal education should teach parents to respond to the Moro reflexes of their newborn infant by picking her up in their arms with mother talk.     

Global VOR gain adaptation during near fixation to foveal targets

Long-term rotational vestibulo-ocular (VOR) adaptation occurs during systematic dysmetria between visual and vestibular afferents, adjusting eye-rotation angular velocity to re-establish retinal stability of the visual field. Due to translational motion of the eyes during head rotation, VOR gain is higher when fixating near objects. The current study measures VOR in humans before and after 6 min of exposure to a foveal near-target during sinusoidal whole-body rotation at 0.45 Hz. All of six participants showed post-exposure increases in open-loop VOR gain after fixating near targets, demonstrating a mean modulation increase of open-loop VOR gain from 0.86 before adaptation to 1.2 after adaptation. We discuss a number of theoretical and applied implications.     

The relevance of castration and circumcision to the origins of psychoanalysis: 1. The medical context1

In this paper the author outlines and discusses the origins and the decline of castration and circumcision as a cure for the nervous and psychic disturbances in women and little girls between 1875 and 1905. The author argues that the opposition to this medical practice affected the conception of hysteria, promoting a distinction between sexuality and the genital organs, and the emergence of an enlarged notion of sexuality, during the period from Freud’s medical education to the publication of the Three Essays on the Theory of Sexuality. The hypothesis is put forward that Freud came directly in contact with the genital theory of the neurosis at the time of his training on the nervous disturbances in children with the paediatrician, Adolf Baginsky, in Berlin, in March 1886. It is hypothesized that this experience provoked in Freud an abhorrence of circumcision ‘as a cure or punishment for masturbation’, prompting an inner confrontation which resulted in a radical reorganization of the way of thinking about sexuality. It is also suggested that this contributed to Freud developing a capacity to stay with contradictions, something which would become a central quality of the psychoanalytic attitude.     

惊跳反射的生理心理机制

惊跳反射作为动物及人类在应对意外刺激或遇到险情时的一种避险保护反应,具有重要的生物学意义。以往的研究较多关注听觉惊跳反射,在反应指标上多采用眼部及面部表情肌的反应,如眨眼反射。惊跳反射的生理机制为突发性强刺激直接传向杏仁核的直接通路所致。惊跳反射增强的心理机制可能为致敏作用或恐惧性条件作用,而惊跳反射衰减的心理机制可能是适应、前脉冲抑制或愉快衰减。未来的研究应关注视觉惊跳反射,观察全身躯体姿势维持肌肉群的反应模式,并以先进设备对惊跳反射的信息加工脑机制进行深入的研究     

家兔具有分辨红绿的色觉行为

本文在11只上海家免上进行了色觉行为学的实验研究。通过限制方位、光强等可能成为条件刺激的因素,并排除了声音、气味、背景光刺激等的干扰,确保颜色成为唯一的条件刺激,建立食物性红绿色觉分辨条件反射。经过适应、筛选、驯练和测试,在家兔上建立了对绿光稳固的条件反射。该结果显示兔具有颜色分辨能力。