Instructed fear learning,extinction, and recall: additive effects of cognitive information on emotional learning of fear

The effects of instruction on learning of fear and safety are rarely studied. We aimed to examine the effects of cognitive information and experience on fear learning. Fourty healthy participants, randomly assigned to three groups, went through fear conditioning, extinction learning, and extinction recall with two conditioned stimuli (CS+). Information was presented about the presence or absence of conditioned stimulus–unconditioned stimulus (CS–US) contingency at different stages of the experiment. Information about the CS–US contingency prior to fear conditioning enhanced fear response and reduced extinction recall. Information about the absence of CS–US contingency promoted extinction learning and recall, while omission of this information prior to recall resulted in fear renewal. These findings indicate that contingency information can facilitate fear expression during fear learning, and can facilitate extinction learning and recall. Information seems to function as an element of the larger context in which conditioning occurs.     

Ignorance reflects preference: the influence of selective ignoring on evaluative conditioning

In the current experiment, we investigated the mechanism underlying the modulation of evaluative conditioning (EC) due to selective attention. Conditioned stimulus–unconditioned stimulus (CS–US) pairs were presented in a just recently introduced adapted Flanker paradigm [Blask, K., Walther, E., & Frings, C. (2016). When congruence breeds preference: The influence of selective attention processes on evaluative conditioning. Cognition and Emotion. doi:10.1080/02699931.2016.1197100] with CSs as targets and USs as task-irrelevant distracters. In order to disentangle stimulus congruency and response compatibility and in order to observe a possible impact of response compatibility, EC in an incongruent/incompatible condition was compared to EC in an incongruent/neutral condition. Results show that EC and contingency memorywere significantly reduced in the incongruent/incompatible condition relative to the incongruent/neutral condition. These findings support the notion that the modulation of EC due to selective attention can be based on the selective ignoring of the US at the level of response compatibility.     

条件反射性免疫抑制研究的新进展

条件反射性免疫抑制 (CIS)模式基于巴甫洛夫条件反射的机理 ,通过大脑对免疫系统进行调节 ,是一种重要的心理神经免疫学方法。近 10年来的研究取得了一些重要的进展。首先 ,条件反射性免疫抑制模型已证实是非常稳定可靠的心理神经免疫模型。其次 ,关于CIS的机制在体液、细胞、神经学方面都有广泛的研究 ,而近年来更趋向于对神经性通路的探讨。而CIS的临床应用性研究也在实验动物身上取得了稳定可靠的结果 ,证实了其未来临床应用的可行性及潜力     

Conducting extinction in multiple contexts does not necessarily attenuate the renewal of shock expectancy in a fear-conditioning procedure with humans

The renewal of Pavlovian-conditioned responses may provide a model for the relapse of fear following extinction-based treatments for anxiety disorders. Renewal can be observed if conditional stimulus (CS) and unconditional stimulus (US) pairings are given in one context, extinction trials of CS presentations in a second context, prior to test trials of CS presentations in the original acquisition context (ABA renewal). We examined ABA renewal in humans by using a fear-conditioning procedure with an unpleasant shock US. A renewal of rated shock expectancy was demonstrated with this procedure. Conducting extinction treatment in multiple contexts was expected to attenuate the renewal effect. However, the renewal of shock expectancy persisted when extinction treatment was given across three or five different contexts. With the current renewal design, learning task, and measure of conditioned behaviour, extinction treatment does not appear to readily generalise to the test context. The use of multiple extinction treatments in a clinical setting may not necessarily reduce the likelihood of relapse via a renewal effect.     

The effects of context extinction on US signal value

Two experiments with rats examined the effects of context extinction on responding to the signal value of an unconditioned stimulus (US). In Experiment 1, US signal value was first trained when a single food pellet signaled the delivery of three additional pellets. After training, rats received either context extinction (CE) or home cage (HC) exposure before testing US signal value by single food pellet presentations. Results showed responding was significantly reduced in Group CE compared to Group HC. Experiment 2 replicated Experiment 1 and showed that exposure to a different context did not reduce responding to the signal value of a US. The results complement research by Kehoe et al. [Kehoe, E. J., Weidemann, G., & Dartnall, S. (2004). Apparatus exposure produces profound declines in conditioned nictitating-membrane responses to discrete conditioned stimuli by the rabbit (Oryctolagus cuniculus). Journal of Experimental Psychology: Animal Behavior Processes, 30, 259–270.] and have key implications for prominent theories of conditioning.     

Instrumental conditioning of aggressive behavior in rats

A method has been developed for bringing an aggressive response under stimulus control. It was found that the number of conditioned aggyessive responses was maximal when low-weight target rats were used. The latencies of the conditioned responses toward target animals of 124 gm were significantly lower than those toward animals of 221 and 284 gm. The application of an extinction procedure on the conditioned aggressive response substantially increased the total number of emitted aggressive responses.     

Socially mediated learning in male Betta splendens. III: Rapid acquisitions

In four experiments with male Siamese fighting fish, the classical conditioning of visual/spatial cues with elicitors of aggression was demonstrated. These studies show that this type of socially mediated learning is more rapidly conditioned than was previously known. One 15-min training session is adequate to condition a preference for those cues that had recently been paired with conspecific images. Finally, behavior occurring during acquisition, in the presence of aggression-eliciting cues, was uncorrelated with the magnitude of the learned preferences that were assayed during extinction tests and in the absence of social stimuli.     

预期错误在恐惧记忆更新中的作用与机制

依据错误驱动的学习理论,行为预期结果与实际结果之间的不匹配即预期错误(Predictionerror,PE)是学习产生的驱动因素。作为显著性信息中的一种,预期错误和物理显著性、惊讶、新异性等存在信息加工阶段的不同,与记忆更新的关系也有差异。近年来,记忆再巩固干预范式(reconsolidation interference)被证明可用于人类条件性恐惧记忆的更新,其中记忆提取激活阶段所包含的预期错误起到了引发记忆“去稳定”、开启记忆再巩固的关键作用。在促进恐惧记忆更新的行为机制上,PE被认为是记忆去稳定的必要非充分条件。记忆提取必须包含适量的PE,但其引发的是记忆去稳定、消退还是中间状态,还需结合记忆本身性质确定。在促进恐惧记忆更新的神经机制上,杏仁核、导水管周围灰质(PAG)、海马均在PE探测和计算过程中具有重要作用;前额叶皮层(PFC)及其亚区在PE开启记忆再巩固过程中扮演了重要角色。上述过程又受到神经系统中特定神经递质的重要调节,尤其是多巴胺能和谷氨酸能。未来研究应进一步探索基于PE计算模型的量化研究,整合PE与其他边界条件的交互作用,考察不同类型显著性在记忆再巩固中的作用等;并亟...     

Affective-Evaluative Learning in Humans: A Form of Associative Learning or Only an Artifact?

The status of evaluative conditioning (EC) as a distinct form of associative learning was called in question by Field and Davey (1997, 1998, 1999), who argued that in the typical visual EC paradigm, nonassociative visual concept learning is responsible for the evaluative changes observed. Especially, the use of only within-subject control conditions instead of independent control groups was criticized. The present three experiments show (a) that EC effects can be demonstrated within another sensory modality than visual perception and (b) that EC effects are demonstrable in a between-subject design (including a successful replication attempt). A further result was that these EC effects do not require participants' conscious awareness. The data provide no support for an artifactual account of EC but suggest an interpretation of EC as a form of associative learning.     

Differential Conditioning Based on a Difference in the Predictability of Reinforcement

A Pavlovian procedure containing a set of several alternative reliable trial stimuli and a set of several alternative unreliable trial stimuli was used to determine if reliability of outcome, per se, would differentially condition additional trial stimuli that either preceded or followed those original trial stimuli in a serial conditioning paradigm. The reinforcing effectiveness of the antecedent stimuli themselves was later tested in a higher-order conditioning design. It was found that different rates could be established to the different antecedent stimuli in the absence of a difference in the probability of reinforcement. Further, stimuli paired with those antecedent stimuli in the higher-order conditioning test also exhibited a difference in rate. It was concluded that a combination of a stimulus that is always followed by food and another that is never followed by food are, in net, a more effective reinforcer than a common stimulus that has the same overall probability of reinforcement but which is followed by both outcomes.