Voluntary explicit versus involuntary conceptual memory are associated with dissociable fMRI responses in hippocampus, amygdala, and parietal cortex for emotional and neutral word pairs.

Although functional neuroimaging studies have supported the distinction between explicit and implicit forms of memory, few have matched explicit and implicit tests closely, and most of these tested perceptual rather than conceptual implicit memory. We compared event-related fMRI responses during an intentional test, in which a group of participants used a cue word to recall its associate from a prior study phase, with those in an incidental test, in which a different group of participants used the same cue to produce the first associate that came to mind. Both semantic relative to phonemic processing at study, and emotional relative to neutral word pairs, increased target completions in the intentional test, but not in the incidental test, suggesting that behavioral performance in the incidental test was not contaminated by voluntary explicit retrieval. We isolated the neural correlates of successful retrieval by contrasting fMRI responses to studied versus unstudied cues for which the equivalent "target" associate was produced. By comparing the difference in this repetition-related contrast across the intentional and incidental tests, we could identify the correlates of voluntary explicit retrieval. This contrast revealed increased bilateral hippocampal responses in the intentional test, but decreased hippocampal responses in the incidental test. A similar pattern in the bilateral amygdale was further modulated by the emotionality of the word pairs, although surprisingly only in the incidental test. Parietal regions, however, showed increased repetition-related responses in both tests. These results suggest that the neural correlates of successful voluntary explicit memory differ in directionality, even if not in location, from the neural correlates of successful involuntary implicit (or explicit) memory, even when the incidental test taps conceptual processes.

Exploring the basis and boundary conditions of SenseCam-facilitated recollection.

SenseCam review has been shown to promote and sustain subsequent access to memories that might otherwise remain inaccessible. While SenseCam review facilitates recollection for personally experienced events, we know little about the boundary conditions under which this operates and about how underlying processing mechanisms can be optimally recruited to offset memory impairments of the sort that occur in dementia. This paper considers some of these issues with a view to targeting future research that not only clarifies our evolving body of theory about how memory works, but also informs about how memory-assistive technologies for patients might be employed to maximal effect. We begin by outlining key factors that are known to influence recollection. We then examine variability in the decline of memory function both in normal ageing and in dementia. Attention is drawn to similarities in the recollection deficits associated with depression and dementia, and we suggest that this may reflect shared underlying mechanisms. We conclude by discussing how one particular theoretical rationale can be intersected with key SenseCam capabilities to define priorities for ongoing and future SenseCam research.

SenseCam, imagery and bias in memory for wellbeing.

Identifying and modifying the negative interpretation bias that characterises depression is central to successful treatment. While accumulating evidence indicates that mental imagery is particularly effective in the modification of emotional bias, this research typically incorporates static and unrelated ambiguous stimuli. SenseCam technology, and the resulting video-like footage, offers an opportunity to produce training stimuli that are dynamic and self-relevant. Here participants experienced several ambiguous tasks and subsequently viewed SenseCam footage of the same tasks, paired with negative or positive captions. Participants were trained to use mental imagery to inter-relate SenseCam footage and captions. Participants reported increased levels of happy mood, reduced levels of sad mood, and increased task enjoyment following SenseCam review with positive versus negative captions. This shift in emotional bias was also evident at 24-hour follow-up, as participants recollected greater task enjoyment for those tasks previously paired with positive captions. Mental imagery appears to play an important role in this process. These preliminary results indicate that in healthy volunteers, SenseCam can be used within a bias modification paradigm to shift mood and memory for wellbeing associated with performing everyday activities. Further refinements are necessary before similar methods can be applied to individuals suffering from subclinical and clinical depression.

Exocentric coding of the mapping between valence and regions of space: Implications for embodied cognition.

Converging evidence has established that positive concepts presented on a computer screen are associated with upper regions of space, and negative concepts with a lower region of space. One explanation for this is that understanding positive or negative concepts requires the re-experiencing of direction, whereby "happy is up" and "sad is down." However, it is unclear how the regions of space are encoded in these paradigms, space can be encoded in relation to oneself (egocentrically) or in object centred coordinates that are independent of oneself (exocentrically). The current study compares exocentric and egocentric coding of space, using a variation of the Meier and Robinson (2004) paradigm. Participants were asked to evaluate valenced concepts in either the upper or lower half of the screen. Spatial primes were used such that the concepts were preceded by either an upwards or a downwards eye movement. Exocentric coding of space in this paradigm was the computer screen, whilst egocentric coding was the eye movement used to access the top or bottom of the screen. It was proposed that egocentric coding of space, being coded in the body, provides evidence of a stronger relationship between the original bodily state of 'up' or 'down' and subsequent simulation. However, significant results supported an exocentric coding of space, with faster responses to positive concepts in the upper half of the screen, and to negative concepts in the lower half, irrespective of the direction of the eye movement preceding it. The implications of this for embodied cognition are discussed.

Paying attention to social meaning: an FMRI study.

Animations of simple geometric shapes are readily interpreted as animate agents engaged in meaningful social interactions. Such animations have been shown to activate brain regions implicated in the detection of animate motion, in understanding the intentions of others as well as areas commonly linked to the processing of social and emotional information. However, attribution of animacy does not occur under all circumstances and the precise conditions under which specific regions are activated remains unclear. In a functional magnetic resonance imaging study we manipulated viewers' perspective to assess the part played by selective attention. Participants were cued to attend either to spatial properties of the movements or to the kind of social behavior it could represent. Activations that occurred to the initial cue, while observing the animations themselves and while responding to a postpresentation probe, were analyzed separately. Results showed that activity in the social brain network was strongly influenced by selective attention, and that remarkably similar activations were seen during film viewing and in response to probe questions. Our use of stimuli supporting rich and diverse social narratives likely enhanced the influence of top-down processes on neural activity in the social brain.

Reduced autobiographical memory specificity and posttraumatic stress: exploring the contributions of impaired executive control and affect regulation.

Reduced specificity of autobiographical memories retrieved to word cues on the Autobiographical Memory Test (AMT) is associated with increased posttraumatic stress in traumatized samples. Theoretical debates concerning the dominant influences on this effect have focused on affect regulation, whereby specific personal information is avoided more by those experiencing greater distress, versus compromised executive control, whereby increased distress is associated with an inability to set aside inappropriately general responses on the AMT. The present study compared these 2 views in a correlational design using a reversed version of the AMT (the AMT-R) for which trauma-exposed participants (N=36) had to generate general memories from the past and avoid specific memories. An emphasis on the role of affect regulation would predict that distress would be associated with reduced specificity (as in the standard AMT), whereas emphasis on the role of executive control would predict that this relationship would be reversed. The data supported the affect regulation account, with greater posttraumatic stress being associated with reduced memory specificity.

Understanding culture across species.

Recent claims of culture in great apes have provoked fervent argument about the 'true' definition of culture, most of which has been unhelpful. Instead, a range of definitions should be used to explore different aspects of the cognitive processes that together result in human culture, many of which can be productively studied in non-humans. A richer cognitive account of the contents of culture needs to be developed and used to compare animal and human cultures, instead of sterile searching for a cognitive Rubicon between them. Exploring six views of culture, this article highlights the fundamental contrast of whether culture evolves as a by-product of cumulative change in cognitive mechanisms, or whether it is actively selected for its advantages.

Bridging between basic theory and clinical practice.

This paper articulates and discusses the parts played by different processes and representations in the overall conduct of applied clinical science. It distinguishes two sorts of representation, theories in the science base and bridging representations needed to map from real world behaviour to basic theory and from theory back to the real world. It is then argued that macro-theories of the "normal" human mental architecture could help synthesise basic theoretical accounts of diverse psychopathologies, without recourse to special purpose clinical cognitive theories of particular psychopathologies or even specific symptoms. Using the Interacting Cognitive Subsystems model [Affect, Cognition and Change: Re-modelling Depressive Thought, Lawrence Erlbaum Associates, Hove, 1993], some specific macro-theoretic variables are identified. Concrete illustrations are given of how the essence of quite complex basic theory can be translated into a simpler representational format to help clinicians conceptualise a psychopathological state and pinpoint relevant variables that might be changed by therapeutic interventions. Some suggestions are also offered about how the inevitable problem of complexity in multiple component theories might be directly confronted.

Emotional complexity and the neural representation of emotion in motion.

According to theories of emotional complexity, individuals low in emotional complexity encode and represent emotions in visceral or action-oriented terms, whereas individuals high in emotional complexity encode and represent emotions in a differentiated way, using multiple emotion concepts. During functional magnetic resonance imaging, participants viewed valenced animated scenarios of simple ball-like figures attending either to social or spatial aspects of the interactions. Participant's emotional complexity was assessed using the Levels of Emotional Awareness Scale. We found a distributed set of brain regions previously implicated in processing emotion from facial, vocal and bodily cues, in processing social intentions, and in emotional response, were sensitive to emotion conveyed by motion alone. Attention to social meaning amplified the influence of emotion in a subset of these regions. Critically, increased emotional complexity correlated with enhanced processing in a left temporal polar region implicated in detailed semantic knowledge; with a diminished effect of social attention; and with increased differentiation of brain activity between films of differing valence. Decreased emotional complexity was associated with increased activity in regions of pre-motor cortex. Thus, neural coding of emotion in semantic vs action systems varies as a function of emotional complexity, helping reconcile puzzling inconsistencies in neuropsychological investigations of emotion recognition.

Disgust enhances the recollection of negative emotional images.

Memory is typically better for emotional relative to neutral images, an effect generally considered to be mediated by arousal. However, this explanation cannot explain the full pattern of findings in the literature. Two experiments are reported that investigate the differential effects of categorical affective states upon emotional memory and the contributions of stimulus dimensions other than pleasantness and arousal to any memory advantage. In Experiment 1, disgusting images were better remembered than equally unpleasant frightening ones, despite the disgusting images being less arousing. In Experiment 2, regression analyses identified affective impact--a factor shown previously to influence the allocation of visual attention and amygdala response to negative emotional images--as the strongest predictor of remembering. These findings raise significant issues that the arousal account of emotional memory cannot readily address. The term impact refers to an undifferentiated emotional response to a stimulus, without requiring detailed consideration of specific dimensions of image content. We argue that ratings of impact relate to how the self is affected. The present data call for further consideration of the theoretical specifications of the mechanisms that lead to enhanced memory for emotional stimuli and their neural substrates.

The memory enhancement effect of emotion is absent in conceptual implicit memory.

Memory for emotional stimuli is superior to memory for neutral stimuli. This study investigated whether this memory advantage is present in implicit memory. Memory was tested with a test of explicit memory (associate cued recall) and a test of conceptual implicit memory (free association) identical in all respects apart from the retrieval instructions. After studying emotional and neutral paired associates, participants saw the first member of the pair, the cue; in the test of explicit memory participants were instructed to recall the associate; in the test of implicit memory participants were instructed to generate the first word coming to mind associated to the word. Depth of study processing dissociated performance in the tests, confirming that the free-association test was not contaminated by an intentional retrieval strategy. Emotional pairs were better recalled than neutral pairs in the test of explicit memory but not in the equivalent test of implicit memory. The absence of an emotion effect in implicit memory implies that emotional material does not have a privileged global mnemonic status; intentional retrieval is necessary for observing the emotion-related memory advantage.

Recognition memory for pictorial material in subclinical depression.

Depression has been associated with impaired recollection of episodic details in tests of recognition memory that use verbal material. In two experiments, the remember/know procedure was employed to investigate the effects of dysphoric mood on recognition memory for pictorial materials that may not be subject to the same processing limitations found for verbal materials in depression. In Experiment 1, where the recognition test took place two weeks after encoding, subclinically depressed participants reported fewer know judgements which were likely to be at least partly due to a remember-to-know shift. Although pictures were accompanied by negative or neutral captions at encoding, no effect of captions on recognition memory was observed. In Experiment 2, where the recognition test occurred soon after viewing the pictures, subclinically depressed participants reported fewer remember judgements. All participants reported more remember judgements for pictures of emotionally negative content than pictures of neutral content. Together, these findings demonstrate that recognition memory for pictorial stimuli is compromised in dysphoric individuals in a way that is consistent with a recollection deficit for episodic detail and also reminiscent of that previously reported for verbal materials. These findings contribute to our developing understanding of how mood and memory interact.

Depression and attention to two kinds of meaning: A cognitive perspective.

The complexity of a mental disorder such as depression is such that a way of interlinking the neural, mental and interpersonal levels is needed. This paper proposes that a theoretical framework which distinguishes, and relates, macro-theory and micro-theory at these levels can serve this purpose. The 'Interacting Cognitive Subsystems' approach to mental architecture is used to show how, via the detailed specification of mental processes and representations, a macro-theory of mental architecture contributes to our understanding of depressed states. In the account advanced by Teasdale and Barnard depressed states are seen as being maintained by an abnormal version of a dynamic dialogue between two qualitatively distinct types of meaning: one is referentially specific, propositional meaning, the other consists of holistic schemata rich in latent content and is called implicational meaning. In depressed states with ruminative and avoidant thought patterns, the mental function of attention is seen as being directed preferentially at propositional meanings. There is a corresponding neglect of attention to implicational meanings. The paper concludes with a brief discussion of how this approach can address transdiagnostic issues and how it may suggest new strategies for therapeutic interventions.

Assessing the automaticity of moral processing: efficient coding of moral information during narrative comprehension.

A long-standing theoretical debate concerns the involvement of principled reasoning versus relatively automatic intuitive-emotional processing in moral cognition. To address this, we investigated whether the mental models formed during story comprehension contain a moral dimension and whether this process is affected by cognitive load. A total of 72 participants read stories about fictional characters in a range of moral situations, such as a husband being tempted to commit adultery. Each story concluded with a "moral" or "immoral" target sentence. Consistent with a framework of efficient extraction of moral information, participants took significantly longer to read immoral than moral target sentences. Moreover, the magnitude of this effect was not compromised by cognitive load. Our findings provide evidence of efficient coding of moral dimensions during narrative comprehension and demonstrate that this process does not require cognitively intense forms of principled reasoning.

The amygdala response to images with impact.

Effective photojournalism provokes an emotional reaction and leaves a lasting impression upon the viewer. Striking and memorable images are often said to possess 'impact'. Within cognitive neuroscience memorable emotional images evoke a greater amygdala response. Research to date has focused on arousal as a causative factor, while the contribution of appraisal dimensions relating to salience of an item, goal relevance, or impact are yet to be addressed. We explored how differences in ratings of impact influenced amygdala activity to negative emotional images matched for valence, arousal and other factors. Increased amygdala activation was found to high impact when compared to neutral images, or high impact when compared to low impact images (matched for arousal). Our findings demonstrate that the amygdala response to emotional stimuli is not a function of arousal (or valence) alone and accord more with the proposal that the amygdala responds to the significance or relevance of an event.

Reducing specificity of autobiographical memory in nonclinical participants: The role of rumination and schematic models.

Two experiments are reported in which nondysphoric participants, not prone to excessive levels of rumination in everyday life, were asked to retrieve autobiographical memories using the Williams and Broadbent ( 1986 ) procedure (AMT). In the first experiment, two variants of a self-related category fluency task were interleaved among sets of autobiographical memory cues. In one variant (blocked) a normal model of analytic rumination was induced by grouping prompts on a single superordinate theme together. In the other (intermixed) prompts from several different themes were grouped together. It was predicted that the blocked variant would reduce the number of specific memories recollected and increase the number of categoric memories relative to the intermixed variant. This prediction was confirmed and provides the first demonstration of a bidirectional causal influence of analytic rumination on the balance between specific and categoric retrievals. A second experiment showed no alteration in this balance when the same fluency manipulation involved animal-related categories rather than self-related ones. The results support a two component model of autobiographical retrieval being driven in part by the extent to which an analytic mode of processing is adopted in the short term and in part by the level of differentiation in self-related schematic models.

Recollection deficits in dysphoric mood: an effect of schematic models and executive mode?

Depression and dysphoric mood states are often accompanied by quantitative or qualitative shifts in performance across a range of retention tasks. This study focuses on the recollection of both autobiographical events and word lists in dysphoric states. Recollection occurs when people are aware of some contextual detail allied to the encoding experience. This study establishes the presence of a recollection deficit in dysphoria in two distinct paradigms. In both autobiographical recall and in recognition memory, recollection in a dysphoric group was at lower levels than recollection in matched controls. The study examines the hypothesis that the extent of recollection is influenced by two factors: (1) the degree of differentiation of schematic mental models; and (2) the executive mode that predominates when memory tasks are carried out, with the latter assumed to be altered by rumination. The relationship between responses based on recollection and alternative mnemonic responses could be predicted by measures of these two factors. The results are discussed in terms of the Interacting Cognitive Subsystems model (Teasdale & Barnard, 1993) and the perspective it offers on the relationship between meaning systems and executive functions (Barnard, 1999).