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We consider a model of associative storage and retrieval of compositional memories in an extended cortical network. Our model network is comprised of Potts units, which represent patches of cortex, interacting through long-range connections. The critical assumption is that a memory is composed of a limited number of items, each of which has a pre-established representation: storing a new memory only involves acquiring the connections, if novel, among the participating items. The model is shown to have a much lower storage capacity than when it stores simple unitary representations. It is also shown that an input from the hippocampus facilitates associative retrieval. When it is absent, it is advantageous to cue rare rather than frequent items. The implications of these results for emerging trends in empirical research are discussed.

Is progress in understanding the neural basis for spatial navigation relevant to the human language faculty? Not so much at the shortest scale, where movement is continuous, a recent study in the space of vowels suggests. At a much larger scale, however, that of the verbalization of run-away thoughts, a rich phenomenology appears to involve critical contributions by some of the brain structures also involved in spatial cognition. Their interactions may have to be approached with models operating at an integrated cortical level and allowing for the compositionality of multiple local attractor states. A useful window on the latching dynamics enabled by cortico-cortical interactions may be offered by altered states of consciousness. As an example, psychedelic states have been reported to alter the graph properties of functional connectivity in the cortex so as to facilitate wide-ranging trips.

Intertemporal choices require trade-offs between short-term and long-term outcomes. Ventromedial prefrontal cortex (vmPFC) damage causes steep discounting of future rewards (delay discounting; DD) and impoverished episodic future thinking (EFT). The role of vmPFC in reward valuation, EFT, and their interaction during intertemporal choice is still unclear. Here, twelve patients with lesions to vmPFC and forty-one healthy controls chose between smaller-immediate and larger-delayed hypothetical monetary rewards while we manipulated reward magnitude and the availability of EFT cues. In the EFT condition, participants imagined personal events to occur at the delays associated with the larger-delayed rewards. We found that DD was steeper in vmPFC patients compared to controls, and not modulated by reward magnitude. However, EFT cues downregulated DD in vmPFC patients as well as controls. These findings indicate that vmPFC integrity is critical for the valuation of (future) rewards, but not to instill EFT in intertemporal choice.

Self-related information is remembered better than other-related information (self-reference effect; SRE), a phenomenon that has been convincingly linked to the medial prefrontal cortex. It is not clear whether information related to our future self would also have a privileged status in memory, as medial prefrontal cortex (mPFC) regions respond less to the future than to the present self, as if it were an ‘other’. Here we ask whether the integrity of the ventral mPFC (vmPFC) is necessary for the emergence of the present and future SRE, if any. vmPFC patients and brain-damaged and healthy controls judged whether each of a series of trait adjectives was descriptive of their present self, future self, another person and that person in the future and later recognized studied traits among distractors. Information relevant to the present (vs future) was generally recognized better, across groups. However, whereas healthy and brain-damaged controls exhibited strong present and future SREs, these were absent in vmPFC patients, who concomitantly showed reduced certainty about their own present and anticipated traits compared to the control groups. These findings indicate that vmPFC is necessary to impart a special mnemonic status to self-related information, including our envisioned future self, possibly by instantiating the self-schema.

The role of ventromedial prefrontal cortex (vmPFC) in mental time travel toward the past and the future is debated. Here, patients with focal lesions to the vmPFC and brain-damaged and healthy controls mentally projected themselves to a past, present or future moment of subjective time (self-projection) and classified a series of events as past or future relative to the adopted temporal self-location (self-reference). We found that vmPFC patients were selectively impaired in projecting themselves to the future and in recognizing relative-future events. These findings indicate that vmPFC damage hinders the mental processing of and movement toward future events, pointing to a prominent, multifaceted role of vmPFC in future-oriented mental time travel.

We investigated episodic future thinking (EFT) and future-based cognition and decision-making in patient SG, who developed a dense retrograde amnesia following hypoxia due to a cardiac arrest. Despite intact general cognitive and executive functioning, SG was unable to remember events from his entire lifetime. He had, however, relatively spared anterograde memory and general semantic knowledge. Voxel-based morphometry detected a reduction of gray matter in the thalamus, cerebellum and fusiform gyrus bilaterally, and, at a reduced threshold, in several regions of the autobiographical memory network, including the hippocampi. We show that SG is unable to imagine personal future events, but can imagine fictitious events not self-relevant and not located in subjective time. Despite severely impaired EFT, SG shows normal attitudes towards the future time, and normal delay discounting rates. These findings suggest that retrieval of autobiographical information from long-term memory is necessary for EFT. However, relatively spared anterograde memory and general semantic knowledge may be sufficient to allow construction of fictitious experiences. As well, EFT is not necessary to drive future-oriented cognition and choice. These findings highlight the relation between autobiographical memory and EFT, and the fractionation of human temporal consciousness. Moreover, they contribute to our understanding of retrograde amnesia as an impairment of memory as well as future thinking.

This study investigated whether damage to the posterior parietal cortex (PPC) impairs the capacity to retrieve multiple aspects of the encoding context in which items were studied, or whether it impairs the subjective awareness of recollection. Patients with lesions to the PPC (PPC patients) and healthy controls memorized words along with the position in which the words were presented on the screen and the ink color in which they were printed. We studied PPC patients' recognition and source memory performance, as well as subjective recollection as indexed by Remember/Know judgments. PPC patients had preserved recognition memory, and gave a similar number of R responses as did controls. Moreover, PPC patients' source memory performance, including memory for multiple contextual features, was similar to the controls'. However, whereas healthy controls were more likely to select R responses with correct multifeatural source judgments compared to K responses, PPC patients were not. These findings indicate that the PPC plays a role in the subjective experience and metamnemonic evaluation of memory contents.

The ventral (VPC) and dorsal sectors of the posterior parietal cortex are long known to mediate bottom-up and top-down attention to the external space. Because these regions also are implicated in retrieval of episodic memories, we proposed they also mediate attention to the internal (memory) space. One objection to this Attention to Memory hypothesis is that parietal regions involved in directing attention to percepts and memory are spatially adjacent but not overlapping, suggesting that different neural mechanisms are involved in each. This misalignment is most pronounced in VPC. Here, we re-examine fMRI data, and show that (1) different VPC subregions are associated with different aspects of bottom-up attention to the external space, (2) only VPC subregions showing invalid cue (but not oddball) effects overlap with those associated with episodic memory retrieval, leading us to conclude that (3) the same regions that signal unexpected percepts also signal unexpected memories. These findings are consistent with the 'overarching view' of VPC as deploying bottom-up attention during both perception and episodic memory retrieval, and suggest that the degree of anatomical convergence across the two domains depends on the correspondence between the specific bottom-up attention demands of perceptual and memory tasks.

Functional neuroimaging research has consistently associated brain structures within the default mode network (DMN) and frontoparietal network (FPN) with mind-wandering. Targeted lesion research has documented impairments in mind-wandering after damage to the medial prefrontal cortex (mPFC) and hippocampal regions associated with the DMN. However, no lesion studies to date have applied lesion network mapping to identify common networks associated with deficits in mind-wandering. In lesion network mapping, resting-state functional connectivity data from healthy participants are used to infer which brain regions are functionally connected to each lesion location from a sample with brain injury. In the current study, we conducted a lesion network mapping analysis to test the hypothesis that lesions affecting the DMN and FPN would be associated with diminished mind-wandering. We assessed mind-wandering frequency on the Imaginal Processes Inventory (IPI) in participants with brain injury (n = 29) and healthy comparison participants without brain injury (n = 19). Lesion network mapping analyses showed the strongest association of reduced mind-wandering with the left inferior parietal lobule within the DMN. In addition, traditional lesion symptom mapping results revealed that reduced mind-wandering was associated with lesions of the dorsal, ventral, and anterior sectors of mPFC, parietal lobule, and inferior frontal gyrus in the DMN (p < 0.05 uncorrected). These findings provide novel lesion support for the role of the DMN in mind-wandering and contribute to a burgeoning literature on the neural correlates of spontaneous cognition.

OBJECTIVE: Functional neuroimaging and lesion studies show that the ventromedial prefrontal cortex (vmPFC) is implicated in episodic future thinking (EFT), yet its role remains unclear. In this study, we sought to (a) confirm recent findings of impaired EFT in patients with lesions to the vmPFC (vmPFC patients) using a new task, and (b) investigate the influence of nonepisodic mechanisms, namely, narrative construction and working memory maintenance, on vmPFC patients' EFT performance. METHOD: vmPFC patients and healthy participants imagined future events using pictures as cues, described pictures, or described pictures while maintaining them in working memory after an observation phase. RESULTS: Compared with the controls, vmPFC patients produced less specific reports across all conditions, as indicated by fewer internal (episodic) but a similar number of external (semantic) details. However, controlling for description and working memory performance did not eliminate group differences in EFT. Moreover, vmPFC damage reduced the proportion of internal-to-total details for EFT only. CONCLUSIONS: These results indicate that EFT problems in vmPFC patients are not merely the reflection of problems in maintaining in working memory and narrating events, but, more likely, of an impairment upstream, in creating novel events. (PsycINFO Database Record

The ability to project oneself into the past and future to relive or pre-live personal experiences, known as mental time travel (MTT), is associated with activity in a core network of brain regions involving the ventromedial prefrontal cortex (vmPFC). We investigated whether (1) vmPFC is crucial for MTT, and (2) whether vmPFC is selectively involved in the construction of self-relevant events or also mediates construction of events happening to others. Patients with lesions to vmPFC (vmPFC patients) and healthy controls remembered personal past events and imagined personal future events across different timeframes, and imagined events to happen to a close or a distant other. Compared to the controls, vmPFC patients were impaired at constructing both past and future events, indicating that vmPFC is critical for MTT. vmPFC patients' ability to imagine personal future events was related to patients' temporal discounting rates. Patients, however, were also impaired at imagining other-related events, suggesting that self-relevance may not be a critical factor in explaining vmPFC's involvement in MTT. We suggest that vmPFC is crucial for the imagination of complex experiences alternative to the current reality, which serves construction of both self-relevant and other-relevant events.

Mind-wandering, an ubiquitous expression of humans' mental life, reflects a drift of attention away from the current task towards self-generated thoughts, and has been associated with activity in the brain default network. To date, however, little is understood about the contribution of individual nodes of this network to mind-wandering. Here, we investigated whether the ventromedial prefrontal cortex (vmPFC) is critically involved in mind-wandering, by studying the propensity to mind-wander in patients with lesion to the vmPFC (vmPFC patients), control patients with lesions not involving the vmPFC, and healthy individuals. Participants performed three tasks varying in cognitive demands while their thoughts were periodically sampled, and a self-report scale of daydreaming in daily life. vmPFC patients exhibited reduced mind-wandering rates across tasks, and claimed less frequent daydreaming, than both healthy and brain-damaged controls. vmPFC damage reduced off-task thoughts related to the future, while it promoted those about the present. These results indicate that vmPFC critically supports mind-wandering, possibly by helping to construct future-related scenarios and thoughts that have the potential to draw attention inward, away from the ongoing tasks.

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The thought of one’s own death induces anxiety and threatens self-esteem. According to Terror Management Theory (TMT), to reduce this existential threat individuals (1) adhere more strongly to their cultural worldview and (2) embrace behaviors aimed at boosting self-esteem. Previous psychological studies of TMT do not generally rely on incentive-compatible mechanisms. However, economic incentives are strong drivers of individuals’ behavior and need to be studied along with intrinsic motivations. Here, we combined—for the first time—a real effort task with psychological priming techniques. Crucially, we adopted a “flat-wage” scheme to investigate whether individuals primed with death-related thoughts, i.e., a Mortality Salience (MS) induction, increase their individual productivity more than individuals primed with a control topic (Music salience induction). We also investigated whether the effect of MS on performance is mainly driven by the quest for self-esteem vs. status-seeking, providing either private or public feedback on performance. Participants generally showed lower performance levels in the MS compared to the control condition. Public feedback bolstered performance, but its effect was milder under MS. These results suggest that in the absence of economic incentives to perform, individuals do not generally increase effort and productivity; they rather adhere more tightly to cultural (materialistic) worldviews, avoiding effort that is not compensated. The effect of MS, indeed, was strongly influenced by individual materialism.

The ventromedial prefrontal cortex (vmPFC) is known to play a key role in reward processing and decision making. However, its relative contribution to affect-rich ("hot") and affect-poor ("cold") decisions is not fully understood. Damage to vmPFC is associated with impaired performance on laboratory tasks of decision making under ambiguity and risk. In the current study, we tested the hypothesis that vmPFC is critical for adaptive risk taking under "hot" conditions specifically. Participants included patients with focal lesions in vmPFC, patient controls with damage in regions not including vmPFC, and healthy controls. They completed hot and cold versions of a dynamic risk-taking task, the Columbia Card Task (CCT). Relative to healthy controls and patient controls, vmPFC patients showed a strong overall increase in risk taking in the hot version of the CCT, despite preserved sensitivity to trial-level variation in risk. In the cold version, overall risk taking was similar among all three groups, even though vmPFC patients showed reduced sensitivity to trial-level variation in risk. Sensitivity to gain and loss magnitudes did not differ significantly among the groups, in either the hot or the cold CCT. These findings lend novel support to the hypothesis that the vmPFC is critical for adaptive decision making under affect-rich conditions.

We studied episodic memory and future thinking for self-relevant and other-relevant events at different levels of retrieval support, theory of mind, and delay discounting in ASD children and adolescents (ASDs). Compared to typically developing controls, ASDs produced fewer internal (episodic) but a similar number of external (semantic) details while remembering past events, imagining future events, and imagining future events happening to others, indicating a general impairment of event construction. This deficit was driven by group differences under high retrieval support, and therefore unlikely to depend on self-initiated retrieval/construction deficits. ASDs' event construction impairment related to the severity of ASD symptoms, and to theory of mind deficits. ASDs, however, showed normal delay discounting, highlighting preserved forms of future-based decision-making in ASD.

The ventromedial prefrontal cortex (vmPFC) and hippocampus have been implicated in the mental construction of scenes and events. However, little is known about their specific contributions to these cognitive functions. Boundary extension (BE) is a robust indicator of fast, automatic, and implicit scene construction. BE occurs when individuals who are viewing scenes automatically imagine what might be beyond the view, and consequently later misremember having seen a greater expanse of the scene. Patients with hippocampal damage show attenuated BE because of their scene construction impairment. In the current study, we administered BE tasks to patients with vmPFC damage, brain-damaged control patients, and healthy control participants. We also contrasted the performance of these patients to the previously-published data from patients with hippocampal lesions (Mullally, Intraub, & Maguire, 2012). We found that vmPFC-damaged patients showed reduced BE compared to brain-damaged and healthy controls. Indeed, BE attenuation was similar following vmPFC or hippocampal damage. Notably, however, whereas hippocampal damage seems to particularly impair the spatial coherence of scenes, vmPFC damage leads to a difficulty constructing scenes in a broader sense, with the prediction of what should be in a scene, and the monitoring or integration of the scene elements being particularly compromised. We conclude that vmPFC and hippocampus play important and complementary roles in scene construction.

The capacity to distinguish between intentional and unintentional actions is a crucial aspect of moral competence. Therefore, the processes shaping intentionality attribution, as well as their dysfunction, are object of intense inquiry. The 'Knobe effect' refers to the intriguing finding that people are more likely to judge as intentional actions leading to negative as opposed to positive side effects, which has been attributed to the emotional response elicited by negative (vs. positive) outcomes. Whether and how emotion drives the Knobe effect, however, is currently debated. Here, individuals with low (LA) and high (HA) levels of alexithymia, a personality trait characterized by difficulties in emotional processing, judged the intentionality of actions with side effects that varied in valence (positive/negative) and salience (low/high), while their subjective emotional response and skin conductance level were assessed. LA individuals attributed more intentionality to actions leading to negative (vs. positive) side effects, and to high (vs. low) salience side effects, and this related to their subjective emotional response to negative side effects. In the context of a generally reduced physiological activation to emotional stimuli, HA (compared to LA) individuals attributed less intentionality to actions leading to negative side effects, especially those with low salience, showing a reduced Knobe effect, which was accompanied by a reduced subjective emotional response to negative side effects. These results confirm the crucial role of emotion on intentionality attribution. Moreover, they contribute to qualifying the emotional processing difficulties associated with alexithymia, and their impact on moral cognition.

Mind-wandering, the mind’s capacity to stray from external events and generate task-unrelated thought, has been associated with activity in the brain default network. To date, little is understood about the contribution of individual nodes of this network to mind-wandering. Here, we investigated the role of medial prefrontal cortex (mPFC) in mind-wandering, by perturbing this region with transcranial direct current stimulation (tDCS). Young healthy participants performed a choice reaction time task both before and after receiving cathodal tDCS over mPFC, and had their thoughts periodically sampled. We found that tDCS over mPFC - but not occipital or sham tDCS - decreased the propensity to mind-wander. The tDCS-induced reduction in mind-wandering occurred in men, but not in women, and was accompanied by a change in the content of task-unrelated though, which became more related to other people (as opposed to the self) following tDCS. These findings indicate that mPFC is crucial for mind-wandering, possibly by helping construction of self-relevant scenarios capable to divert attention inward, away from perceptual reality. Gender-related differences in tDCS-induced changes suggest that mPFC controls mind-wandering differently in men and women, which may depend on differences in the structural and functional organization of distributed brain networks governing mind-wandering, including mPFC.

Disgust for contaminating objects (core disgust), immoral behaviors (moral disgust) and unsavory others (interpersonal disgust), have been assumed to be closely related. It is not clear, however, whether different forms of disgust are mediated by overlapping or specific neural substrates. We report that 10 patients with damage to the ventromedial prefrontal cortex (vmPFC) avoided behaviors that normally elicit interpersonal disgust (e.g. using the scarf of a busker) less frequently than healthy and brain-damaged controls, whereas they avoided core and moral disgust elicitors at normal rates. These results indicate that different forms of disgust are dissociated neurally. We propose that the vmPFC is causally (and selectively) involved in mediating interpersonal disgust, shaping patterns of social avoidance and approach.

The development of subjective recollection was investigated in participants aged 6–18 years. In Experiment 1 (N = 90), age-related improvements were found in understanding of the subjective experience of recollection, although robust levels of understanding were observed even in the youngest group. In Experiment 2 (N = 100), age-related differences were found in subjective recollection during a memory task, suggesting development not only in the ability to reflect on memory states, but also in the informational basis of subjective recollection. Lower understanding of memory states was associated with increased propensity to claim recollection. These results indicate that subjective recollection develops considerably during childhood and suggest that the development of metamemory supports this capacity.

Choices are often intertemporal, requiring tradeoff of short-term and long-term outcomes. In such contexts, humans may prefer small rewards delivered immediately to larger rewards delivered after a delay, reflecting temporal discounting (TD) of delayed outcomes. The medial orbitofrontal cortex (mOFC) is consistently activated during intertemporal choice, yet its role remains unclear. Here, patients with lesions in the mOFC (mOFC patients), control patients with lesions outside the frontal lobe, and healthy individuals chose hypothetically between small-immediate and larger-delayed rewards. The type of reward varied across three TD tasks, including both primary (food) and secondary (money and discount vouchers) rewards. We found that damage to mOFC increased significantly the preference for small-immediate over larger-delayed rewards, resulting in steeper TD of future rewards in mOFC patients compared with the control groups. This held for both primary and secondary rewards. All participants, including mOFC patients, were more willing to wait for delayed money and discount vouchers than for delayed food, suggesting that mOFC patients' (impatient) choices were not due merely to poor motor impulse control or consideration of the goods at stake. These findings provide the first evidence in humans that mOFC is necessary for valuation and preference of delayed rewards for intertemporal choice.

The ability to navigate in a familiar environment depends on both an intact mental representation of allocentric spatial information and the integrity of systems supporting complementary egocentric representations. Although the hippocampus has been implicated in learning new allocentric spatial information, converging evidence suggests that the posterior parietal cortex (PPC) might support egocentric representations. To date, however, few studies have examined long-standing egocentric representations of environments learned long ago. Here we tested 7 patients with focal lesions in PPC and 12 normal controls in remote spatial memory tasks, including 2 tasks reportedly reliant on allocentric representations (distance and proximity judgments) and 2 tasks reportedly reliant on egocentric representations (landmark sequencing and route navigation; see Rosenbaum, Ziegler, Winocur, Grady, & Moscovitch, 2004). Patients were unimpaired in distance and proximity judgments. In contrast, they all failed in route navigation, and left-lesioned patients also showed marginally impaired performance in landmark sequencing. Patients' subjective experience associated with navigation was impoverished and disembodied compared with that of the controls. These results suggest that PPC is crucial for accessing remote spatial memories within an egocentric reference frame that enables both navigation and reexperiencing. Additionally, PPC was found to be necessary to implement specific aspects of allocentric navigation with high demands on spontaneous retrieval.

Memory for context is known to rely on episodic binding and strategic retrieval processes. It is unclear, however, whether memory for different contextual features taps the same cognitive and neural mechanisms. Here, the authors compare memory for a perceptual feature (i.e., the format in which an item had been presented) and for a semantic feature (i.e., the concept with which an item had been paired) in 13 patients with lesions in ventromedial prefrontal cortex, including patients with and without confabulation, and 13 healthy controls. Participants studied picture-word pairs and received an old-new recognition test that included intact pairs, rearranged pairs, format pairs (studied pairs in which the picture-word format of each item was switched), old-new pairs, and new-new pairs. Hit rates for intact pairs were similar for all participant groups. Compared with controls, patients, especially those with confabulation, had higher false-alarm rates for format pairs but comparable false-alarm rates for rearranged pairs. The authors propose that distinct monitoring processes are engaged during retrieval of perceptual and semantic context, with only the former crucially dependent on ventromedial prefrontal cortex.

Although neuroimaging and human lesion studies agree that the medial parietal region plays a critical role in episodic memory, many neuroimaging studies have also implicated lateral parietal cortex, leading some researchers to suggest that the lateral region plays a heretofore underappreciated role in episodic memory. Because there are very few extant lesion data on this matter, we examined memory in six cases of focal lateral parietal damage, using both clinical and experimental measures, in which we distinguished between recollection and familiarity. The patients did not have amnesia, but they did show evidence of disrupted recollection on an anterograde memory task. Although the exact mechanisms remain to be elucidated, lateral parietal damage appears to impair some aspects of episodic memory.

Recent neuroimaging studies have implicated the posterior parietal cortex in episodic memory retrieval, but there is uncertainty about its specific role. Research in the attentional domain has shown that superior parietal lobe (SPL) regions along the intraparietal sulcus are implicated in the voluntary orienting of attention to relevant aspects of the environment, whereas inferior parietal lobe (IPL) regions at the temporo-parietal junction mediate the automatic allocation of attention to task-relevant information. Here we propose that the SPL and the IPL play conceptually similar roles in episodic memory retrieval. We hypothesize that the SPL allocates top-down attention to memory retrieval, whereas the IPL mediates the automatic, bottom-up attentional capture by retrieved memory contents. By reviewing the existing fMRI literature, we show that the posterior intraparietal sulcus of SPL is consistently active when the need for top-down assistance to memory retrieval is supposedly maximal, e.g., for memories retrieved with low vs. high confidence, for familiar vs. recollected memories, for recognition of high vs. low frequency words. On the other hand, the supramarginal gyrus of IPL is consistently active when the attentional capture by memory contents is supposedly maximal, i.e., for strong vs. weak memories, for vividly recollected vs. familiar memories, for memories retrieved with high vs. low confidence. We introduce a model of episodic memory retrieval that characterizes contributions of posterior parietal cortex.

A patient with ventromedial prefrontal damage, LG, is described who had a severe difficulty in wayfinding in his home town, despite intact knowledge for landmarks and routes in town. Although able to recall his spatial goals, LG often headed to familiar, "attractor" locations while navigating, losing his way in the process. Both a laboratory and an ecological study showed that spatial navigation improved when the patient was periodically reminded of, or asked to recall, the goal destination along his route. It is suggested that the ventromedial prefrontal cortex is necessary to maintain actively the goal destination in working memory, for use in navigation.

During intertemporal choice, humans tend to prefer small-sooner rewards over larger-delayed rewards, reflecting temporal discounting (TD) of delayed outcomes. Functional neuroimaging (fMRI) evidence has implicated the insular cortex in time-sensitive decisions, yet it is not clear whether activity in this brain region is crucial for, or merely associated with, TD behavior. Here, patients with damage to the insula (Insular patients), control patients with lesions outside the insula, and healthy individuals chose between smaller-sooner and larger-later monetary rewards. Insular patients were less sensitive to sooner rewards than were the control groups, exhibiting reduced TD. A Voxel-based Lesion-Symptom Mapping (VLSM) analysis confirmed a statistically significant association between insular damage and reduced TD. These results indicate that the insular cortex is crucial for intertemporal choice. We suggest that he insula may be necessary to anticipate the bodily/emotional effects of receiving rewards at different delays, influencing the computation of their incentive value. Devoid of such input, insular patients’ choices would be governed by a heuristic of quantity, allowing patients to wait for larger options.

There is increasing interest in uncovering the cognitive and neural bases of episodic future thinking (EFT), the ability to imagine events relevant to one's own future. Recent functional neuroimaging evidence shows that the ventromedial prefrontal cortex (vmPFC) is engaged during EFT. However, vmPFC is also activated during imagination of fictitious, atemporal experiences. Therefore, its role in EFT is currently unclear. To test (1) whether vmPFC is critical for EFT, and (2) whether it supports EFT specifically, or, rather, construction of any complex experience, patients with focal lesions to vmPFC (vmPFC patients), control patients with lesions not involving vmPFC, and healthy controls were asked to imagine personal future experiences and fictitious experiences. Compared to the control groups, vmPFC patients were impaired at imagining both future and fictitious experiences, indicating a general deficit in constructing novel experiences. Unlike the control groups, however, vmPFC patients had more difficulties in imagining future compared to fictitious experiences. Exploratory correlation analyses showed that general construction deficits correlated with lesion volume in BA 11, whereas specific EFT deficits correlated with lesion volume in BA 32 and BA 10. Together, these findings indicate that vmPFC is crucial for EFT. We propose, however, that different vmPFC subregions may support different component processes of EFT: the most ventral part, BA 11, may underlie core constructive processes needed to imagine any complex experience (e.g., scene construction), whereas BA 10 and BA 32 may mediate simulation of those specific experiences that likely await us in the future.

Accumulating evidence suggests that humans process time and space in similar veins. Humans represent time along a spatial continuum, and perception of temporal durations can be altered through manipulations of spatial attention by prismatic adaptation (PA). Here, we investigated whether PA-induced manipulations of spatial attention can also influence more conceptual aspects of time, such as humans’ ability to travel mentally back and forward in time (mental time travel, MTT). Before and after leftward- and rightward-PA, participants projected themselves in the past, present or future time (i.e., self-projection), and, for each condition, determined whether a series of events were located in the past or the future with respect to that specific self-location in time (i.e., self-reference). The results demonstrated that leftward and rightward shifts of spatial attention facilitated recognition of past and future events, respectively. These findings suggest that spatial attention affects the temporal processing of the human self.

Different access modes to information stored in long-term memory can lead to different distributions of errors in classification tasks. We have designed a famous faces memory classification task that allows for the extraction of a measure of metric content, an index of the relevance of semantic cues for classification performance. High levels of metric content are indicative of a relatively preferred semantic access mode, while low levels, and similar correct performance, suggest a preferential episodic access mode. Compared with normal controls, the metric content index was increased in patients with Alzheimer's disease (AD), decreased in patients with herpes simplex encephalitis, and unvaried in patients with insult in the prefrontal cortex. Moreover, the metric content index was found to correlate with a measure of the severity of dementia in patients with AD, and to track the progression of the disease. These results underline the role of the medial-temporal lobes and of the temporal cortex, respectively, for the episodic and semantic routes to memory retrieval. Moreover, they confirm the reliability of information theoretic measures for characterizing the structure of the surviving memory representations in memory-impaired patient populations.

PRIMARY OBJECTIVE: An impairment of the central executive system (CES) of working memory (WM) is a common consequence of traumatic brain injury (TBI), and may also explain deficits in divided attention, long-term memory and executive functions. Here we investigated the efficacy of a rehabilitative program (working memory training: WMT) targeting the CES in improving WM and other cognitive functions dependent on this system. METHODS AND PROCEDURES: Nine TBI patients with severe WM deficits underwent the WMT (experimental training). The WMT was preceded by a general stimulation training (GST; control training). Patients' cognitive performance was evaluated at the admission, after the GST and at the end of the WMT. MAIN OUTCOMES AND RESULTS: Whereas the GST had no effect on patients' performance, after the WMT patients improved in all the cognitive functions dependent on the CES, but not in those functions not thought to tap this system. Importantly, a beneficial WMT effect was found on patients' everyday life functioning. CONCLUSIONS: The results support the efficacy of the WMT in recovering CES impairments.

Confabulating patients claim to remember events that had not actually happened, suggesting a vivid subjective experience of false memories. The present study was aimed at examining the nature of subjective experience of retrieval in confabulators and its relation to the objective ability to recollect qualitative aspects of the original episode. In Experiment 1, 5 confabulators, 7 non-confabulating patients, and 12 control subjects studied words under shallow and deep encoding conditions and underwent a Remember (R)/Know (K) recognition task [Tulving, E. (1985). Memory and consciousness. Canadian Psychology, 26, 1-12]. For recognized words, they additionally indicated two qualitative features of the encoding context. Whereas subjective (i.e. R responses) and objective (i.e. source) measures of recollection were associated in normal controls and non-confabulating patients, they were dissociated in confabulators. In Experiment 2, participants explained the content of their R responses. We found that confabulators' recollections mainly included autobiographical information related to test items, but not to the study encounter. We conclude that remembering states in confabulators may be linked to a deficit in inhibiting irrelevant memories triggered by test items during retrieval attempts.

We explored the extent to which confabulators are susceptible to false recall and false recognition, and whether false recognition is reduced when memory for studied items is experimentally enhanced. Five confabulating patients, nine non-confabulating amnesics--including patients with (F amnesics) and without frontal-lobe dysfunction (NF amnesics)--and 14 control subjects underwent the DRM paradigm [Roediger, H. L., & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory and Cognition, 21, 803-814.] in two experimental conditions. In both conditions participants studied eight lists of semantic associates, and free recall was tested after the presentation of each list. In the Standard condition recognition was tested after the presentation of all the lists, whereas in the Proximal condition patients were administered a six-item recognition task after the presentation of each list. Participants also provided remember or know judgements, and described the content of their recollections. All groups of patients recalled a lower proportion of targets and critical lures than did control subjects, but confabulators recalled more words unrelated to the studied lists than did NF amnesics and controls. All groups of participants improved true recognition across conditions. However, whereas normal controls suppressed false recognition to critical lures in the Proximal compared to the Standard condition, and non-confabulating amnesics showed comparable gist-based false recognition, confabulators showed increased levels of false recognition to critical lures across conditions. Furthermore, NF amnesics significantly reduced false recognition to unrelated lures in the Proximal compared to the Standard condition, whereas confabulators were unable to suppress false recognition to unrelated lures across conditions. Analysis of the phenomenological experience showed that, unlike non-confabulating amnesics, confabulators characterized true and false memories with irrelevant information related to test items. Results are interpreted in light of confabulators' monitoring deficits.

The thought of one’s own death induces anxiety and threatens self-esteem. According to Terror Management Theory, to reduce this existential threat individuals typically embrace their cultural worldview, and seek for an increase in self-esteem and status by improving their productivity. Within an experimental economy setting, this paper investigates the effect of Mortality Salience (MS) on individual productivity, using for the first time a real-effort task where the economic incentive is to not perform. We investigated whether the improvement in productivity was significantly driven by self-esteem or status seeking, providing either private feedback alone or, additionally, public feedback. Always controlling for participants’ individual susceptibility to the MS induction, our results indicate that subjects generally tend to be more sensitive to in-group conformity under MS compared to a control (Music) induction condition. That is, they initially improve their performance to enhance self-esteem, but then homologate to average performance levels, consistent with the incentive not to perform. However, for a subset of less materialistic participants, with strong susceptibility to MS, performance levels constantly improved along the task.

Moral judgment involves considering not only the outcome of an action but also the intention with which it was pursued. Previous functional magnetic resonance imaging (fMRI) research has shown that integrating outcome and belief information for moral judgment relies on a brain network including temporo-parietal, precuneus, and medial prefrontal regions. Here, we investigated whether the ventromedial prefrontal cortex (vmPFC) plays a crucial role in this process. Patients with lesions in vmPFC (vmPFC patients), and brain-damaged and healthy controls considered scenarios in which the protagonist caused intentional harm (negative-outcome, negative-belief), accidental harm (negative-outcome, neutral-belief), attempted harm (neutral-outcome, negative-belief), or no harm (neutral-outcome, neutral-belief), and rated the moral permissibility of the protagonists’ behavior. All groups responded similarly to scenarios involving intentional harm and no harm. vmPFC patients, however, judged attempted harm as more permissible, and accidental harm as less permissible, than the control groups. For vmPFC patients, outcome information, rather than belief information, shaped moral judgment. The results indicate that vmPFC is necessary for integrating outcome and belief information during moral reasoning. During moral judgment vmPFC may mediate intentions’ understanding, and overriding of prepotent responses to salient outcomes. (JINS, 2012, 18, 1–10)