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When warm thermal stimulators are placed on the ring and index fingers of one hand, and a neutraltemperature\ud stimulator on the middle finger, all three fingers feel warm. This illusion is known as\ud thermal referral (TR). On one interpretation, the heterogenous thermal signals are overridden by\ud homogenous tactile signals. This cross-modal thermo-tactile interaction could reflect a process of object\ud recognition, based on the prior that many objects are thermally homogenous. Interestingly, the illusion\ud was reported to disappear when the middle digit was lifted off the thermal stimulator, suggesting that\ud tactile stimulation is necessary. However, no study has investigated whether purely thermal stimulation\ud might induce TR, without any tactile object to which temperature can be attributed. We used radiant\ud thermal stimulation to deliver purely thermal stimuli, which either were or were not accompanied by\ud simultaneous touch. We found identical TR effects in both the original thermo-tactile condition, and in\ud a purely thermoceptive condition where no tactile object was present. Control experiments ruled out\ud explanations based on poor spatial discrimination of warm signals. Our purely thermoceptive results\ud suggest that TR could reflect low-level organization of the thermoceptive pathway, rather than a\ud cognitive intermodal modulation based on tactile object perception.

By anticipating potential rewards, external cues can guide behavior to achieve a goal. Whether the conscious elaboration of these cues is necessary to elicit cue-guided choices is still unknown. The goal of the present study is to test whether the subliminal presentation of a visual cue previously paired with a reward is sufficient to bias responses that can lead to the same or a similar reward. To this aim, three experiments compared the subliminal and supraliminal presentation of reward-associated cues during a Pavlovian-to-Instrumental Transfer task. In line with previous evidence, results showed that the supraliminal presentation of reward-associated Pavlovian cues biased participant’s choice towards motivationally similar rewards (general transfer) as well as towards rewards sharing the precise sensory-specific properties of the cue (outcome-specific transfer). In striking contrast, subliminal cues biased choice only towards motivationally similar rewards (general transfer). Taken together, these findings suggest that cue-guided choices are modulated by the level of perceptual threshold (i.e., subliminal vs supraliminal) of reward-associated cues. Although conscious elaboration of the cue is necessary to guide choice towards a specific reward, subliminal processing is still sufficient to push towards choices sharing the motivational properties of the cue. Implications for everyday life, clinical conditions, and theoretical accounts of cue-guided choices are discussed.

The role of the ventromedial prefrontal cortex (vmPFC) in human pavlovian threat conditioning has been relegated largely to the extinction or reversal of previously acquired stimulus–outcome associations. However, recent neuroimaging evidence questions this view by also showing activity in the vmPFC during threat acquisition. Here we investigate the casual role of vmPFC in the acquisition of pavlovian threat conditioning by assessing skin conductance response (SCR) and declarative memory of stimulus–outcome contingencies during a differential pavlovian threat-conditioning paradigm in eight patients with a bilateral vmPFC lesion, 10 with a lesion outside PFC and 10 healthy participants (each group included both females and males). Results showed that patients with vmPFC lesion failed to produce a conditioned SCR during threat acquisition, despite no evidence of compromised SCR to unconditioned stimulus or compromised declarative memory for stimulus–outcome contingencies. These results suggest that the vmPFC plays a causal role in the acquisition of new learning and not just in the extinction or reversal of previously acquired learning, as previously thought. Given the role of the vmPFC in schema-related processing and latent structure learning, the vmPFC may be required to construct a detailed representation of the task, which is needed to produce a sustained conditioned physiological response in anticipation of the unconditioned stimulus during threat acquisition.SIGNIFICANCE STATEMENTPavlovian threat conditioning is an adaptive mechanism through which organisms learn to avoid potential threats, thus increasing their chances of survival. Understanding what brain regions contribute to such a process is crucial to understand the mechanisms underlying adaptive as well as maladaptive learning, and has the potential to inform the treatment of anxiety disorders. Importantly, the role of the ventromedial prefrontal cortex (vmPFC) in the acquisition of pavlovian threat conditioning has been relegated largely to the inhibition of previously acquired learning. Here, we show that the vmPFC actually plays a causal role in the acquisition of pavlovian threat conditioning.

Summary Erasing maladaptive memories has been a challenge for years. A way to change fear memories is to target the process of reconsolidation, during which a retrieved memory transiently returns to a labile state, amenable to modification [ 1 , 2 ]. Disruption of human fear-memory reconsolidation has been classically attempted with pharmacological [ 3 ] or behavioral (e.g., extinction) [ 4 ] treatments that, however, do not clarify the underlying brain mechanism. To address this issue, in 84 healthy humans submitted to six experiments, here, we combined a differential fear conditioning paradigm with repetitive transcranial magnetic stimulation (rTMS) administered in a state-dependent manner. In a critical condition, we stimulated the dorsolateral prefrontal cortex (dlPFC) 10 min after a reminder cue that reactivated a fear memory acquired 1 day before. At testing, 24 h after rTMS, participants exhibited decreased physiological expression of fear, as shown by their skin conductance response. Similar reductions were observed when targeting the left and the right dlPFC. In contrast, no decrease was observed in participants tested immediately after dlPFC-rTMS or in participants receiving either control rTMS (i.e., active control site and sham stimulations) or dlPFC-rTMS without preceding fear-memory reactivation, thus showing both the site and time specificity and state dependency of our rTMS intervention. Expression of fear was indeed reduced only when dlPFC-rTMS was administered within the reconsolidation time window. Moreover, dlPFC-rTMS prevented subsequent return of fear after extinction training. These findings highlight the causal role of dlPFC in fear-memory reconsolidation and suggest that rTMS can be used in humans to prevent the return of fear.

The brain constructs a functional representation of the space around the body, the so called peripersonal space (PPS), which is a sensorimotor interface used to ensure suitable motor acts. However, this sector of space is also involved in social interactions. Individuals indeed, maintain an interpersonal space (IPS) indicating how close they prefer to stand relative to others. Here, we investigated whether a change in one’s own body height representation can differently modulate action and social space. To this aim, we measured IPS and PPS in a similar way through a Reaching-distance and a Comfort-distance task, respectively, before and after participants experienced the illusion of having a tall (Experiment 1), or a short (Experiment 2), body. The illusion of having a tall body significantly reduced the IPS and enlarged PPS. On the other hand, the illusion of having a short body contracted the IPS, leaving the PPS intact. A further experiment (Experiment 3), showed that the illusory ownership for the tall or short body is a necessary condition to update the participants’ height representation. Thus, a change in body height representation was effective to reveal a dissociation in the representation of the space around the body, depending on whether this sector of space is used for programming actions, or for regulating social interactions.

Information gathered via Pavlovian and Instrumental learning can be integrated to guide behavior, in a phenomenon experimentally known as Pavlovian-to-Instrumental Transfer (PIT). In particular, in appetitive PIT, a reward-associated cue is able to enhance the instrumental response previously associated with the same (outcome-specific PIT), or a similar (general PIT), reward. The PIT effect is increasingly investigated for its numerous implications in clinical contexts as well as daily life situations. Nevertheless, the precise mechanism behind it is not yet clear. The relation between the PIT effect and high-level cognitive abilities - like working memory - is still unknown, but potentially relevant to unveil its functioning. The present study aims to examine the precise relationship between individual differences in working memory and the two forms of PIT effect, namely outcome-specific and general. For this purpose, 100 participants underwent a classical PIT paradigm. Results showed a relationship between individual working memory and outcome-specific PIT, but not general PIT. Importantly, the role of working memory was not related to the acquisition of the learning contingencies, but rather linked to an imbalance between congruent and incongruent choices. The results are discussed in terms of the adaptive and maladaptive implications for human behavior.

In recent years, there has been a dramatic increase in research examining interpersonal space, i.e., the sector of space immediately around the body in which we interact with other people. These studies have consistently revealed impairments of interpersonal space regulation in psychopathological disorders characterized by social disability, such as autism, schizophrenia and social anxiety. The primary goal of this review is to discuss several key points that have emerged in research on interpersonal space regulation in autism spectrum disorders. Particularly, we review recent behavioral evidence revealing that individuals with autism prefer abnormally larger or shorter interpersonal distance than healthy controls, indicating a deficit in regulating the size of interpersonal space (permeability). Then, we focus on how individuals with autism fail to modify their interpersonal space following a brief cooperative interaction with an unfamiliar adult, suggesting a deficit in adapting interpersonal space to the social context (plasticity). Moreover, we discuss evidence indicating that space regulation deficits primarily affect interpersonal (i.e., social), but not peripersonal (i.e., action), space in autism. Finally, we take into consideration the variables influencing interpersonal space plasticity such as person's perspective and severity of social impairment as well as its neural underpinnings. These findings may provide a critical contribution to understanding of the functional mechanisms underlying interpersonal space regulation and its rehabilitation in autism spectrum disorders.

The space around the body, i.e., peripersonal space (PPS), is conceived as a multisensory-motor interface between body and environment. PPS is represented by frontoparietal neurons integrating tactile, visual, and auditory stimuli occurring near the body [1-7]. PPS is plastic, because it extends by using a tool to reach far objects [8-10]. Although interactions with others occur within PPS, little is known about how social environment modulates it. Here, we show that presence and interaction with others shape PPS representation. Participants performed a tactile detection task on their face while concurrent task-irrelevant sounds approached toward or receded from their face. Because a sound affects touch when occurring within PPS [6, 10-12], we calculated the critical distance where sounds speeded up tactile reaction time as a proxy of PPS boundaries. Experiment 1 shows that PPS boundaries shrink when subjects face another individual, as compared to a mannequin, placed in far space. Experiment 2 and 3 show that, after playing an economic game with another person, PPS boundaries between self and other merge, but only if the other behaved cooperatively. These results reveal that PPS representation is sensitive to social modulation, showing a link between low-level sensorimotor processing and high-level social cognition. © 2013 Elsevier Ltd.

The ability to infer deceptive intents from nonverbal behavior is critical for social interactions. By combining single-pulse and repetitive transcranial magnetic stimulation (TMS) in healthy humans, we provide both correlational and causative evidence that action simulation is actively involved in the ability to recognize deceptive body movements. We recorded motor-evoked potentials during a faked-action discrimination (FAD) task: participants watched videos of actors lifting a cube and judged whether the actors were trying to deceive them concerning the real weight of the cube. Seeing faked actions facilitated the observers' motor system more than truthful actions in a body-part-specific manner, suggesting that motor resonance was sensitive to deceptive movements. Furthermore, we found that TMS virtual lesion to the anterior node of the action observation network, namely the left inferior frontal cortex (IFC), reduced perceptual sensitivity in the FAD task. In contrast, no change in FAD task performance was found after virtual lesions to the left temporoparietal junction (control site). Moreover, virtual lesion to the IFC failed to affect performance in a difficulty-matched spatial-control task that did not require processing of spatiotemporal (acceleration) and configurational (limb displacement) features of seen actions, which are critical to detecting deceptive intent in the actions of others. These findings indicate that the human IFC is critical for recognizing deceptive body movements and suggest that FAD relies on the simulation of subtle changes in action kinematics within the motor system.

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.

Observing a face with averted eyes results in a reflexive shift of attention to the gazed-at location. Here we present results that show that this effect is weaker in males than in females (Experiment 1). This result is predicted by the ‘extreme male brain’ theory of autism (Baron-Cohen, 2003), which suggests that males in the normal population should display more autism-like traits than females (e.g., poor joint attention). Indeed, participants′ scores on the Autism-Spectrum Quotient (Baron-Cohen, Wheelwright, Stott, Bolton, & Goodyear, 2001) negatively correlated with cueing magnitude. Furthermore, exogenous orienting did not differ between the sexes in two peripheral cueing experiments (Experiments 2a and 2b). However, a final experiment showed that using non-predictive arrows instead of eyes as a central cue also revealed a large gender difference. This demonstrates that reduced orienting from central cues in males generalizes beyond gaze cues. These results show that while peripheral cueing is equivalent in the male and female brains, the attention systems of the two sexes treat noninformative symbolic cues very differently.

Research based on event-related potential (ERP) reported mediofrontal negativities following unexpected negative feedback or performance error. Some authors proposed that these signals reflect reward prediction error for worse than expected outcomes, while others suggested that mediofrontal negativities express medial prefrontal cortex coding for unexpected non-occurrence of a predicted outcome, whether worse or better than expected. Many studies found mediofrontal negativities coding for unexpected negative outcomes; however, few studies found them after unexpected positive outcomes. The present study investigated ERP and skin conductance response (SCR) to the unexpected omission of electric shocks during Pavlovian aversive conditioning. To manipulate expectancies, participants were presented with visual stimuli paired with electric shock on either 80% (CS+1) or 20% (CS+2) of trials. SCR analysis confirmed higher shock-delivery expectancy for CS+1, relative to CS+2. ERP analysis evidenced a stronger negative frontocentral ERP component after unexpected, relative to expected, shock-omission. Methodological and theoretical implications are discussed.

Growing evidence suggests that the ability to control behavior is enhanced in contexts in which errors are more frequent. Here we investigated whether pairing desirable food with errors could decrease impulsive choice during hypothetical temporal decisions about food. To this end, healthy women performed a Stop-signal task in which one food cue predicted high-error rate, and another food cue predicted low-error rate. Afterwards, we measured participants’ intertemporal preferences during decisions between smaller-immediate and larger-delayed amounts of food. We expected reduced sensitivity to smaller-immediate amounts of food associated with high-error rate. Moreover, taking into account that deprivational states affect sensitivity for food, we controlled for participants’ hunger. Results showed that pairing food with high-error likelihood decreased temporal discounting. This effect was modulated by hunger, indicating that, the lower the hunger level, the more participants showed reduced impulsive preference for the food previously associated with a high number of errors as compared with the other food. These findings reveal that errors, which are motivationally salient events that recruit cognitive control and drive avoidance learning against error-prone behavior, are effective in reducing impulsive choice for edible outcomes.

Alexithymia refers to difficulties in recognizing one's own emotions, but difficulties have also been found in the recognition of others' emotions, particularly when the task is not easy. Previous research has demonstrated that, in order to understand other peoples' feelings, observers remap the observed emotion onto their own sensory systems. The aim of the present study was to investigate the ability of high and low alexithymic subjects to remap the emotional expressions of others onto their own somatosensory systems using an indirect task. We used the emotional Visual Remapping of Touch (eVRT) paradigm, in which seeing a face being touched improves detection of near-threshold tactile stimulation concurrently delivered to one's own face. In eVRT, subjects performance is influenced by the emotional content of the stimuli, while they were required to distinguish between unilateral or bilateral tactile stimulation on their own cheeks. The results show that tactile perception was enhanced when viewing touch on a fearful face compared with viewing touch on other expressions in low but not in high alexithymic participants. A negative correlation between TAS-20 alexithymia subscale ("difficulty in identify feelings") and the magnitude of the eVRT effect was also found. Conversely, arousal and valence ratings of emotional faces did not vary as a function of the degree of alexithymia. The results provide evidence that alexithymia is associated with difficulties in remapping seen emotions, particularly fear, onto one's own sensory system. This impairment could be due to an inability to modulate somatosensory system activity according to the observed emotional expression.

Purpose Although neuropsychological impairments are common in Multiple Sclerosis (MS), the manifestation of cognitive deficits may vary greatly across MS patients. Here, we explored the influence of cognitive reserve proxy indices (education and occupation) and perceived fatigue on cognitive performance. Methods Fifty relapsing-remitting MS patients were evaluated. Cognitive performance was measured using the Paced Auditory Serial Addition Test (PASAT), in which information processing speed can be manipulated by varying the presentation speed of stimuli. Results MS patients with low education performed worse than healthy controls at faster PASAT speeds. By contrast, no difference was observed between MS patients with high education and matched healthy controls, regardless of PASAT speed. Moreover, we found that neither occupational attainment nor perceived fatigue has an influence on MS patients' cognitive performance. Conclusion These findings provide evidence that higher education could be protective against MS-associated cognitive deficits and that high speed PASAT versions are more suitable for identifying compensatory capacities compared to low speed PASAT versions.

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)

The present study investigated whether the error-related negativity, an electrophysiological marker for performance monitoring, reflects (1) the expectancy of errors, or (2) the significance of errors for the current task goal. In the first case, a larger error-related negativity is predicted for less expected errors, whereas in the second case, a larger error-related negativity is predicted for errors with greater significance. To test these predictions, we varied flanker size in a flanker task. With large flankers, more errors occurred by executing the response associated with the flankers (flanker errors) leading to a greater expectancy of flanker errors. As revealed by a multinomial model, these additional flanker errors represented highly significant attention errors, leading to an increased error significance. The error-related negativity was larger for flanker errors with large flankers, which supports the error significance account.

Fundamental to adaptive behaviour is the ability to select environmental objects that best satisfy current needs and preferences. Here we investigated whether temporary changes in food preference influence visual selective attention. To this end, we exploited the fact that when a food is eaten to satiety its motivational value and perceived pleasantness decrease relative to other foods not eaten in the meal, an effect termed sensory-specific satiety. A total of 26 hungry participants were fed until sated with one of two palatable foods. Before and after selective satiation, participants rated the pleasantness of the two foods and then viewed the same as stimuli on a computer screen while attention was assessed by a visual probe task. Results showed that the attentional bias for the food eaten decreased markedly from pre- to postsatiety, along with the subjective pleasantness for that food. By contrast, subjective pleasantness and attentional bias for the food not eaten did not show any such decrease. These findings suggest that the allocation of visual selective attention is flexibly and rapidly adjusted to reflect temporary shift in relative preference for different foods.

We report two studies aimed at investigating the effects of distinct negative emotions on pairwise economic interactions. In the ultimatum game, a proposer offers a division of a sum of money to a responder who decides whether to accept the split, or reject and leave both players with nothing. In Experiment 1, we investigated whether induced disgust, as compared to sadness and neutral emotion, specifically influences responders' decisions to reject unfair proposals. In Experiment 2, we assessed whether the effects of disgust were selectively related to social contexts by contrasting interactions with a human partner with those involving a computer. Results showed that relative to being in a sad or neutral mood, induced feelings of disgust significantly increased rejection rates of unfair offers. Moreover, we found that when the partner was not responsible for the fairness violation, such as in the computer-offer condition, the disgust induction failed to affect participants' choices. We conclude by focusing on the hypothesis that disgust and social norm violations may share common computational components, both at a psychological and a neural level.

Converging evidence suggests that emotion processing mediated by ventromedial prefrontal cortex (vmPFC) is necessary to prevent personal moral violations. In moral dilemmas, for example, patients with lesions in vmPFC are more willing than normal controls to approve harmful actions that maximize good consequences (e.g., utilitarian moral judgments). Yet, none of the existing studies has measured subjects' emotional responses while they considered moral dilemmas. Therefore, a direct link between emotion processing and moral judgment is still lacking. Here, vmPFC patients and control participants considered moral dilemmas while skin conductance response (SCR) was measured as a somatic index of affective state. Replicating previous evidence, vmPFC patients approved more personal moral violations than did controls. Critically, we found that, unlike control participants, vmPFC patients failed to generate SCRs before endorsing personal moral violations. In addition, such anticipatory SCRs correlated negatively with the frequency of utilitarian judgments in normal participants. These findings provide direct support to the hypothesis that the vmPFC promotes moral behavior by mediating the anticipation of the emotional consequences of personal moral violations.

Lesion and imaging studies have implicated the ventromedial prefrontal cortex (vmPFC) in economic decisions and social interactions, yet its exact functions remain unclear. Here, we investigated the hypothesis that the vmPFC represents the subjective value or desirability of future outcomes during social decision-making. Both vmPFC-damaged patients and control participants acted as the responder in a single-round ultimatum game. To test outcome valuation, we contrasted concrete, immediately available gains with abstract, future ones. To test social valuation, we contrasted interactions with a human partner and those involving a computer. We found that, compared to controls, vmPFC patients substantially reduced their acceptance rate of unfair offers from a human partner, but only when financial gains were presented as abstract amounts to be received later. When the gains were visible and readily available, the vmPFC patients' acceptance of unfair offers was normal. Furthermore, unlike controls, vmPFC patients did not distinguish between unfair offers from a human agent and those from a computerized opponent. We conclude that the vmPFC encodes the expected value of abstract, future goals in a common neural currency that takes into account both reward and social signals in order to optimize economic decision-making.

Both theoretical and empirical studies suggest that numerical processing is intimately linked to representations of goal-directed hand actions. Further evidence for this possibility is provided here by the results of two experiments, both of which revealed a powerful influence of numerical magnitude on the selection of hand grasping movements. Human participants performed either power or precision grip responses based on the semantic properties (e.g., parity) of visual Arabic numerals, in Experiment 1, or depending on their surface characteristics (e.g., colour), in Experiment 2. In both the experiments, it was found that small numerical values facilitated precision grip (commonly used to grasp small objects), while large numerical value potentiated power grip (commonly used to grasp large objects). These findings reveal that perceiving numbers can automatically prime grasping gestures, in a similar manner to viewing physical objects. This result is coherent with the view that processing of symbolic (numerical) and physical quantitative information converges onto a shared magnitude system representing the coordinates of action.

Experimental psychology often studies perception analytically, reducing its focus to minimal sensory units, such as\ud thresholds or just noticeable differences in a single stimulus. Here, in contrast, we examine a synthetic aspect: how\ud multiple inputs to a sensory system are aggregated into an overall percept. Participants in three experiments judged the\ud total stimulus intensity for simultaneous electrical shocks to two digits. We tested whether the integration of component\ud somatosensory stimuli into a total percept occurs automatically, or rather depends on the ability to consciously\ud perceive discrepancy among components (Experiment 1), whether the discrepancy among these components influences\ud sensitivity or/and perceptual bias in judging totals (Experiment 2), and whether the salience of each individual component\ud stimulus affects perception of total intensity (Experiment 3). Perceptual aggregation of two simultaneous component\ud events occurred both when participants could perceptually discriminate the two intensities, and also when they could\ud not. Further, the actual discrepancy between the stimuli modulated both participants’ sensitivity and perceptual bias:\ud increasing discrepancies produced a systematic and progressive overestimation of total intensity. The degree of this\ud bias depended primarily on the salience of the stronger stimulus in the pair. Overall, our results suggest that important\ud nonlinear mechanisms contribute to sensory aggregation. The mind aggregates component inputs into a coherent and\ud synthetic perceptual experience in a salience-weighted fashion that is not based on simple summation of inputs.