Pain perception as hierarchical Bayesian inference: A test case for the theory of constructed emotion.

An intriguing perspective about human emotion, the theory of constructed emotion considers emotions as generative models according to the Bayesian brain hypothesis. This theory brings fresh insight to existing findings, but its complexity renders it challenging to test experimentally. We argue that laboratory studies of pain could support the theory because although some may not consider pain to be a genuine emotion, the theory must at minimum be able to explain pain perception and its dysfunction in pathology.

Are multiple types of associative memory differently impacted by emotion?

The effect of emotion on associative memory is still an open question. Our aim was to test whether discrepant findings are due to differential impact of emotion on different types of associative memory or to differences in the way participants encoded stimuli across studies. We examined the effect of negative content on multiple forms of associative memory, using the same encoding task.

Test-retest reliability of Bayesian estimations of the effects of stimulation, prior information and individual traits on pain perception.

Background: There is inter-individual variability in the influence of different components (e.g. nociception and expectations) on pain perception.

Are We Any Closer to Understanding How Chronic Pain Develops? A Systematic Search and Critical Narrative Review of Existing Chronic Pain Vulnerability Models.

Identifying biopsychosocial factors underlying chronic pain vulnerability is essential for the design of preventative efforts. Multiple chronic pain vulnerability models exist, however, there is a lack of comprehensive evaluation of these models in the literature, potentially due to the lack of guidelines that specify the criteria by which these types of work should be assessed. In this work, we created evaluation criteria (based on the general goals of conceptual models), and we then used them to critically review the chronic pain vulnerability models available in the current peer-reviewed literature (identified through a systematic search).

Can neural correlates of encoding explain the context dependence of reward-enhanced memory?

Selective encoding can be studied by manipulating how valuable it is for participants to remember specific stimuli, for instance, by varying the monetary reward participants receive for recalling a particular stimulus in a subsequent memory test. It would be reasonable for participants to strategically attend more to high-reward items compared to low-reward items in mixed list contexts, but to attend both types of items equally in pure list contexts, where all items are of equal value. Reward-enhanced memory may be driven by automatic dopaminergic interactions between reward circuitry and the hippocampus and thus be insensitive to list context; or it may be driven by meta-cognitive strategies, and thus context-dependent.

Adaptive coding of pain prediction error in the anterior insula.

Background: Understanding the mechanisms behind the influence of expectation and context on pain perception is crucial for improving analgesic treatments. Prediction error (PE) signals how much a noxious stimulus deviates from expectation and is therefore crucial for our understanding of pain perception. It is thought that the brain engages in 'adaptive coding' of pain PE, such that sensitivity to unexpected outcomes is modulated by contextual information.

Reward does not modulate forgetting in free recall tests.

Reward is thought to attenuate forgetting through the automatic effect of dopamine on hippocampal memory traces. Here we report a conceptual replication of previous results where we did not observe this effect of reward. Participants encoded eight lists of pictures and recalled picture content immediately or the next day.

An EEG study on the effect of being overweight on anticipatory and consummatory reward in response to pleasant taste stimuli.

Two-thirds of adults in the United Kingdom currently suffer from overweight or obesity, making it one of the biggest contributors to health problems. Within the framework of the incentive sensitisation theory, it has been hypothesised that overweight people experience heightened reward anticipation when encountering cues that signal food, such as pictures and smells of food, but that they experience less reward from consuming food compared to normal-weight people. There is, however, little evidence for this prediction.

The Neural Representations of Emotional Experiences Are More Similar Than Those of Neutral Experiences.

Stimuli that evoke the same feelings can nevertheless look different and have different semantic meanings. Although we know much about the neural representation of emotion, the neural underpinnings of emotional similarity are unknown. One possibility is that the same brain regions represent similarity between emotional and neutral stimuli, perhaps with different strengths.

In for a penny, in for a pound: examining motivated memory through the lens of retrieved context models.

When people encounter items that they believe will help them gain reward, they later remember them better than others. A recent model of emotional memory, the emotional context maintenance and retrieval model (eCMR), predicts that these effects would be stronger when stimuli that predict high and low reward can compete with each other during both encoding and retrieval. We tested this prediction in two experiments.

Psychosocial stress has weaker than expected effects on episodic memory and related cognitive abilities: A meta-analysis.

The impact of stress on episodic memory and related cognitive abilities is well documented in both animal and human literature. However, it is unclear whether the same cognitive effects result from all forms of stress - in particular psychosocial stress. This review systematically explored the effects of psychosocial stress on episodic memory and associated cognitive abilities.

The effects of psychosocial stress on item, cued-pair and emotional memory.

Physical stress, such as from the cold-pressor test, has been robustly associated with altered memory retrieval, but it is less clear whether the same happens following psychosocial stress. Studies using psychosocial stressors report mixed effects on memory, leading to uncertainty about the common cognitive impact of both forms of stress. The current study uses a series of four carefully designed experiments, each differing by only a single critical factor to determine the effects of psychosocial stress on specific aspects of episodic memory.

The use of 'artificial saliva' as a neutral control condition in gustatory research: Artificial saliva is not a neutral gustatory stimulus.

Distilled water with NaHCO and KCl is a solution often referred to as 'artificial saliva' because its chemical composition mimics human saliva. It is often used as a control stimulus in gustatory research, especially in neuroimaging, owing to the claim that it does not produce a response in primary gustatory cortex Yet evidence that human research volunteers perceive this liquid as affectively neutral is lacking. Unpublished data from our lab suggested that this solution might be perceived as aversive.

Priming recognition memory test cues: No evidence for an attributional basis of recollection.

We argue that while the proposed memory model by Bastin et al. can explain familiarity-based memory judgements through the interaction of a core representation system and an attribution system, recollection-based memory judgements are not based on non-mnemonic signals being attributed to memory.

Quantifying how much attention rodents allocate to motivationally-salient objects with a novel object preference test.

The allocation of attention can be modulated by the emotional value of a stimulus. In order to understand the biasing influence of emotion on attention allocation further, we require an animal test of how motivational salience modulates attention. In mice, female odour triggers arousal and elicits emotional responses in males.

The Emotional Facet of Subjective and Neural Indices of Similarity.

Emotional similarity refers to the tendency to group stimuli together because they evoke the same feelings in us. The majority of research on similarity perception that has been conducted to date has focused on non-emotional stimuli. Different models have been proposed to explain how we represent semantic concepts, and judge the similarity among them.

Patterns of Neural Oscillations in Emotional Memory Discrimination.

An exciting experiment by Zheng et al. (2019) in this issue of Neuron identifies neural signatures of successful and unsuccessful emotional memory discrimination. By examining human intracranial recordings with high spatial and temporal resolution, this study provides a novel link between rodent and human research on pattern separation.

A retrieved context model of the emotional modulation of memory.

Emotion enhances episodic memory, an effect thought to be an adaptation to prioritize the memories that best serve evolutionary fitness. However, viewing this effect largely in terms of prioritizing what to encode or consolidate neglects broader rational considerations about what sorts of associations should be formed at encoding, and which should be retrieved later. Although neurobiological investigations have provided many mechanistic clues about how emotional arousal modulates item memory, these effects have not been wholly integrated with the cognitive and computational neuroscience of memory more generally.

Discussing factors associated with quality of life in cancer follow-up appointments: a preliminary test of a pragmatic model for clinical practice.

Objective:: The aim of this study is to perform a preliminary test of a practical, evidence-based model to enable discussions around quality of life-related concerns during cancer follow-up appointments.

Design:: Cross-sectional study measuring quality of life, illness perceptions, emotional distress, fatigue, and subjective cognitive complaints.

Setting:: Cancer outpatient follow-up clinics in four National Health Services in the United Kingdom.

Testing the Possibility of Model-based Pavlovian Control of Attention to Threat.

Signals for reward or punishment attract attention preferentially, a principle termed value-modulated attention capture (VMAC). The mechanisms that govern the allocation of attention can be described with a terminology that is more often applied to the control of overt behaviors, namely, the distinction between instrumental and Pavlovian control, and between model-free and model-based control. Although instrumental control of VMAC can be either model-free or model-based, it is not known whether Pavlovian control of VMAC can be model-based.

Beneficial and detrimental effects of schema incongruence on memory for contextual events.

Mental schemas provide a framework into which new information can easily be integrated. In a series of experiments, we examined how incongruence that stems from a prediction error modulates memory for multicomponent events that instantiated preexisting schemas as noted in a previous study. Each event consisted of four stimulus pairs with overlapping components, presented in four blocks (A-B, B-C, C-D, D-A).

Dissociation of immediate and delayed effects of emotional arousal on episodic memory.

Emotionally arousing events are usually better remembered than neutral ones. This phenomenon is in humans mostly studied by presenting mixed lists of neutral and emotional items. An emotional enhancement of memory is observed in these studies often already immediately after encoding and increases with longer delays and consolidation.

Local context influences memory for emotional stimuli but not electrophysiological markers of emotion-dependent attention.

Emotional enhancement of free recall can be context dependent. It is readily observed when emotional and neutral scenes are encoded and recalled together in a "mixed" list, but diminishes when these scenes are encoded separately in "pure" lists. We examined the hypothesis that this effect is due to differences in allocation of attention to neutral stimuli according to whether they are presented in mixed or pure lists, especially when encoding is intentional.

Acute memory deficits in chemotherapy-treated adults.

Data from research on amnesia and epilepsy are equivocal with regards to the dissociation, shown in animal models, between rapid and slow long-term memory consolidation. Cancer treatments have lasting disruptive effects on memory and on brain structures associated with memory, but their acute effects on synaptic consolidation are unknown. We investigated the hypothesis that cancer treatment selectively impairs slow synaptic consolidation.