The relationship between suppression and subsequent intrusions: the mediating role of peritraumatic dissociation and anxiety

Background and objectives: Although previous studies showed that thought and emotion suppression represent risk factors for intrusions development, the mechanisms that explain these relations were less explored. This study aims to examine the relationships between thought and emotion suppression and the symptoms of intrusion following the exposure to a trauma-related event. Moreover, we explored if these relationships would be mediated by peritraumatic state dissociation and state anxiety.

Design and methods: The trauma film paradigm was used and the participants were students (N?=?148) experimentally exposed to an aversive film to model a traumatic experience. Thought and emotion suppression were measured before the trauma exposure. After exposure, the participants completed scales for measuring state dissociation and state anxiety. Intrusive images and thoughts of the film were recorded in the subsequent week using an intrusion diary.

Results: Thought suppression predicted intrusive thoughts frequency, and this effect was mediated by the peritraumatic anxiety. State anxiety predicted both intrusive images and thoughts, while state dissociation only predicted intrusive images.

Conclusions: Intrusive images and intrusive thoughts are different phenomena and they are predicted by different variables. The practical implications of these results for posttraumatic stress disorder treatment and secondary traumatization are discussed.     

融通以达变:论钱穆先生对《易传》的诠释

钱穆先生在<易传>的研究上,先从文献入手,发表<论十翼非孔子作>以厘清孔孟旧儒与战国时代新儒的不同;其后发表<易传与小戴礼记中之宇宙论>讲述代表战国新儒思想的<易传>,虽然与孔孟旧儒不同,但仅限于天体宇宙论的建构方面,盖因此领域为道家所擅.<易传>作者吸收道家之长,融通道家宇宙论,转而建立属于儒家的宇宙论,这是值得肯定的转变.正如钱先生文中一再致意的:<易传>虽吸收道家宇宙论的思想,但并未背弃儒家人生论的精髓,所以在吸收过程中皆予以转化,换句话说,便是将老庄自然宇宙观变成儒家德性的宇宙观,以求合于传统儒家的人生哲学.     

Endogenous opioid peptides contribute to associative LTP in the hippocampal CA3 region

The medial and lateral perforant path projections to the hippocampal CA3 region display distinct mechanisms of long-term potentiation (LTP) induction, N-methyl-d-aspartate (NMDA) and opioid receptor dependent, respectively. However, medial and lateral perforant path projections to the CA3 region display associative LTP with coactivation, suggesting that while they differ in receptors involved in LTP induction they may share common downstream mechanisms of LTP induction. Here we address this interaction of LTP induction mechanisms by evaluating the contribution of opioid receptors to the induction of associative LTP among the medial and lateral perforant path projections to the CA3 region in vivo. Local application of the opioid receptor antagonists naloxone or Cys2-Tyr3-Orn5-Pen7-amide (CTOP) normally block induction of lateral perforant path-CA3 LTP. However, these opioid receptor antagonists failed to block associative LTP in lateral perforant path-CA3 synapses when it was induced by strong coactivation of the medial perforant pathway which displays NMDAR-dependent LTP. Thus strong activation of non-opioidergic afferents can substitute for the opioid receptor activation required for lateral perforant path LTP induction. Conversely, medial perforant path-CA3 associative LTP was blocked by opioid receptor antagonists when induced by strong coactivation of the opioidergic lateral perforant path. These data indicate endogenous opioid peptides contribute to associative LTP at coactive synapses when induced by strong coactivation of an opioidergic afferent system. These data further suggest that associative LTP induction is regulated by the receptor mechanisms of the strongly stimulated pathway. Thus, while medial and lateral perforant path synapses differ in their mechanisms of LTP induction, associative LTP at these synapses share common downstream mechanisms of induction.     

A new tool for assessing context conditioning induced by US-unpredictability in humans: The Martians task restyled

Unpredictability of an unconditioned stimulus (US) typically produces context conditioning in animals and humans. We modified the Martians task - a computer game measuring learning of Pavlovian associations through conditioned suppression - for assessing context conditioning in humans. One between-subjects and one within-subjects study are reported. Both experiments comprised four conditions: a predictable (Paired) condition in which the conditioned stimulus (CS) signaled the US, a neutral condition (No-US), one unpredictable condition in which the CS did not signal the US (Unpaired) and another one in which only unsignaled, temporally unpredictable USs were presented (US-only). Results showed more contextual conditioned suppression in the unpredictable conditions compared to the predictable condition. In contrast, more cued conditioned suppression occurred in the Paired condition than in the Unpaired condition. Consistent with animal research, context conditioning was increased by unpredictability. These data support the Martians task as a promising tool to extend research on human context conditioning.     

The contribution of category‐based and contextual suppression towards retrieval‐induced forgetting1

Abstract: This study examines whether both context‐related and category‐related memory impairment can be found using a retrieval‐induced forgetting procedure. One group of participants was tested using a standard retrieval‐practice paradigm, whereas for the no‐practice group the retrieval practice was replaced by irrelevant filler activity. The results showed that the within‐participant baseline items were recalled more poorly by the practice group than by the no‐practice group, whereas the practice group showed the standard retrieval‐induced forgetting effect. Thus, retrieval practice impaired recall for both within‐category and baseline items, although it impaired the former to a greater extent. This finding suggests that it is necessary to consider not only categorical relationships between items, but also context information shared by items when exploring retrieval‐induced forgetting.     

Perceptual size discrimination requires awareness and late visual areas: A continuous flash suppression and interocular transfer study

We applied continuous flash suppression (CFS) during an interocular transfer paradigm to evaluate the importance of awareness and the contribution of early versus late visual structures in size recognition. Specifically, we tested if size judgements of a visible target could be influenced by a congruent or incongruent prime presented to the same or different eye. Without CFS, participants categorised a target as “small” or “large” more quickly when it was preceded by a congruent prime – regardless of whether the prime and target were presented to the same or different eye. Interocular transfer enabled us to infer that the observed priming was mediated by late visual areas. In contrast, there was no priming under CFS, which underscores the importance of awareness. We conclude that awareness and late visual structures are important for size perception and that any subconscious processing of the stimulus has minimal effect on size recognition.     

Suppression in object-based attention

This study examines suppression in object-based attention in three experiments using an object-based attention task similar to Egly, R., Driver, J., & Rafal, R. D. (1994. Shifting visual attention between objects and locations: Evidence from normal and parietal lesion subjects. Journal of Experimental Psychology: General, 123(2), 161–177. doi:10.1037/0096-3445.123.2.161) with the addition of a distractor. In Experiment 1 participants identified a target object at one of four ends of two rectangles. The target location was validly cued on 72% of trials. The remaining 28% were located on the same or a different object. Sixty-eight percent of trials also included a distractor on one of the two objects. Experiment 1 failed to show suppression when a distractor was present, but did demonstrate the spread of attention across the attended object when no distractor was present. Experiment 2 added a mask to the paradigm to make the task more difficult and engage suppression. When suppression was engaged in the task, data showed suppression on the unattended (different) object, but not on the attended (same) object. Experiment 3 replicated findings from Experiment 1 and 2 using a within participants design. Findings are discussed in relation to the role of suppression in visual selective attention.     

Suppression history of distractor location biases attentional and oculomotor control

Past selection experience greatly affects the deployment of attention such that targets are more readily selected if their features or locations were more frequently selected in the past. Crucially, recent studies have shown similar experience-dependent effects also for salient task irrelevant stimuli: distractors exerted less interference if they appeared at a location where they were presented more often, relatively to other possible locations. Here we investigated the effects of such suppression history on the immediate behavioural correlates of attentional deployment, i.e., eye movements. Participants were to make saccadic eye movements to a target stimulus, while ignoring a highly distracting irrelevant visual onset appearing abruptly on the screen in a proportion of trials. Crucially, this irrelevant onset occurred more frequently in two locations on the visual display and our results showed that, relatively to distractors elsewhere, onsets presented at these locations became easier to ignore, giving rise to reduced oculomotor capture. Consistent with the notion that experience can alter attentional deployment towards spatial locations, these findings indicate that, through learning, the priority of high frequency locations becomes suppressed, attenuating the intrinsic saliency of distractors appearing therein. Traces left by individual events of attentional suppression decrease the processing priority of coordinates within topographic maps of the visual space.     

Parenting practices and adolescent social anxiety: A direct or indirect relationship?

Background/ObjectivesAccording to existing evidence, parental educational practices and social anxiety are to some degree connected. However, the possibility that this relationship is an indirect one and is mediated by individual factors such as self-esteem or emotional regulation has not yet been explored. The aim of this study was therefore to explore the relationship between maternal and paternal educational practices and social anxiety, and test both the direct and the indirect pathways. Method: The representative sample consisted of 2,060 Andalusian students (47.7% girls, M_age = 14.34) who filled in various self-reports. Results: The structural equation models confirmed that a direct relationship, with a low effect size, exists between parental educational practices and social anxiety and that there is also an indirect relationship, mediated by negative self-esteem and emotional suppression (the emotional regulation strategy), which accounted here for 49.1% of the variance in social anxiety. Conclusions: Parental education practices seem to act as a family asset which either promotes or hinders the development of basic attitudes and competencies such as self-esteem or emotional regulation and, by doing this, either encourages or prevents the emergence of problems such as social anxiety.