Watching my mind unfold versus yours: an fMRI study using a novel camera technology to examine neural differences in self-projection of self versus other perspectives

Improving autobiographical memory in schizophrenia using wearable cameras: A single-case experimental study

Autobiographical memory (AM) impairments influence both sense of identity and social functioning of patients with schizophrenia. However, cognitive remediation methods addressing these difficulties do not sufficiently consider the heterogeneity of this disorder and frequently face methodological limitations. The aim of the present study was to evaluate the efficacy of a method using a wearable camera (NarrativeClip®), through an alternating treatments design across two types of AM training. In parallel, repeated measures were used to appreciate the efficacy, specificity, and generalizability of the programme's benefits. Three patients were invited to wear the camera during 24 personal events. Ten of these events memories were trained by visual cueing (wearable camera condition), 10 others by verbal cueing (written diary condition) and 4 were not trained (control condition). Using pictures collected by the wearable camera seemed particularly relevant, since it promoted more detailed recalls than the diary method, from the first training session and until the end of a one-year follow-up. In addition, the repeated measures performed revealed (1) the efficacy (improvement in AM capacities after participating in the programme), (2) specificity (persistence of working memory deficits), and (3) generalizability (improvement in measures of episodic memory) of our cognitive remediation programme's effects.

Lifelogging as a rehabilitation tool in patients with amnesia: A narrative literature review on the effect of lifelogging on memory loss

Visual lifelogging is the procedure that enables individuals to visually record daily life activities by means of small wearable cameras, which can be worn around the neck or on the clothing. Lifelogging devices automatically take pictures or videos after pre-set time intervals or after dynamic input changes. Although some studies have shown effectivity of reviewing lifelogging images in brain-damaged individuals with forms of amnesia as a rehabilitation tool, systematic endeavours to overview this literature is yet missing. The aim of this narrative literature review was to review all the available case-studies, experimental studies and group studies in brain-damaged individuals applying lifelogging devices in a clinical context. The included studies showed efficacy for both subjective and objective measures of memory. In mild to severe amnesia, reviewing images recorded by the lifelogging device was beneficial to subjective and objective measures of memory. Lifelogging is demonstrated to have a great potential in helping people who are suffering from memory loss. It can offer an excellent alternative to currently more frequently used memory rehabilitation techniques and can be applied more in clinical settings.

Hunters and Gatherers of Pictures: Why Photography Has Become a Human Universal

Photography is ubiquitous worldwide. We analyzed why people take, share, and use personal photographs, independent of their specific cultural background. These behaviors are still poorly understood. Experimental research on them is scarce. Smartphone technology and social media have pushed the success of photography, but cannot explain it, as not all smartphone features are widely used just because they are available. We analyzed properties of human nature that have made taking and using photographs functional behaviors. We did this based on the four levels, which Nikolaas Tinbergen suggested for analyzing why animals behave in a particular way. Including findings from multiple disciplines, we developed a novel conceptual framework-the "Mental Utilization Hypothesis of Photography." It suggests that people adopt photography because it matches with core human mental mechanisms mainly from the social domain, and people use photography as a cognitive, primarily social coping strategy. Our framework comprises a range of testable predictions, provides a new theoretical basis for future empirical investigations into photography, and has practical implications. We conclude that photography has become a human universal, which is based on context-sensitive mental predispositions and differentiates itself in the social and societal environment.

The lateral intraparietal sulcus takes viewpoint changes into account during memory-guided attention in natural scenes

Previous studies demonstrated that long-term memory related to object-position in natural scenes guides visuo-spatial attention during subsequent search. Memory-guided attention has been associated with the activation of memory regions (the medial-temporal cortex) and with the fronto-parietal attention network. Notably, these circuits represent external locations with different frames of reference: egocentric (i.e., eyes/head-centered) in the dorsal attention network vs. allocentric (i.e., world/scene-centered) in the medial temporal cortex. Here we used behavioral measures and fMRI to assess the contribution of egocentric and allocentric spatial information during memory-guided attention. At encoding, participants were presented with real-world scenes and asked to search for and memorize the location of a high-contrast target superimposed in half of the scenes. At retrieval, participants viewed again the same scenes, now all including a low-contrast target. In scenes that included the target at encoding, the target was presented at the same scene-location. Critically, scenes were now shown either from the same or different viewpoint compared with encoding. This resulted in a memory-by-view design (target seen/unseen x same/different view), which allowed us teasing apart the role of allocentric vs. egocentric signals during memory-guided attention. Retrieval-related results showed greater search-accuracy for seen than unseen targets, both in the same and different views, indicating that memory contributes to visual search notwithstanding perspective changes. This view-change independent effect was associated with the activation of the left lateral intra-parietal sulcus. Our results demonstrate that this parietal region mediates memory-guided attention by taking into account allocentric/scene-centered information about the objects' position in the external world.

Differentiating Real-World Autobiographical Experiences without Recourse to Behaviour

Investigating human consciousness based on brain activity alone is a key challenge in cognitive neuroscience. One of its central facets, the ability to form autobiographical memories, has been investigated through several fMRI studies that have revealed a pattern of activity across a network of frontal, parietal, and medial temporal lobe regions when participants view personal photographs, as opposed to when they view photographs from someone else's life. Here, our goal was to attempt to decode when participants were re-experiencing an entire event, captured on video from a first-person perspective, relative to a very similar event experienced by someone else. Participants were asked to sit passively in a wheelchair while a researcher pushed them around a local mall. A small wearable camera was mounted on each participant, in order to capture autobiographical videos of the visit from a first-person perspective. One week later, participants were scanned while they passively viewed different categories of videos; some were autobiographical, while others were not. A machine-learning model was able to successfully classify the video categories above chance, both within and across participants, suggesting that there is a shared mechanism differentiating autobiographical experiences from non-autobiographical ones. Moreover, the classifier brain maps revealed that the fronto-parietal network, mid-temporal regions and extrastriate cortex were critical for differentiating between autobiographical and non-autobiographical memories. We argue that this novel paradigm captures the true nature of autobiographical memories, and is well suited to patients (e.g., with brain injuries) who may be unable to respond reliably to traditional experimental stimuli.

A behavioural and ERP investigation of the wearable camera photo review in autobiographical memory

Wearable camera photo review has successfully been used to enhance memory, yet very little is known about the underlying mechanisms. Here, the sequential presentation of wearable camera photos - a key feature of wearable camera photo review - is examined using behavioural and EEG measures. Twelve female participants were taken on a walking tour, stopping at a series of predefined targets, while wearing a camera that captured photographs automatically. A sequence of four photos leading to these targets was selected (∼ 200 trials) and together with control photos, these were used in a recognition task one week later. Participants' recognition performance improved with the sequence of photos (measured in hit rates, correct rejections, & sensitivity), revealing for the first time, a positive effect of sequence of photos in wearable camera photo review. This has important implications for understanding the sequential and cumulative effects of cues on episodic remembering. An old-new ERP effect was also observed over visual regions for hits vs. correct rejections, highlighting the importance of visual processing not only for perception but also for the location of activated memory representations.

Brain networks involved in place recognition based on personal and spatial semantics

Have you ever been to Krakow? If so, then you may recognize the Wawel Royal Castle from a picture due to your personal semantic memory, which stores all autobiographically significant concepts and repeated events of your past. If not, then you might still recognize the Wawel Royal Castle and be able to locate it on a map due to your spatial semantic memory. When recognizing a familiar landmark, how does neural activity depend on your memory related to that place? To address this question, we combined a novel task - the Krakow paradigm - with fMRI. In this task, participants are presented with a set of pictures showing various Krakow landmarks, each followed by two questions - one about its location, and the other about seeing the place in real-life, to trigger spatial and/or personal semantic memory, respectively. Group independent component analysis of fMRI data revealed several brain networks sensitive to the task conditions. Most sensitive was the medial temporal lobe network comprising bilateral hippocampus, parahippocampal, retrosplenial, and angular gyri, as well as distinct frontal areas. In agreement with the contextual continuum perspective, this network exhibited robust stimulus-related activity when the two memory types were combined, medium for spatial memory, and the weakest for baseline condition. The medial prefrontal network showed the same, pronounced deactivation for spatial memory and baseline conditions, yet far less deactivation for places seen in real-life. This effect was interpreted as self-referential processes counterbalancing the suppression of the brain's 'default mode.' In contrast, the motor, frontoparietal, and cingulo-opercular networks exhibited the strongest response-related activity for the spatial condition. These findings indicate that recognizing places based solely on general semantic knowledge requires more evidence accumulation, additional verbal semantics, and greater top-down control. Thus, the study imparts a novel insight into the neural mechanisms of place recognition. The Krakow paradigm has the potential to become a useful tool in future longitudinal or clinical studies.

Reminders activate the prefrontal-medial temporal cortex and attenuate forgetting of event memory

Replicas of an aspect of an experienced event can serve as effective reminders, yet little is known about the neural basis of such reminding effects. Here we examined the neural activity underlying the memory-enhancing effect of reminders 1 week after encoding of naturalistic film clip events. We used fMRI to determine differences in network activity associated with recently reactivated memories relative to comparably aged, non-reactivated memories. Reminders were effective in facilitating overall retrieval of memory for film clips, in an all-or-none fashion. Prefrontal cortex and hippocampus were activated during both reminders and retrieval. Peak activation in ventro-lateral prefrontal cortex (vPFC) preceded peak activation in the right hippocampus during the reminders. For film clips that were successfully retrieved after 7 days, pre-retrieval reminders did not enhance the quality of the retrieved memory or the number of details retrieved, nor did they more strongly engage regions of the recollection network than did successful retrieval of a non-reminded film clip. These results suggest that reminders prior to retrieval are an effective means of boosting retrieval of otherwise inaccessible episodic events, and that the inability to recall certain events after a delay of a week largely reflects a retrieval deficit, rather than a storage deficit for this information. The results extend other evidence that vPFC drives activation of the hippocampus to facilitate memory retrieval and scene construction, and show that this facilitation also occurs when reminder cues precede successful retrieval attempts. The time course of vPFC-hippocampal activity during the reminder suggests that reminders may first engage schematic information meditated by vPFC followed by a recollection process mediated by the hippocampus.

Deconstructing the Posterior Medial Episodic Network

Our ability to remember or imagine specific events involves the construction of complex mental representations, a process that engages cortical and hippocampal regions in a core posterior medial (PM) brain network. Existing theoretical approaches have described the overarching contributions of the PM network, but less is known about how episodic content is represented and transformed throughout this system. Here, we review evidence of key functional interactions among PM regions and their relation to the core cognitive operations and representations supporting episodic construction. Recent demonstrations of intranetwork functional diversity are integrated with existing accounts to inform a network-based model of episodic construction, in which PM regions flexibly share and manipulate event information to support the variable phenomenology of episodic memory and simulation.

Mnemoscape: Supporting Older Adults' Event Memory Using Wearable Camera Photographs on an Immersive Interface

BACKGROUND

Wearable camera photographs have been shown to be an effective memory aid in people with and without memory impairment. Most studies using wearable cameras as a memory aid have presented photographs on a computer monitor and used a written diary or no review as a comparison. In this pioneering study, we took a new and innovative approach to wearable camera photograph review that embeds the photographs within a virtual landscape. This approach may enhance these benefits by reinstating the original environmental context to increase participants' sense of re-experiencing the event.

OBJECTIVE

We compare the traditional computer monitor presentation of wearable camera photographs and actively taken digital photographs with the presentation of wearable camera photographs in a new immersive interface that reinstates the spatiotemporal context.

METHODS

Healthy older adults wore wearable or took digital photographs during a staged event. The next day and 2 weeks later, they viewed wearable camera photographs on a computer monitor or in context on an immersive interface, or digital photographs.

RESULTS

Participants who viewed wearable camera photographs in either format recalled more details during photo viewing and subsequent free recall than participants who viewed digital photographs they had taken themselves.

CONCLUSION

Wearable camera photographs are an effective support for event memory, regardless of whether they are presented in context in an experience-near format.

Neural correlates of retrieval-based enhancement of autobiographical memory in older adults

Lifelog photo review is considered to enhance the recall of personal events. While a sizable body of research has explored the neural basis of autobiographical memory (AM), there is limited neural evidence on the retrieval-based enhancement effect on event memory among older adults in the real-world environment. This study examined the neural processes of AM as was modulated by retrieval practice through lifelog photo review in older adults. In the experiment, blood-oxygen-level dependent response during subjects’ recall of recent events was recorded, where events were cued by photos that may or may not have been exposed to a priori retrieval practice (training). Subjects remembered more episodic details under the trained relative to non-trained condition. Importantly, the neural correlates of AM was exhibited by (1) dissociable cortical areas related to recollection and familiarity, and (2) a positive correlation between the amount of recollected episodic details and cortical activation within several lateral temporal and parietal regions. Further analysis of the brain activation pattern at a few regions of interest within the core remember network showed a training_condition × event_detail interaction effect, suggesting that the boosting effect of retrieval practice depended on the level of recollected event details.

A database of news videos for investigating the dynamics of emotion and memory

Emotional experiences are known to be both perceived and remembered differently from nonemotional experiences, often leading to heightened encoding of salient visual details and subjectively vivid recollection. The vast majority of previous studies have used static images to investigate how emotional event content modulates cognition, yet natural events unfold over time. Therefore, little is known about how emotion dynamically modulates continuous experience. Here we report a norming study wherein we developed a new stimulus set of 126 emotionally negative, positive, and neutral videos depicting real-life news events. Participants continuously rated the valence of each video during its presentation and judged the overall emotional intensity and valence at the end of each video. In a subsequent memory test, participants reported how vividly they could recall the video details and estimated each video's duration. We report data on the affective qualities and subjective memorability of each video. The results replicate the well-established effect that emotional experiences are remembered more vividly than nonemotional experiences. Importantly, this novel stimulus set will facilitate research into the temporal dynamics of emotional processing and memory.

Introduction to the Cognitive Abilities Account for the Reminiscence Bump in the Temporal Distribution of Autobiographical Memory

People tend to recall more specific personal events from adolescence and early adulthood than from other lifetime periods, a finding known as the reminiscence bump. Several explanations have suggested that events from the reminiscence bump are especially emotional, important, or positive, but studies using cue words have not found support for these claims. An alternative account postulates that cognitive abilities function optimally in adolescence and early adulthood, which may cause more memories to be stored in those lifetime periods. Although other studies have previously discussed the cognitive abilities account as a possible explanation for the reminiscence bump, it was only recently shown that cognitive abilities are indeed related to autobiographical memory performance. When this recent finding is combined with previous findings that cognitive abilities as well as autobiographical memory function optimally in adolescence and early adulthood, they suggest that the cognitive abilities account is a promising explanation for the reminiscence bump in the temporal distribution of word-cued memories. However, because the account does not aim to explain the reminiscence bump in the distribution of highly significant events, it should be regarded as complementary to the existing accounts.

First-person view of one's body in immersive virtual reality: Influence on episodic memory

Episodic memories (EMs) are recollections of contextually rich and personally relevant past events. EM has been linked to the sense of self, allowing one to mentally travel back in subjective time and re-experience past events. However, the sense of self has recently been linked to online multisensory processing and bodily self-consciousness (BSC). It is currently unknown whether EM depends on BSC mechanisms. Here, we used a new immersive virtual reality (VR) system that maintained the perceptual richness of life episodes and fully controlled the experimental stimuli during encoding and retrieval, including the participant’s body. Our data reveal a classical EM finding, which shows that memory for complex real-life like scenes decays over time. However, here we also report a novel finding that delayed retrieval performance can be enhanced when participants view their body as part of the virtual scene during encoding. This body effect was not observed when no virtual body or a moving control object was shown, thereby linking the sense of self, and BSC in particular, to EMs. The present VR methodology and the present behavioral findings will enable to study key aspects of EM in healthy participants and may be especially beneficial for the restoration of self-relevant memories in future experiments.

Identifying the cognitive processes underpinning hippocampal-dependent tasks

Autobiographical memory, future thinking, and spatial navigation are critical cognitive functions that are thought to be related and are known to depend upon a brain structure called the hippocampus. Surprisingly, direct evidence for their interrelatedness is lacking, as is an understanding of why they might be related. There is debate about whether they are linked by an underlying memory-related process or, as has more recently been suggested, because they each require the endogenous construction of scene imagery. Here, using a large sample of participants and multiple cognitive tests with a wide spread of individual differences in performance, we found that these functions are indeed related. Mediation analyses further showed that scene construction, and not memory, mediated (explained) the relationships between the functions. These findings offer a fresh perspective on autobiographical memory, future thinking, navigation, and also on the hippocampus, where scene imagery appears to play an influential role. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Verbal Paired Associates and the Hippocampus: The Role of Scenes

It is widely agreed that patients with bilateral hippocampal damage are impaired at binding pairs of words together. Consequently, the verbal paired associates (VPA) task has become emblematic of hippocampal function. This VPA deficit is not well understood and is particularly difficult for hippocampal theories with a visuospatial bias to explain (e.g., cognitive map and scene construction theories). Resolving the tension among hippocampal theories concerning the VPA could be important for leveraging a fuller understanding of hippocampal function. Notably, VPA tasks typically use high imagery concrete words and so conflate imagery and binding. To determine why VPA engages the hippocampus, we devised an fMRI encoding task involving closely matched pairs of scene words, pairs of object words, and pairs of very low imagery abstract words. We found that the anterior hippocampus was engaged during processing of both scene and object word pairs in comparison to abstract word pairs, despite binding occurring in all conditions. This was also the case when just subsequently remembered stimuli were considered. Moreover, for object word pairs, fMRI activity patterns in anterior hippocampus were more similar to those for scene imagery than object imagery. This was especially evident in participants who were high imagery users and not in mid and low imagery users. Overall, our results show that hippocampal engagement during VPA, even when object word pairs are involved, seems to be evoked by scene imagery rather than binding. This may help to resolve the issue that visuospatial hippocampal theories have in accounting for verbal memory.

The experience of vivid autobiographical reminiscence is supported by subjective content representations in the precuneus

The human posteromedial cortex, which includes core regions of the default mode network (DMN), is thought to play an important role in episodic memory. However, the nature and functional role of representations in these brain regions remain unspecified. Nine participants (all female) wore smartphone devices to record episodes from their daily lives for multiple weeks, each night indicating the personally-salient attributes of each episode. Participants then relived their experiences in an fMRI scanner cued by images from their own lives. Representational Similarity Analysis revealed a broad network, including parts of the DMN, that represented personal semantics during autobiographical reminiscence. Within this network, activity in the right precuneus reflected more detailed representations of subjective contents during vivid relative to non-vivid, recollection. Our results suggest a more specific mechanism underlying the phenomenology of vivid autobiographical reminiscence, supported by rich subjective content representations in the precuneus, a hub of the DMN previously implicated in metacognitive evaluations during memory retrieval.

Open monitoring meditation reduces the involvement of brain regions related to memory function

Mindfulness meditation consists of focused attention meditation (FAM) and open monitoring meditation (OMM), both of which reduce activation of the default mode network (DMN) and mind-wandering. Although it is known that FAM requires intentional focused attention, the mechanisms of OMM remain largely unknown. To investigate this, we examined striatal functional connectivity in 17 experienced meditators (mean total practice hours = 920.6) during pre-resting, meditation, and post-resting states comparing OMM with FAM, using functional magnetic resonance imaging. Both FAM and OMM reduced functional connectivity between the striatum and posterior cingulate cortex, which is a core hub region of the DMN. Furthermore, OMM reduced functional connectivity of the ventral striatum with both the visual cortex related to intentional focused attention in the attentional network and retrosplenial cortex related to memory function in the DMN. In contrast, FAM increased functional connectivity in these regions. Our findings suggest that OMM reduces intentional focused attention and increases detachment from autobiographical memory. This detachment may play an important role in non-judgmental and non-reactive attitude during OMM. These findings provide new insights into the mechanisms underlying the contribution of OMM to well-being and happiness.

Neural responses to emotional involuntary memories in posttraumatic stress disorder: Differences in timing and activity

Background

Involuntary memories are a hallmark symptom of posttraumatic stress disorder (PTSD), but studies of the neural basis of involuntary memory retrieval in posttraumatic stress disorder (PTSD) are sparse. The study of the neural correlates of involuntary memories of stressful events in PTSD focuses on the voluntary retrieval of memories that are sometimes recalled as intrusive involuntary memories, not on involuntary retrieval while being scanned. Involuntary memory retrieval in controls has been shown to elicit activity in the parahippocampal gyrus, precuneus, inferior parietal cortex, and posterior midline regions. However, it is unknown whether involuntary memories are supported by the same mechanisms in PTSD. Because previous work has shown that both behavioral and neural responsivity is slowed in PTSD, we examined the spatiotemporal dynamics of the neural activity underlying negative and neutral involuntary memory retrieval.

Methods

Twenty-one individuals with PTSD and 21 non-PTSD, trauma-exposed controls performed an involuntary memory task, while undergoing a functional magnetic resonance imaging scan. Environmental sounds served as cues for well-associated pictures of negative and neutral scenes. We used a finite impulse response model to analyze temporal differences between groups in neural responses.

Results

Compared with controls, participants with PTSD reported more involuntary memories, which were more emotional and more vivid, but which activated a similar network of regions. However, compared to controls, individuals with PTSD showed delayed neural responsivity in this network and increased vmPFC/ACC activity for negative > neutral stimuli.

Conclusions

The similarity between PTSD and controls in neural substrates underlying involuntary memories suggests that, unlike voluntary memories, involuntary memories elicit similar activity in regions critical for memory retrieval. Further, the delayed neural responsivity for involuntary memories in PTSD suggests that factors affecting cognition in PTSD, like increased fatigue, or avoidance behaviors could do so by delaying activity in regions necessary for cognitive processing. Finally, compared to neutral memories, negative involuntary memories elicit hyperactivity in the vmPFC, whereas the vmPFC is typically shown to be hypoactive in PTSD during voluntary memory retrieval. These patterns suggest that considering both the temporal dynamics of cognitive processes as well as involuntary cognitive processes would improve existing neurobiological models of PTSD.

Temporal Dissociation of Neocortical and Hippocampal Contributions to Mental Time Travel Using Intracranial Recordings in Humans

In mental time travel (MTT) one is “traveling” back-and-forth in time, remembering, and imagining events. Despite intensive research regarding memory processes in the hippocampus, it was only recently shown that the hippocampus plays an essential role in encoding the temporal order of events remembered, and therefore plays an important role in MTT. Does it also encode the temporal relations of these events to the remembering self? We asked patients undergoing pre-surgical evaluation with depth electrodes penetrating the temporal lobes bilaterally toward the hippocampus to project themselves in time to a past, future, or present time-point, and then make judgments regarding various events. Classification analysis of intracranial evoked potentials revealed clear temporal dissociation in the left hemisphere between lateral-temporal electrodes, activated at ~100–300 ms, and hippocampal electrodes, activated at ~400–600 ms. This dissociation may suggest a division of labor in the temporal lobe during self-projection in time, hinting toward the different roles of the lateral-temporal cortex and the hippocampus in MTT and the temporal organization of the related events with respect to the experiencing self.

Attachment Security in Infancy: A Preliminary Study of Prospective Links to Brain Morphometry in Late Childhood

A large body of longitudinal research provides compelling evidence for the critical role of early attachment relationships in children’s social, emotional, and cognitive development. It is expected that parent–child attachment relationships may also impact children’s brain development, however, studies linking normative caregiving experiences and brain structure are scarce. To our knowledge, no study has yet examined the associations between the quality of parent–infant attachment relationships and brain morphology during childhood. The aim of this preliminary study was to investigate the prospective links between mother–infant attachment security and whole-brain gray matter (GM) volume and thickness in late childhood. Attachment security toward the mother was assessed in 33 children when they were 15 months old. These children were then invited to undergo structural magnetic resonance imaging at 10–11 years of age. Results indicated that children more securely attached to their mother in infancy had larger GM volumes in the superior temporal sulcus and gyrus, temporo-parietal junction, and precentral gyrus in late childhood. No associations between attachment security and cortical thickness were found. If replicated, these results would suggest that a secure attachment relationship and its main features (e.g., adequate dyadic emotion regulation, competent exploration) may influence GM volume in brain regions involved in social, cognitive, and emotional functioning through experience-dependent processes.

Human pursuance of equality hinges on mental processes of projecting oneself into the perspectives of others and into future situations

In the pursuance of equality, behavioural scientists disagree about distinct motivators, that is, consideration of others and prospective calculation for oneself. However, accumulating data suggest that these motivators may share a common process in the brain whereby perspectives and events that did not arise in the immediate environment are conceived. To examine this, we devised a game imitating a real decision-making situation regarding redistribution among income classes in a welfare state. The neural correlates of redistributive decisions were examined under contrasting conditions, with and without uncertainty, which affects support for equality in society. The dorsal anterior cingulate cortex (dACC) and the caudate nucleus were activated by equality decisions with uncertainty but by selfless decisions without uncertainty. Activation was also correlated with subjective values. Activation in both the dACC and the caudate nucleus was associated with the attitude to prefer accordance with others, whereas activation in the caudate nucleus reflected that the expected reward involved the prospective calculation of relative income. The neural correlates suggest that consideration of others and prospective calculation for oneself may underlie the support for equality. Projecting oneself into the perspective of others and into prospective future situations may underpin the pursuance of equality.

Are There Multiple Kinds of Episodic Memory? An fMRI Investigation Comparing Autobiographical and Recognition Memory Tasks

What brain regions underlie retrieval from episodic memory? The bulk of research addressing this question with fMRI has relied upon recognition memory for materials encoded within the laboratory. Another, less dominant tradition has used autobiographical methods, whereby people recall events from their lifetime, often after being cued with words or pictures. The current study addresses how the neural substrates of successful memory retrieval differed as a function of the targeted memory when the experimental parameters were held constant in the two conditions (except for instructions). Human participants studied a set of scenes and then took two types of memory test while undergoing fMRI scanning. In one condition (the picture memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it was recollected from the prior study episode. In a second condition (the life memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it reminded them of a specific event from their preexperimental lifetime. An examination of successful retrieval (yes responses) for recently studied scenes for the two test types revealed pronounced differences; that is, autobiographical retrieval instantiated with the life memory test preferentially activated the default mode network, whereas hits in the picture memory test preferentially engaged the parietal memory network as well as portions of the frontoparietal control network. When experimental cueing parameters are held constant, the neural underpinnings of successful memory retrieval differ when remembering life events and recently learned events.SIGNIFICANCE STATEMENT Episodic memory is often discussed as a solitary construct. However, experimental traditions examining episodic memory use very different approaches, and these are rarely compared to one another. When the neural correlates associated with each approach have been directly contrasted, results have varied considerably and at times contradicted each other. The present experiment was designed to match the two primary approaches to studying episodic memory in an unparalleled manner. Results suggest a clear separation of systems supporting memory as it is typically tested in the laboratory and memory as assessed under autobiographical retrieval conditions. These data provide neurobiological evidence that episodic memory is not a single construct, challenging the degree to which different experimental traditions are studying the same construct.

Decoding fMRI Signatures of Real-world Autobiographical Memory Retrieval

Extant neuroimaging data implicate frontoparietal and medial-temporal lobe regions in episodic retrieval, and the specific pattern of activity within and across these regions is diagnostic of an individual's subjective mnemonic experience. For example, in laboratory-based paradigms, memories for recently encoded faces can be accurately decoded from single-trial fMRI patterns [Uncapher, M. R., Boyd-Meredith, J. T., Chow, T. E., Rissman, J., & Wagner, A. D. Goal-directed modulation of neural memory patterns: Implications for fMRI-based memory detection. Journal of Neuroscience, 35, 8531–8545, 2015; Rissman, J., Greely, H. T., & Wagner, A. D. Detecting individual memories through the neural decoding of memory states and past experience. Proceedings of the National Academy of Sciences, U.S.A., 107, 9849–9854, 2010]. Here, we investigated the neural patterns underlying memory for real-world autobiographical events, probed at 1- to 3-week retention intervals as well as whether distinct patterns are associated with different subjective memory states. For 3 weeks, participants (n = 16) wore digital cameras that captured photographs of their daily activities. One week later, they were scanned while making memory judgments about sequences of photos depicting events from their own lives or events captured by the cameras of others. Whole-brain multivoxel pattern analysis achieved near-perfect accuracy at distinguishing correctly recognized events from correctly rejected novel events, and decoding performance did not significantly vary with retention interval. Multivoxel pattern classifiers also differentiated recollection from familiarity and reliably decoded the subjective strength of recollection, of familiarity, or of novelty. Classification-based brain maps revealed dissociable neural signatures of these mnemonic states, with activity patterns in hippocampus, medial PFC, and ventral parietal cortex being particularly diagnostic of recollection. Finally, a classifier trained on previously acquired laboratory-based memory data achieved reliable decoding of autobiographical memory states. We discuss the implications for neuroscientific accounts of episodic retrieval and comment on the potential forensic use of fMRI for probing experiential knowledge.

The Role of Perspective in Mental Time Travel

Recent years have seen accumulating evidence for the proposition that people process time by mapping it onto a linear spatial representation and automatically “project” themselves on an imagined mental time line. Here, we ask whether people can adopt the temporal perspective of another person when travelling through time. To elucidate similarities and differences between time travelling from one's own perspective or from the perspective of another person, we asked participants to mentally project themselves or someone else (i.e., a coexperimenter) to different time points. Three basic properties of mental time travel were manipulated: temporal location (i.e., where in time the travel originates: past, present, and future), motion direction (either backwards or forwards), and temporal duration (i.e., the distance to travel: one, three, or five years). We found that time travels originating in the present lasted longer in the self- than in the other-perspective. Moreover, for self-perspective, but not for other-perspective, time was differently scaled depending on where in time the travel originated. In contrast, when considering the direction and the duration of time travelling, no dissimilarities between the self- and the other-perspective emerged. These results suggest that self- and other-projection, despite some differences, share important similarities in structure.

Conversations between self and self as Sigmund Freud--A virtual body ownership paradigm for self counselling

When people see a life-sized virtual body (VB) from first person perspective in virtual reality they are likely to have the perceptual illusion that it is their body. Additionally such virtual embodiment can lead to changes in perception, implicit attitudes and behaviour based on attributes of the VB. To date the changes that have been studied are as a result of being embodied in a body representative of particular social groups (e.g., children and other race). In our experiment participants alternately switched between a VB closely resembling themselves where they described a personal problem, and a VB representing Dr Sigmund Freud, from which they offered themselves counselling. Here we show that when the counsellor resembles Freud participants improve their mood, compared to the counsellor being a self-representation. The improvement was greater when the Freud VB moved synchronously with the participant, compared to asynchronously. Synchronous VB movement was associated with a much stronger illusion of ownership over the Freud body. This suggests that this form of embodied perspective taking can lead to sufficient detachment from habitual ways of thinking about personal problems, so as to improve the outcome, and demonstrates the power of virtual body ownership to effect cognitive changes.

Human hippocampus represents space and time during retrieval of real-world memories

Memory stretches over a lifetime. In controlled laboratory settings, the hippocampus and other medial temporal lobe brain structures have been shown to represent space and time on the scale of meters and seconds. It remains unclear whether the hippocampus also represents space and time over the longer scales necessary for human episodic memory. We recorded neural activity while participants relived their own experiences, cued by photographs taken with a custom lifelogging device. We found that the left anterior hippocampus represents space and time for a month of remembered events occurring over distances of up to 30 km. Although previous studies have identified similar drifts in representational similarity across space or time over the relatively brief time scales (seconds to minutes) that characterize individual episodic memories, our results provide compelling evidence that a similar pattern of spatiotemporal organization also exists for organizing distinct memories that are distant in space and time. These results further support the emerging view that the anterior, as opposed to posterior, hippocampus integrates distinct experiences, thereby providing a scaffold for encoding and retrieval of autobiographical memories on the scale of our lives.

Detecting Knowledge of Incidentally Acquired, Real-World Memories Using a P300-Based Concealed-Information Test

Autobiographical memory for events experienced during normal daily life has been studied at the group level, but no studies have yet examined the ability to detect recognition of incidentally acquired memories among individual subjects. We present the first such study here, which employed a concealed-information test in which subjects were shown words associated with activities they had experienced the previous day. Subjects wore a video-recording device for 4 hr on Day 1 and then returned to the laboratory on Day 2, where they were shown words relating to events recorded with the camera (probe items) and words of the same category but not relating to the subject’s activities (irrelevant items). Electroencephalograms were recorded, and presentation of probe items was associated with a large peak in the amplitude of the P300 component. We were able to discriminate perfectly between 12 knowledgeable subjects who viewed stimuli related to their activities and 12 nonknowledgeable subjects who viewed only irrelevant items. These results have strong implications for the use of memory-detection paradigms in criminal contexts.

Age-related sensitivity to task-related modulation of language-processing networks

It is widely assumed that cognitive functions decline with age and that these decrements are associated with age-related changes in patterns of functional activity. However, these functional changes may be due to age-related increased responsiveness to task demands and not to other cognitive processes on which neural and behavioural responses rely, since many ageing studies use task paradigms that may not be orthogonal to the cognitive function being investigated. Here we test this hypothesis in adults aged 20–86 years by combining measures of language comprehension, functional connectivity and neural integrity to identify functional networks activated in two language experiments with varying task demands. In one, participants listened to spoken sentences without performing an overt task (the natural listening condition) while in the other they performed a task in response to the same sentences. Using task-based ICA of fMRI, we identified a left-lateralised frontotemporal network associated with syntactic analysis, which remained consistently activated regardless of task demands. In contrast, in the task condition only a separate set of components showed task-specific activity in Opercular, Frontoparietal, and bilateral PFC. Only the PFC showed age-related increases in activation which, furthermore, was strongly mediated by grey matter health. These results suggest that, contrary to prevailing views, age-related changes in cognitive activation may be due in part to differential responses to task-related processes.

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Ageing effects on brain activity may be over-estimated due to demands of tasks.

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Age differences in PFC network activity were present only during an active task.

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This age-related increase is largely accounted for by grey matter morphology.

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Results suggest that age-related changes may be due to task-related processes.

Neural networks supporting autobiographical memory retrieval in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) affects the functional recruitment and connectivity between neural regions during autobiographical memory (AM) retrieval that overlap with default and control networks. Whether such univariate changes relate to potential differences in the contributions of the large-scale neural networks supporting cognition in PTSD is unknown. In the present functional MRI study, we employed independent-component analysis to examine the influence of the engagement of neural networks during the recall of personal memories in a PTSD group (15 participants) as compared to non-trauma-exposed healthy controls (14 participants). We found that the PTSD group recruited similar neural networks when compared to the controls during AM recall, including default-network subsystems and control networks, but group differences emerged in the spatial and temporal characteristics of these networks. First, we found spatial differences in the contributions of the anterior and posterior midline across the networks, and of the amygdala in particular, for the medial temporal subsystem of the default network. Second, we found temporal differences within the medial prefrontal subsystem of the default network, with less temporal coupling of this network during AM retrieval in PTSD relative to controls. These findings suggest that the spatial and temporal characteristics of the default and control networks potentially differ in a PTSD group versus healthy controls and contribute to altered recall of personal memory.

FMRI contributions to addressing autobiographical memory impairment in temporal lobe pathology

Episodic autobiographical memory (AM) allows one, through the recollection of sensory-perceptual details, thoughts and feelings, to become aware of an event as belonging to one’s own past as well as being able to project into one’s future. Because AM provides a sense of self-continuity, contributes to the integrity of the self, and helps predicting future experiences, any deficit of AM may have debilitating consequences for everyday life functioning. Understanding AM failure and the underlying neural mechanisms has the potential to shed light on brain reorganization mechanisms and engagement of compensatory processes. Functional magnetic resonance imaging (fMRI) provides the most promising imaging method to tackle these issues. We reviewed evidence from the few studies that used fMRI to investigate the functionality of the residual tissue, the neural reorganization and compensatory mechanisms in patients with neurological conditions due to impaired medial temporal lobe. Overall, these studies highlight the importance of the left hippocampus, which when atrophied and not functional leads to AM deficits but its residual functionality may support relatively normal AM recollection. When damaged hippocampal tissue is not functional, other brain regions (e.g., the medial prefrontal cortex) may be involved to compensate impairment, but they appear generally ineffective to support detailed episodic recollection.

Bayesian network analysis reveals alterations to default mode network connectivity in individuals at risk for Alzheimer's disease

Alzheimer's disease (AD) is associated with abnormal functioning of the default mode network (DMN). Functional connectivity (FC) changes to the DMN have been found in patients with amnestic mild cognitive impairment (aMCI), which is the prodromal stage of AD. However, whether or not aMCI also alters the effective connectivity (EC) of the DMN remains unknown. We employed a combined group independent component analysis (ICA) and Bayesian network (BN) learning approach to resting-state functional MRI (fMRI) data from 17 aMCI patients and 17 controls, in order to establish the EC pattern of DMN, and to evaluate changes occurring in aMCI. BN analysis demonstrated heterogeneous regional convergence degree across DMN regions, which were organized into two closely interacting subsystems. Compared to controls, the aMCI group showed altered directed connectivity weights between DMN regions in the fronto-parietal, temporo-frontal, and temporo-parietal pathways. The aMCI group also exhibited altered regional convergence degree in the right inferior parietal lobule. Moreover, we found EC changes in DMN regions in aMCI were correlated with regional FC levels, and the connectivity metrics were associated with patients' cognitive performance. This study provides novel sights into our understanding of the functional architecture of the DMN and adds to a growing body of work demonstrating the importance of the DMN as a mechanism of aMCI.

Neural mechanisms of reactivation-induced updating that enhance and distort memory

We remember a considerable number of personal experiences because we are frequently reminded of them, a process known as memory reactivation. Although memory reactivation helps to stabilize and update memories, reactivation may also introduce distortions if novel information becomes incorporated with memory. Here we used functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms mediating reactivation-induced updating in memory for events experienced during a museum tour. During scanning, participants were shown target photographs to reactivate memories from the museum tour followed by a novel lure photograph from an alternate tour. Later, participants were presented with target and lure photographs and asked to determine whether the photographs showed a stop they visited during the tour. We used a subsequent memory analysis to examine neural recruitment during reactivation that was associated with later true and false memories. We predicted that the quality of reactivation, as determined by online ratings of subjective recollection, would increase subsequent true memories but also facilitate incorporation of the lure photograph, thereby increasing subsequent false memories. The fMRI results revealed that the quality of reactivation modulated subsequent true and false memories via recruitment of left posterior parahippocampal, bilateral retrosplenial, and bilateral posterior inferior parietal cortices. However, the timing of neural recruitment and the way in which memories were reactivated contributed to differences in whether memory reactivation led to distortions or not. These data reveal the neural mechanisms recruited during memory reactivation that modify how memories will be subsequently retrieved, supporting the flexible and dynamic aspects of memory.

Dissociable neural processes underlying risky decisions for self versus other

Previous neuroimaging studies on decision making have mainly focused on decisions on behalf of oneself. Considering that people often make decisions on behalf of others, it is intriguing that there is little neurobiological evidence on how decisions for others differ from those for oneself. The present study directly compared risky decisions for self with those for another person using functional magnetic resonance imaging (fMRI). Participants were asked to perform a gambling task on behalf of themselves (decision-for-self condition) or another person (decision-for-other condition) while in the scanner. Their task was to choose between a low-risk option (i.e., win or lose 10 points) and a high-risk option (i.e., win or lose 90 points) with variable levels of winning probability. Compared with choices regarding others, those regarding oneself were more risk-averse at lower winning probabilities and more risk-seeking at higher winning probabilities, perhaps due to stronger affective process during risky decisions for oneself compared with those for other. The brain-activation pattern changed according to the target, such that reward-related regions were more active in the decision-for-self condition than in the decision-for-other condition, whereas brain regions related to the theory of mind (ToM) showed greater activation in the decision-for-other condition than in the decision-for-self condition. Parametric modulation analysis using individual decision models revealed that activation of the amygdala and the dorsomedial prefrontal cortex (DMPFC) were associated with value computations for oneself and for another, respectively, during risky financial decisions. The results of the present study suggest that decisions for oneself and for other may recruit fundamentally distinct neural processes, which can be mainly characterized as dominant affective/impulsive and cognitive/regulatory processes, respectively.

Theory of mind

Theory of mind and its development has been a significantly important-and challenging-topic of research in cognitive science for three decades. This review summarizes our knowledge of when and how children come to understand their own and others' minds, including the developmental timetable, old and new measures, and foundational skills in infancy. We review recent research on theory-of-mind (ToM) and learning, that is, ways in which children's understanding of other minds informs how they learn about the world, as well as evidence for an important role of domain-general cognitive skills (executive function) in the development of ToM, and the neural networks that are most strongly implicated. Finally, we propose future directions for research in this vast and growing field. WIREs Cogn Sci 2013, 4:391-402. doi: 10.1002/wcs.1232 The authors have declared no conflicts of interest for this article. For further resources related to this article, please visit the WIREs website.

Modifying memory: selectively enhancing and updating personal memories for a museum tour by reactivating them

Memory can be modified when reactivated, but little is known about how the properties and extent of reactivation can selectively affect subsequent memory. We developed a novel museum paradigm to directly investigate reactivation-induced plasticity for personal memories. Participants reactivated memories triggered by photos taken from a camera they wore during a museum tour and made relatedness judgments on novel photos taken from a different tour of the same museum. Subsequent recognition memory for events at the museum was better for memories that were highly reactivated (i.e., the retrieval cues during reactivation matched the encoding experience) than for memories that were reactivated at a lower level (i.e., the retrieval cues during reactivation mismatched the encoding experience), but reactivation also increased false recognition of photographs depicting stops that were not experienced during the museum tour. Reactivation thus enables memories to be selectively enhanced and distorted via updating, thereby supporting the dynamic and flexible nature of memory.

Individualized Theory of Mind (iToM): When Memory Modulates Empathy

Functional neuroimaging studies have noted that brain regions supporting theory of mind (ToM) overlap remarkably with those underlying episodic memory, suggesting a link between the two processes. The present study shows that memory for others’ past experiences modulates significantly our appraisal of, and reaction to, what is happening to them currently. Participants read the life story of two characters; one had experienced a long series of love-related failures, the other a long series of work-related failures. In a later faux pas recognition task, participants reported more empathy for the character unlucky in love in love-related faux pas scenarios, and for the character unlucky at work in work-related faux pas scenarios. The memory-based modulation of empathy correlated with the number of details remembered from the characters’ life story. These results suggest that individuals use memory for other people’s past experiences to simulate how they feel in similar situations they are currently facing. The integration of ToM and memory processes allows adjusting mental state inferences to fit unique social targets, constructing an individualized ToM.

Imagining Other People's Experiences in a Person with Impaired Episodic Memory: The Role of Personal Familiarity

Difficulties remembering one’s own experiences via episodic memory may affect the ability to imagine other people’s experiences during theory of mind (ToM). Previous work shows that the same set of brain regions recruited during tests of episodic memory and future imagining are also engaged during standard laboratory tests of ToM. However, hippocampal amnesic patients who show deficits in past and future thinking, show intact performance on ToM tests, which involve unknown people or fictional characters. Here we present data from a developmental amnesic person (H.C.) and a group of demographically matched controls, who were tested on a naturalistic test of ToM that involved describing other people’s experiences in response to photos of personally familiar others (“pToM” condition) and unfamiliar others (“ToM” condition). We also included a condition that involved recollecting past experiences in response to personal photos (“EM” condition). Narratives were scored using an adapted Autobiographical Interview scoring procedure. Due to the visually rich stimuli, internal details were further classified as either descriptive (i.e., details that describe the visual content of the photo) or elaborative (i.e., details that go beyond what is visually depicted in the photo). Relative to controls, H.C. generated significantly fewer elaborative details in response to the pToM and EM photos and an equivalent number of elaborative details in response to the ToM photos. These data converge with previous neuroimaging results showing that the brain regions underlying pToM and episodic memory overlap to a greater extent than those supporting ToM. Taken together, these results suggest that detailed episodic representations supported by the hippocampus may be pivotal for imagining the experiences of personally familiar, but not unfamiliar, others.