Every day we use actions, gestures and words to interact with other people and with the environment. Being able to understand people’s movements and communicative intentions is critical to our ability to act successfully in the world. Here we present three studies aiming at investigating the relationship between actions, gestures and words in the brain. In the first study we described and offer a standardized data set of 230 well-controlled stimuli of meaningful (pantomimes and emblems) and meaningless gestures together with norms, with the aim of promoting replicability between studies. One hundred and thirty raters (Italian and non-Italian speakers) rated the meaningfulness of the gestures, and provided a name and a description for each of them. To our knowledge, this is the first data set of meaningful and meaningless gestures presented in the literature. In the second study, we aimed 1) at characterizing the neural network associated with the processing of different categories of gestures (pantomimes, emblems and meaningless gestures) using fMRI, and 2) at contrasting the role of precentral and temporal areas in action understanding, using rTMS. In particular, we applied rTMS to the posterior middle temporal gyrus (pMTG) and to the ventral premotor cortex (PMv) in different sessions, while participants were performing either a semantic or a perceptual judgment task. According to motor theories of action understanding, rTMS applied to the PMv, but not to the pMTG, should impair performance during the semantic judgment task. By contrast, according to cognitive theories of action understanding, rTMS applied to pMTG, but not to PMv, should impair performance in this task. Results from the fMRI experiment revealed a sensitivity of the MTG to meaningful in comparison to meaningless gestures. Additionally, three different brain areas seemed to contribute to the processing of pantomimes and emblems: superior parietal lobe (SPL) and precentral gyrus (PCG) in the case of pantomimes and IFG in the case of emblems. Unfortunately, we did not observe any significant effect of rTMS in any condition. The third study aimed at investigating how pantomimes, emblems and words are organized in the middle temporal gyrus, using fMRI. We observed a posterior-to-anterior structure, both in the left and in the right hemisphere, that might reflect the input modality and also the arbitrariness of the relationship between form and meaning.

Reward cues acquire distinctive incentive properties from their association with motivationally significant outcomes. These incentive properties are manifest in an augmented salience that provides reward cues with the capacity to attract attention, also in contexts where pursuing the reward is not relevant. I will first examine the unresolved debate concerning the learning parameters that define the cue-reward association and eventually modulate attention. Specifically, whether the cue attentional salience is governed by reward expectancy or uncertainty. I will then study another incentive property of reward cues, that is the ability to strengthen the performance of a separately learned instrumental action exerted to obtain an outcome, a phenomenon known as Pavlovian-Instrumental transfer (PIT). Since the motivational value of reward is altered when reward is devalued, an interesting question is whether the incentive properties of reward cues change accordingly, both in the attentional and in the operant domain. Therefore, I will investigate the effects of motivational shifts on the incentive properties of reward cues, by means of reward devaluation. In the context of the ability of a cue attentional salience to update in accordance with the altered outcome value, I will further analyze the influence of incentive learning (i.e. the possibility to re-associate the cue with the devalued outcome). The procedures adopted through the experiments share two main phases: a learning phase in which human thirsty participants learned cue-beverage reward associations involving different contingencies, and a test phase in which no reward was delivered. During the learning phase, participants accumulated the beverage reward that acted as an incentive, since it was not consumed through this phase. This allowed a controlled devaluation procedure by consummatory satiation (i.e. a motivational shift) that was administered at different moments during the experiments depending of the hypothesis at test. Results showed that the cues that better predicted the reward during learning were the stimuli preferentially attended at test, and the stimuli that invigorated more the instrumental action for the outcome. These incentive attributes persisted despite reward devaluation: the attentional bias and the PIT effect emerged unaltered after participants quenched their thirst. Reward cues persisted in capturing attention after reward devaluation even when participants were given the chance for incentive learning by means of an additional learning phase. Taken together, the evidence that emerged indicates that the incentive properties of reward cues, once acquired, can surprisingly and irrationally outlast reward devaluation and can resist incentive learning, suggesting that some incentive properties of the cue can become independent from those of the reward. These results may provide important implications for the understanding of the psychological mechanisms underlying different types of addiction.

Acting in the world in a way that matches our goals, overriding impulses, is one of the first abilities that we must learn while growing up. We often change the course of our actions because of external influences or because we simply “change our mind”. As John H. Patterson said, “Only fools and dead men don't change their minds. Fools won’t. Dead men can’t”. An important distinction must first be made between the impact of internal and external sources on action decisions, and the first part of the introduction will be devoted to this topic. In the second part, I will discuss the topic of inhibitory control. In the scientific literature, action inhibition is often treated as a unitary phenomenon, while the distinction among different types of inhibitions might explain the diverse results and be useful for future studies. My experimental work has been devoted to both externally-triggered and internally-driven voluntary action inhibition, in particular, in Experiment 1 I conducted a set of studies aiming at understanding the underlying cortical circuits for internally-driven action inhibition, whereas Experiment 2 focused on proactive inhibition mechanisms. While it is beyond the scope of this manuscript to cover the entire literature on inhibitory control, I would like to propose a common view to unify the different theories concerning how the brain exerts voluntary inhibitory control and provide some suggestions for future investigations to study the way we flexibly control our actions to cope with the constantly changing external, and internal, environment.

L'obiettivo generale di questa tesi è chiarire il modo in cui alcune variabili, prossimali e distali, influenzano lo sviluppo psicofisico del bambino all' interno di un campione di madri a rischio del progetto Scommettiamo sui giovani. Qualora i risultati descritti in questo lavoro confermassero i dati presenti in letteratura, la Provincia Autonoma di Trento potrebbe applicare sul territorio una serie di servizi rivolti alle madri a rischio e non, e attuare interventi di supporto alla genitorialità. L'organizzazione della tesi prevede una parte teorica introduttiva, la presentazione di quattro articoli scientifici, in corso di pubblicazione, riguardanti diverse aree di interesse (articolo 1: Le madri a rischio e il quoziente di sviluppo dei bambini; articolo 2: L'indice di attaccamento dei bambini in un campione di madri a rischio; articolo 3: Il parenting nei contesti di immigrazione; articolo 4: Valutazione preliminare dell'efficacia dell'intervento di supporto alla genitorialità a rischio in Trentino e un capitolo finale sulle conclusioni generali e sulle ricerche future.

Over the last years several results demonstrated that context-based expectations on both word-class and concepts influence the word processing at very early stages, namely at sensory analysis level. Given that these early effects are modulations of the process of stimulus analysis they depend on physical and orthographical properties of critical words in interaction with linguistic expectations. This evidence on early effects is in contrast with a syntax-first approach for which the cognitive system builds at first the syntactic structure by exploiting word-class information only. This strong syntax-first assumption pushed forward by Friederici (2002) model is based on a very early ERPs effect with latency around 150 ms that is elicited by word-class violations (eLAN: early left-anterior negativity). I studied three linguistic violations with an ERPs sentence processing paradigm. In two studies in Italian word-class violations on prepositions and verbs were implemented, overcoming the more important methodological limitations of previous studies on word-class violations. In a third study we investigated determiner-noun gender agreement in Italian using nouns for which grammatical gender is expressed unambiguously by a long derivational morpheme, that is very salient at orthographic and visual level. ERPs results show a LAN (300ms latency) followed by a P600 (500ms latency) for all the conditions. The lack of replicability of eLAN, already discussed in the literature, makes Friederici (2002) model difficult to be maintained. The ERPs elicited by gender disagreeing nouns also show an effect on the amplitude of the N250 (200ms onset), an effect specific to morphological processing since a previous study with no control on how gender was expressed reported a LAN+P600 pattern only (Molinaro et al., 2008). The latter result shows that gender agreement can affect word recognition (at least the morphological parsing) during sentence processing earlier than violation detection indexed by the LAN. This result enrich the evidence about early context top-down effects that are different from syntagmatic structural processing.

L'Infant research ha ampiamente dimostrato l’importanza e gli effetti che le interazioni precoci hanno sullo sviluppo mentale del bambino (Stern, 1985; Tronick Tronick, 1989; Emde, 1985; Greenspan, 1997). Nell’ambito dello sviluppo atipico (SA) diversi studi mettono in luce la presenza di alterazioni precoci della sfera interattiva genitore bambino che hanno una ricaduta negativa sullo sviluppo mentale del bambino, già in parte compromesso dai deficit neurobiologici (Dawson, Hill, Spencer, Galpert, & Waston, 1990; Doussard-Rossevelt, Bazhenova, & Porges, 2003; Hodapp, 2002; Kasari, Sigman, Mundy & Yirimiya, 1988; Venuti, Esposito, 2008; Venuti, de Falco, Esposito, Bentenuto, Villotti & Bornstein, 2008; de Falco, Cimmino, La Femina & Venuti, 2008). Scopo generale dello studio è la verifica degli effetti di un intervento genitore bambino con SA il cui obiettivo è la promozione di una modalità interattiva maggiormente sincronica e responsiva. In particolare si intende indagare gli effetti del trattamento su tre aree specifiche: l’interazione genitore bambino, le rappresentazioni del genitore e lo sviluppo del bambino. Lo studio è stato condotto su quattro diadi genitore bambino con SA, con età compresa tra i 30 e i 54 mesi. Due bambini hanno una diagnosi di Disturbo Pervasivo dello Sviluppo (PDD) e uno di Ritardo Mentale (RM). La ricerca è stata effettuata mediante il disegno sperimentale su singolo soggetto senza gruppo di controllo. Per valutare degli effetti del cambiamento nelle tre aree indagate sono state applicate diverse misure pre e post trattamento e misure osservative ripetute nel tempo. Per tutte le misure ripetute sono state calcolati i livelli di attendibilità sul 33% delle osservazioni attraverso il test k di Cohen. L’analisi degli andamenti delle sedute mettono in evidenza la presenza di incrementi percentuali significativi in diverse aree indagate. In particolare, si è rilevato l’aumento del livello di disponibilità emotiva e di sincronia della diade; un aumento delle attribuzioni positive rispetto al proprio figlio e alle capacità genitoriali; infine, rispetto allo sviluppo del bambino si è registrato un aumento del livello di autoregolazione e di intenzionalità sebbene in misura diversa nei tre soggetti.

In this thesis I will talk about social robots, their appearance, and people’s concerns about potential negative impacts that social robotics technology could have on humans and their identity. The aim is to contribute to the understanding of why people fear social robots, and what the role of humanlike appearance is within this process. Social robots represent a new, fascinating technology. Research in social robotics not only develops new and better social robots but also tries to understand and prevent eventual problems that could arise when people and robots coexist. Moreover, the relations and reactions to social robots, especially those who highly resemble humans, is also an interesting topic from a social psychology point of view. Taking up professor Ishiguro’s words, developing androids opens up the question of “what is human?”. The study of psychological processes related to machines that imitate real persons allows us to know more about ourselves as human beings.

Despite the large amount of work that has been conducted since Donald’s Hebb work and described in his famous dissertation “The Organization of Behavior” (Hebb, 1949), understanding the experience-dependent mechanisms of plasticity within the primary visual cortex (V1) remains a major priority. Although plasticity effects are strongest during the critical period (early development), studies on cortical plasticity from the last two decades have clearly demonstrated that the human brain is plastic and amenable to changes throughout life. Perceptual Learning (PL) is one of the most commonly used procedure to promote visual improvement in neurotypicals and recovery of functions in a variety of disorders. However, a common feature to most of the training protocols is that they require long time and a high number of sessions to show effective improvement. Recently, non-invasive brain stimulation (NIBS) techniques, specifically transcranial random noise stimulation (tRNS) and anodal tDCS, have been used to modulate activity within the visual cortex to enhance perceptual learning. However, the mechanisms of action and the long-term effects on learning are still unknown. The questions this thesis work will address are the following: (1) can neuromodulatory techniques be used to boost visual perceptual learning in neurotypicals, which technique is the most effective and what are the long term effects on learning? (2) what are the potential underlying physiological mechanisms modulating cortical excitability of the visual cortex? and (3) contingent upon results from (1), can NIBS be used over early, peri-lesional visual areas during visual training to induce recovery of visuo-perceptual abilities in chronic partial cortical blindness (CB)? I used tRNS coupled with visuo-perceptual training protocols to promote fast and sustained perceptual learning in neurotypicals. I then provide evidence that tRNS can increase cortical excitability of the visual cortex, measured by priming early visual areas with tRNS, before measuring phosphene threshold with single pulse TMS. Lastly, I provide preliminary

Objects belonging to different categories elicit reliably different response patterns in human ventral temporal cortex, with the most prominent distinction being that between animate and inanimate objects. However, it remains unclear whether these categorical distinctions genuinely reflect object category or, alternatively, category-associated visual properties. To address this question, we designed a stimulus set in which animate and inanimate stimuli were carefully matched for shape. Different aspects of visual similarity of the stimuli were measured in three behavioral visual search tasks. We then conducted an fMRI study to test the hypothesis that animate-inanimate organization in VTC response patterns can be explained by visual properties of these categories. We found that it was not the case: although visual dissimilarity predicted neural dissimilarity across the visual cortex, we also found regions in which category information was present even after regressing out visual dissimilarity. We then conducted an MEG study to examine the time course of shape- and category-related information in the brain. Following the analysis approach used in the fMRI study, neural dissimilarity of MEG sensor patterns was modeled using regression analysis, where visual dissimilarity and categorical dissimilarity served as predictors of neural dissimilarity. The results show that visual object properties were strongly contributing to MEG sensor patterns. Surprisingly, when regressing out the contribution of visual properties, no residual category information was present in MEG response patterns. These results suggest that MEG sensor patterns evoked by visually presented objects predominantly reflect visual object properties. Taken together, these findings suggest that MEG is less sensitive to object category information that is independent of shape information.

In daily life, we frequently execute reaching movements, for example to be able to grasp our mobile phone. The processing of movement direction is fundamental to efficiently reach the target object. Many neurophysiological studies reported neuronal populations selective for movement direction in many regions of the monkey brain. In my thesis, I investigated which areas in the human brain show directional selectivity. Moreover, I measured to what extent directional selective regions are sensitive to changes in other movement parameters, like the type of motor act and movement amplitude. In three functional magnetic resonance imaging (fMRI) experiments, participants were adapted to execute reaching movements in the adaptation direction. Occasionally, test trials were presented. Test trials differed from adaptation trials in movement direction only, or in movement direction as well as in another movement parameter (Experiment 1 and 2: type of motor act; Experiment 3: movement amplitude). By comparing the fMRI signal in conditions where only movement direction was manipulated with conditions where also other movement parameters changed, we were able to measure sensitivity of directionally tuned neuronal populations to these additional movement parameters. Multiple regions in the human visuomotor system showed selectivity for movement direction. This selectivity was modulated by the type of motor act to varying degrees, with the largest effect in M1 and the smallest modulation in the parietal reach region. Moreover, directional selectivity was clearly sensitive also to changes in movement amplitude. These results extend the current knowledge on the representation of actions from monkey physiology to the human brain and furthermore may have important practical implications for restoring lost motor functions in tetraplagic patients.