The question of how we make, and how we should make judgments and decisions has occupied thinkers for many centuries. This thesis has the aim to add new evidences to clarify the brain’s mechanisms for decisions. The cognitive and the emotional processes of social actions and decisions are investigated with the aim to understand which brain areas are mostly involved. Four experimental studies are presented. A specific kind of population is involved in the first study (as well as in study III) concerning patients with lesion of ventromedial prefrontal cortex (vmPFC). This region is collocated in the ventral surface of frontal lobe, and it seems have an important role in social and moral decision in forecasting the negative emotional consequences of choice. In study I, it is examined whether emotions, specifically social emotions subserved by the vmPFC, affect people’s willingness to trust others. In study II is observed how incidental emotions could encourage trusting behaviour, especially when individuals are not aware of emotive stimulation. Study III has the aim to gather a direct psychophysiological evidence, both in healthy and neurologically impaired individuals, that emotions are crucially involved in shaping moral judgment, by preventing moral violations. Study IV explores how the moral meaning of a decision and its subsequent action can modulate the basic component of action such as sense of agency.

The general aim of the thesis was to investigate how and to what extent the characteristics of action organization are reflected in language, and how they influence language processing and understanding. Even though a huge amount of research has been devoted to the study of the motor effects of language, this issue is very debated in literature. Namely, the majority of the studies have focused on low-level motor effects such as effector-relatedness of action, whereas only a few studies have started to systematically investigate how specific aspects of action organization are encoded and reflected in language. After a review of previous studies on the relationship between language comprehension and action (chapter 1) and a critical discussion of some of them (chapter 2), the thesis is composed by three experimental chapters, each devoted to a specific aspect of action organization. Chapter 3 presents a study designed with the aim to disentangle the effective time course of the involvement of the motor system during language processing. Three kinematics experiments were designed in order to determine whether and, at which stage of motor planning and execution effector-related action verbs influence actions executed with either the same or a different effector. Results demonstrate that the goal of an action can be linguistically re-activated, producing a modulation of the motor response. In chapter 4, a second study investigates the interplay between the role of motor perspective (agent) and the organization of action in motor chains. More specifically, this kinematics study aims at deepening how goal can be translated in language, using as stimuli simple sentences composed by a pronoun (I, You, He/She) and a verb. Results showed that the perspective activated by the pronoun You reflects the motor pattern of the “agent” combined with the chain structure of the verb. These data confirm an early involvement of the motor system in language processing, suggesting that it is specifically modulated by the activation of the agent’s perspective. In chapter 5, the issue of perspective is specifically investigated, focusing on its role in language comprehension. In particular, this study aimed at determining how a specific perspective (induced for example by a personal pronoun) modulates motor behaviour during and after language processing. A classical compatibility effect (the Action-sentence compatibility effect) has been used to this aim. In three behavioural experiments the authors investigated how the ACE is modulated by taking first or third person perspective. Results from these experiments showed that the ACE effect occurs only when a first-person perspective is activated by the sentences used as stimuli. Overall, the data from this thesis contributed to disentangle several aspects of how action organization is translated in language, and then reactivated during language processing. This constitutes a new contribution to the field, adding lacking information on how specific aspects such as goal and perspective are linguistically described. In addition, these studies offer a new point of view to understand the functional implications of the involvement of the motor system during language comprehension, specifically from the point of view of our social interactions.

The ability of integrating into a unified percept sensory inputs deriving from different sensory modalities, but related to the same external event, is called multisensory integration and might represent an efficient mechanism of sensory compensation when a sensory modality is damaged by a cortical lesion. This hypothesis has been discussed in the present dissertation. Experiment 1 explored the role of superior colliculus (SC) in multisensory integration, testing patients with collicular lesions, patients with subcortical lesions not involving the SC and healthy control subjects in a multisensory task. The results revealed that patients with collicular lesions, paralleling the evidence of animal studies, demonstrated a loss of multisensory enhancement, in contrast with control subjects, providing the first lesional evidence in humans of the essential role of SC in mediating audio-visual integration. Experiment 2 investigated the role of cortex in mediating multisensory integrative effects, inducing virtual lesions by inhibitory theta-burst stimulation on temporo-parietal cortex, occipital cortex and posterior parietal cortex, demonstrating that only temporo-parietal cortex was causally involved in modulating the integration of audio-visual stimuli at the same spatial location. Given the involvement of the retino-colliculo-extrastriate pathway in mediating audio-visual integration, the functional sparing of this circuit in hemianopic patients is extremely relevant in the perspective of a multisensory-based approach to the recovery of unisensory defects. Experiment 3 demonstrated the spared functional activity of this circuit in a group of hemianopic patients, revealing the presence of implicit recognition of the fearful content of unseen visual stimuli (i.e. affective blindsight), an ability mediated by the retino-colliculo-extrastriate pathway and its connections with amygdala. Finally, Experiment 4 provided evidence that a systematic audio-visual stimulation is effective in inducing long-lasting clinical improvements in patients with visual field defect and revealed that the activity of the spared retino-colliculo-extrastriate pathway is responsible of the observed clinical amelioration, as suggested by the greater improvement observed in patients with cortical lesions limited to the occipital cortex, compared to patients with lesions extending to other cortical areas, found in tasks high demanding in terms of spatial orienting. Overall, the present results indicated that multisensory integration is mediated by the retino-colliculo-extrastriate pathway and that a systematic audio-visual stimulation, activating this spared neural circuit, is able to affect orientation towards the blind field in hemianopic patients and, therefore, might constitute an effective and innovative approach for the rehabilitation of unisensory visual impairments.

Recognizing one’s body as separate from the external world plays a crucial role in detecting external events, and thus in planning adequate reactions to them. In addition, recognizing one’s body as distinct from others’ bodies allows remapping the experiences of others onto one’s sensory system, providing improved social understanding. In line with these assumptions, two well-known multisensory mechanisms demonstrated modulations of somatosensation when viewing both one’s own and someone else’s body: the Visual Enhancement of Touch (VET) and the Visual Remapping of Touch (VRT) effects. Vision of the body, in the former, and vision of the body being touched, in the latter, enhance tactile processing. The present dissertation investigated the multisensory nature of these mechanisms and their neural bases. Further experiments compared these effects for viewing one’s own body or viewing another person’s body. These experiments showed important differences in multisensory processing for one’s own body, and for other bodies, and also highlighted interactions between VET and VRT effects. The present experimental evidence demonstrated that a multisensory representation of one’s body – underlie by a high order fronto-parietal network - sends rapid modulatory feedback to primary somatosensory cortex, thus functionally enhancing tactile processing. These effects were highly spatially-specific, and depended on current body position. In contrast, vision of another person’s body can drive mental representations able to modulate tactile perception without any spatial constraint. Finally, these modulatory effects seem sometimes to interact with high order information, such as emotional content of a face. This allows one’s somatosensory system to adequately modulate perception of external events on the body surface, as a function of its interaction with the emotional state expressed by another individual.

Il presente elaborato ha per oggetto la tematica del Sé, in particolar modo il Sé corporeo. Il primo capitolo illustrerà la cornice teorica degli studi sul riconoscimento del Sé corporeo, affrontando come avviene l’elaborazione del proprio corpo e del proprio volto rispetto alle parti corporee delle altre persone. Il secondo capitolo descriverà uno studio su soggetti sani che indaga l’eccitabilità della corteccia motoria nei processi di riconoscimento sé/altro. I risultati mostrano un incremento dell’eccitabilità corticospinale dell’emisfero destro in seguito alla presentazione di stimoli propri (mano e cellulare), a 600 e 900 ms dopo la presentazione dello stimolo, fornendo informazioni sulla specializzazione emisferica substrati neurali e sulla temporalità dei processi che sottendono all’elaborazione del sé. Il terzo capitolo indagherà il contributo del movimento nel riconoscimento del Sé corporeo in soggetti sani ed in pazienti con lesione cerebrale destra. Le evidenze mostrano come i pazienti, che avevano perso la facilitazione nell’elaborare le parti del proprio corpo statiche, presentano tale facilitazione in seguito alla presentazione di parti del proprio corpo in movimento. Il quarto capitolo si occuperà dello sviluppo del sé corporeo in bambini con sviluppo atipico, affetti da autismo, con riferimento al riconoscimento di posture emotive proprie ed altrui. Questo studio mostra come alcuni processi legati al sé possono essere preservati anche in bambini affetti da autismo. Inoltre i dati mostrano che il riconoscimento del sé corporeo è modulato dalle emozioni espresse dalle posture corporee sia in bambini con sviluppo tipico che in bambini affetti da autismo. Il quinto capitolo sarà dedicato al ruolo dei gesti nel riconoscimento del corpo proprio ed altrui. I dati di questo studio evidenziano come il contenuto comunicativo dei gesti possa facilitare l’elaborazione di parti del corpo altrui. Nella discussione generale i risultati dei diversi studi verranno considerati all’interno della loro cornice teorica. / The present study concerns the theme of the self, especially the bodily self. The first chapter will describe the theoretical framework of self-body recognition and the processing that allow us to distinguish one’s own body and face from body and face of someone else. The second chapter will investigate motor cortex excitability during self/other recognition processing in healthy subjects. The results show an increment of motor corticospinal excitability in the right hemisphere following the presentation of self stimuli (hand and phone), at 600 and 900 ms after stimulus presentation, providing evidences about neural substrates and temporal processes underlying self-body recognition. The third chapter will describe the role of the movement in self bodily recognition in healthy subjects and in patients with right brain damage. The evidences show that patients, who did not show the advantage in the implicit recognition of self static body parts , present this advantage in the implicit recognition of self dynamic body parts. The fourth chapter will focus on the development of the bodily self in children with typical development and in children with autism, with respect to the recognition of self/other emotional body postures. First, this study shows that the advantage in bodily self processing is preserved in children with autism. Second, emotional body postures modulate self and others body processing in typically developmental children as well as in children with autism. The fifth chapter will study the role of gesture in self/other bodily recognition processing, showing that the meaning of the gesture modulates the self/other processing. The processing of others’ hand is facilitated with meaningful compared to meaningless gestures. The overall significance of the results will be argued in the general discussion.

Numerosi studi mostrano che gli intervalli temporali sono rappresentati attraverso un codice spaziale che si estende da sinistra verso destra, dove gli intervalli brevi sono rappresentati a sinistra rispetto a quelli lunghi. Inoltre tale disposizione spaziale del tempo può essere influenzata dalla manipolazione dell’attenzione-spaziale. La presente tesi si inserisce nel dibattito attuale sulla relazione tra rappresentazione spaziale del tempo e attenzione-spaziale attraverso l’uso di una tecnica che modula l’attenzione-spaziale, ovvero, l’Adattamento Prismatico (AP). La prima parte è dedicata ai meccanismi sottostanti tale relazione. Abbiamo mostrato che spostando l’attenzione-spaziale con AP, verso un lato dello spazio, si ottiene una distorsione della rappresentazione di intervalli temporali, in accordo con il lato dello spostamento attenzionale. Questo avviene sia con stimoli visivi, sia con stimoli uditivi, nonostante la modalità uditiva non sia direttamente coinvolta nella procedura visuo-motoria di AP. Questo risultato ci ha suggerito che il codice spaziale utilizzato per rappresentare il tempo, è un meccanismo centrale che viene influenzato ad alti livelli della cognizione spaziale. La tesi prosegue con l’indagine delle aree corticali che mediano l’interazione spazio-tempo, attraverso metodi neuropsicologici, neurofisiologici e di neuroimmagine. In particolare abbiamo evidenziato che, le aree localizzate nell’emisfero destro, sono cruciali per l’elaborazione del tempo, mentre le aree localizzate nell’emisfero sinistro sono cruciali ai fini della procedura di AP e affinché AP abbia effetto sugli intervalli temporali. Infine, la tesi, è dedicata allo studio dei disturbi della rappresentazione spaziale del tempo. I risultati ci indicano che un deficit di attenzione-spaziale, dopo danno emisferico destro, provoca un deficit di rappresentazione spaziale del tempo, che si riflette negativamente sulla vita quotidiana dei pazienti. Particolarmente interessanti sono i risultati ottenuti mediante AP. Un trattamento con AP, efficace nel ridurre il deficit di attenzione-spaziale, riduce anche il deficit di rappresentazione spaziale del tempo, migliorando la qualità di vita dei pazienti. / Numerous studies showed that time intervals are represented via a spatial code ascending from left to right, where shorter intervals are represented to the left of longer intervals. There is also evidence that, this temporal-spatial line, can be manipulated by manipulating the spatial-attention direction. The present thesis contributes to the current debate on the relationship between spatial representation of time and spatial-attention by using a technique to modulate spatial-attention, i.e. Prismatic-Adaptation (PA). In a first part we wondered about the behavioral mechanisms of the spatial-attention and time interaction. We showed that a shift of spatial-attention toward a side of space by PA, induces a distortion of the representation of time stimuli according to the side of attentional manipulation. This is true for time stimuli presented in visual modality but also in auditory modality that is not directly involved in the visuo-motor procedure of PA. This results suggested that the spatial code used to represent time, is a very centralized representation that is affected by spatial operations at high levels of spatial cognition. We followed with the investigation of the cortical areas subtending the space-time interaction. With neuropsychological, neurophysiological and neuroimaging methods, we found that areas in the right hemisphere are selectively related to the pure processing of time, while areas in the left hemisphere are selectively related to the success of PA procedure and to the effects of PA on time. Finally, we focused on the study of the pathology of the spatial representation of time. We found that a spatial-attention deficit, following a right hemispheric stroke, induces a deficit in the spatial representation of time that reflects in patients’ daily life. Moreover we found that a PA treatment, effective in reducing the spatial-attention deficit, also reduces the spatial representation of time disorder, improving patients’ quality of life.

The relationship between emotion and cognition is a topic that raises great interest in research. Recently, a view of these two processes as interactive and mutually influencing each other has become predominant. This dissertation investigates the reciprocal influences of emotion and cognition, both at behavioral and neural level, in two specific fields, such as attention and decision-making. Experimental evidence on how emotional responses may affect perceptual and attentional processes has been reported. In addition, the impact of three factors, such as personality traits, motivational needs and social context, in modulating the influence that emotion exerts on perception and attention has been investigated. Moreover, the influence of cognition on emotional responses in decision-making has been demonstrated. The current experimental evidence showed that cognitive brain regions such as the dorsolateral prefrontal cortex are causally implicated in regulation of emotional responses and that this has an effect at both pre and post decisional stages. There are two main conclusions of this dissertation: firstly, emotion exerts a strong influence on perceptual and attentional processes but, at the same time, this influence may also be modulated by other factors internal and external to the individuals. Secondly, cognitive processes may modulate emotional prepotent responses, by serving a regulative function critical to driving and shaping human behavior in line with current goals. / La relazione tra emozione e cognizione è un argomento che ha suscitato grande interesse nella ricerca. Recentemente, una visione interattiva e di mutua influenza fra questi due processi è diventata predominante. Il presente lavoro di tesi indaga le influenze reciproche di emozione e cognizione, sia a livello comportamentale che neurale, in due specifici settori, quali l'attenzione e i processi decisionali. Nella prima parte, il lavoro presenta evidenze sperimentali di come le emozioni possano influenzare processi cognitivi come quelli percettivi ed attentivi. Allo stesso tempo aggiunge su come alcuni particolare fattori, come la personalità, le esigenze motivazionali del soggetto e il contesto sociale, possano modulare l’influenza che le emozioni esercitano sui processi cognitive in questione. Nella seconda parte é stato investigato l’influsso della cognizione sulle risposte emotive, in particolare durante i processi decisionali. I risultati degli esperimenti mostrano che regioni cerebrali cognitive, come la corteccia prefrontale dorsolaterale, sono implicate in modo causale nella regolazione e nel controllo di risposte emotive automatiche e che cio’ ha un effetto sia in fasi pre-decisionali (formazione della decisione) sia in fasi post-decisionali (cambiamento di preferenze). Due sono le principali conclusioni di questa tesi: in primo luogo, è stato mostrato che l'emozione esercita una forte influenza sui processi percettivi e attentivi, ma che, allo stesso tempo, questa influenza può essere modulata da altri fattori interni ed esterni agli individui. In secondo luogo, è stato mostrato che i processi cognitivi interagiscono con quelli emotivi svolgendo un funzione regolatrice fondamentale per guidare e plasmare il comportamento umano in linea con gli obiettivi correnti degli individui.

People are daily faced with intertemporal choice, i.e., choices differing in the timing of their consequences, frequently preferring smaller-sooner rewards over larger-delayed ones, reflecting temporal discounting of the value of future outcomes. This dissertation addresses two main goals. New evidence about the neural bases of intertemporal choice is provided. Following the disruption of either the medial orbitofrontal cortex or the insula, the willingness to wait for larger-delayed outcomes is affected in odd directions, suggesting the causal involvement of these areas in regulating the value computation of rewards available with different timings. These findings were also supported by a reported imaging study. Moreover, this dissertation provides new evidence about how temporal discounting can be modulated at a behavioral level through different manipulations, e.g., allowing individuals to think about the distant time, pairing rewards with aversive events, or changing their perceived spatial position. A relationship between intertemporal choice, moral judgements and aging is also discussed. All these findings link together to support a unitary neural model of temporal discounting according to which signals coming from several cortical (i.e., medial orbitofrontal cortex, insula) and subcortical regions (i.e., amygdala, ventral striatum) are integrated to represent the subjective value of both earlier and later rewards, under the top-down regulation of dorsolateral prefrontal cortex. The present findings also support the idea that the process of outcome evaluation is strictly related to the ability to pre-experience and envision future events through self-projection, the anticipation of visceral feelings associated with receiving rewards, and the psychological distance from rewards. Furthermore, taking into account the emotions and the state of arousal at the time of decision seems necessary to understand impulsivity associated with preferring smaller-sooner goods in place of larger-later goods.

A successful interaction with objects in the environment requires integrating information concerning object-location with the shape, dimension and position of body parts in space. The former information is coded in a multisensory representation of the space around the body, i.e. peripersonal space (PPS), whereas the latter is enabled by an online, constantly updated, action-orientated multisensory representation of the body (BR) that is critical for action. One of the critical features of these representations is that both PPS and BR are not fixed, but they dynamically change depending on different types of experience. In a series of experiment, I studied plastic properties of PPS and BR in humans. I have developed a series of methods to measure the boundaries of PPS representation (Chapter 4), to study its neural correlates (Chapter 3) and to assess BRs. These tasks have been used to study changes in PPS and BR following tool-use (Chapter 5), multisensory stimulation (Chapter 6), amputation and prosthesis implantation (Chapter 7) or social interaction (Chapter 8). I found that changes in the function (tool-use) and the structure (amputation and prosthesis implantation) of the physical body elongate or shrink both PPS and BR. Social context and social interaction also shape PPS representation. Such high degree of plasticity suggests that our sense of body in space is not given at once, but it is constantly constructed and adapted through experience. / Allo scopo di interagire con oggetti presenti nell’ambiente esterno è necessario integrare le informazioni sulla posizione degli oggetti nello spazio con informazioni riguardanti la forma, dimensione e posizione delle singole parti del corpo rispetto all’oggetto stesso. Due diverse rappresentazioni supportano la codifica di tali informazioni: da una parte, la rappresentazione dello Spazio Peripersonale, una rappresentazione multisensoriale dello spazio intorno al corpo, e dall’altra una rappresentazione multisensoriale del corpo, costantemente aggiornata e orientata all’azione. Una caratteristica critica di queste rappresentazioni è rappresentata dalle loro proprietà plastiche, cioè dalla possibilità di modificarsi in seguito a diversi tipi di esperienza. In questa tesi mi sono focalizzata sullo studio delle proprietà plastiche delle rappresentazioni del corpo e dello spazio peripersonale. Ho sviluppato una serie di metodi per valutare il confine dello spazio peripersonale (Capitolo 4), per studiare i suoi correlati neurali (Capitolo 3) e per valutare le rappresentazioni multisensoriali del corpo. Questi compiti sono stati usati per studiare modificazioni plastiche del corpo e dello spazio peripersonale in seguito all’utilizzo di uno strumento (Capitolo 5), in seguito a una stimolazione multisensoriale (Capitolo 6), amputazione e impianto di protesi (Capitolo 7) e nell’ambito delle interazioni sociali. I risultati ottenuti hanno mostrato come la modificazione nella funzione (in seguito all’utilizzo di uno strumento) o della struttura fisica (in seguito ad amputazione ed impianto di protesi) del corpo determinano una estensione o una contrazione sia della rappresentazione dello spazio peripersonale che della rappresentazione del corpo. Inoltre, i risultati ottenuti hanno dimostrato che la rappresentazione dello spazio peripersonale viene plasmata anche dalle interazioni sociali. Tale livello di plasticità suggerisce che l’esperienza del nostro corpo viene continuata costruita e aggiornata tramite le diverse esperienze.

Lesions to the primary geniculo-striate visual pathway cause blindness in the contralesional visual field. Nevertheless, previous studies have suggested that patients with visual field defects may still be able to implicitly process the affective valence of unseen emotional stimuli (affective blindsight) through alternative visual pathways bypassing the striate cortex. These alternative pathways may also allow exploitation of multisensory (audio-visual) integration mechanisms, such that auditory stimulation can enhance visual detection of stimuli which would otherwise be undetected when presented alone (crossmodal blindsight). The present dissertation investigated implicit emotional processing and multisensory integration when conscious visual processing is prevented by real or virtual lesions to the geniculo-striate pathway, in order to further clarify both the nature of these residual processes and the functional aspects of the underlying neural pathways. The present experimental evidence demonstrates that alternative subcortical visual pathways allow implicit processing of the emotional content of facial expressions in the absence of cortical processing. However, this residual ability is limited to fearful expressions. This finding suggests the existence of a subcortical system specialised in detecting danger signals based on coarse visual cues, therefore allowing the early recruitment of flight-or-fight behavioural responses even before conscious and detailed recognition of potential threats can take place. Moreover, the present dissertation extends the knowledge about crossmodal blindsight phenomena by showing that, unlike with visual detection, sound cannot crossmodally enhance visual orientation discrimination in the absence of functional striate cortex. This finding demonstrates, on the one hand, that the striate cortex plays a causative role in crossmodally enhancing visual orientation sensitivity and, on the other hand, that subcortical visual pathways bypassing the striate cortex, despite affording audio-visual integration processes leading to the improvement of simple visual abilities such as detection, cannot mediate multisensory enhancement of more complex visual functions, such as orientation discrimination. / Una lesione alla via visiva primaria (genicolo-striata) causa cecità nel campo visivo controlesionale. Ciononostante, studi precedenti suggeriscono che, mediante vie visive alternative che non coinvolgono la corteccia striata, i pazienti con deficit di campo visivo potrebbero ancora riuscire ad elaborare implicitamente la valenza affettiva degli stimoli emotivi non visti (affective blindsight) e di sfruttare meccanismi multisensoriali (audio-visivi), cosicchè la stimolazione uditiva migliori la detezione visiva di stimoli non percepiti quando presentati da soli (crossmodal blindsight). Nella presente tesi si sono indagate l’elaborazione emotiva implicita e l’integrazione multisensoriale osservabili quando l’elaborazione visiva cosciente è impedita da lesioni reali o virtuali della via genicolo-striata, in modo da chiarire sia la natura di tali processi sia gli aspetti funzionali dei circuiti neurali sottostanti. Le evidenze sperimentali qui presentate dimostrano che, in assenza di elaborazione corticale, le vie visive alternative sottocorticali consentono l’elaborazione implicita del contenuto emotivo delle espressioni facciali, ma che tale abilità è limitata alle espressioni di paura. Questo suggerisce l’esistenza di un sistema sottocorticale specializzato nella detezione di segnali di pericolo a partire da segnali visivi grezzi, permettendo dunque il rapido reclutamento di risposte comportamentali di lotta o fuga già prima che possa avvenire un riconoscimento conscio e dettagliato delle potenziali minacce. Inoltre, la presente tesi estende le conoscenze riguardo ai fenomeni di “crossmodal blindsight”, dimostrando che, a differenza della detezione visiva, la discriminazione di orientamento di linee non può essere migliorata dalla presentazione di suoni quando la corteccia striata non è funzionante. Questo dato suggerisce da un lato che la corteccia striata ha un ruolo causativo nel miglioramento “cross-modale” della sensibilità visiva all’orientamento e, dall’altro, che le vie visive sottocorticali che non coinvolgono la corteccia striata, anche se permettono l’integrazione di segnali audio-visivi e il miglioramento della semplice detezione, non possono potenziare abilità visive complesse, come la discriminazione di orientamento