Il presente lavoro ha lo scopo di studiare in dettaglio l’interazione genitore-bambino in famiglie con bambini con Disturbo dello Spettro Autistico (che verranno sintetizzati con l’acronimo ASD dalla definizione inglese “Autism Spectrum Disorder”). I disturbi dello spettro autistico sono disordini del neurosviluppo che alterando nei primi anni di vita la capacità di mettersi in relazione con gli altri, determinano gravi effetti cognitivi, affettivi e comportamentali. Le ricerche condotte negli ultimi decenni nell'ambito della psicologia dello sviluppo hanno evidenziato il ruolo centrale delle relazioni genitoriali nello sviluppo del bambino, sia in bambini con sviluppo tipico che con sviluppo atipico. Questo lavoro di tesi ha l’obiettivo di osservare alcuni aspetti peculiari dell’interazione genitore-bambino in bambini con disturbo dello spettro autistico, considerando come il deficit a livello del “cervello sociale” si ripercuote sullo strutturarsi e il mantenersi di questa relazione. Nel presente lavoro si collocano quattro studi. In particolar modo saranno analizzate nel primo studio le caratteristiche del gioco in diadi madre-bambino con ASD confrontandole con diadi madre-bambino in cui il bambino presenta la Sindrome di Down o lo sviluppo tipico al fine di evidenziare similitudini e differenze sia nelle abilità manifestate dalle madri sia per quelle espresse dai bambini. Nel secondo studio, verrà approfondito l’aspetto del gioco specificatamente in interazione madre-bambino e padre-bambino in famiglie con bambini con ASD, al fine di osservare se la capacità di gioco manifestate dal bambino si differenzino in base alla figura genitoriale con cui stanno interagendo e per evidenziare se madre e padre evidenziano delle caratteristiche peculiari in base al ruolo genitoriale rivestito. Il terzo studio, invece, si è concentrato sull’analisi dello scambio sincronico all’interno delle diadi madre-bambino con disturbo dello spettro autistico confrontandolo con interazioni con bambini con sviluppo tipico e sindrome di Down, con lo scopo di osservare più in dettaglio la struttura dello scambio diadico per evidenziare i contribuiti specifici di entrambi i membri della diade, mostrando come possano differire in base alla presenza o meno di una patologia. Infine nel quarto studio sarà osservata la disponibilità emotiva diadica all’interno di famiglie di bambini con disturbo dello spettro autistico, analizzando sia i comportamenti del bambino sia i comportanti delle due figure genitoriali.

For decades, works in psychology of thinking and decision making have been reporting suboptimal performance and systematic departures from the axioms of probability theory in people’s probability judgments. In these first works, poor performance was often attributed to people making normatively wrong intuitions because of their limited cognitive resources and lack of statistical skills. Over the last years, studies that considered various Bayesian models of inductive reasoning but also other high and lower-level cognitive processes provided a more optimistic picture by showing that, despite departing from the normative benchmark, people’s reasoning skills lead to adaptive and sound performance in everyday life. Different explanatory accounts for this suboptimal but sound reasoning have been proposed, some being more compelling than others. The present thesis is aimed at exploring one of these accounts that is based on confirmation relations and suggests that human inductive ability might rely more on estimating evidential impact than posterior probability. So far, this account has been applied to classical probabilistic reasoning errors, linguistic and psycholinguistic phenomena and probabilistic inferences with verbal stimuli. In this study, we tried to see whether the implicit estimation of confirmation relations can affect probability judgments also when the link between evidence and hypotheses is operationalized as the arbitrary association between visual features in briefly presented figures. First, we expected participants to consider confirmed hypotheses more probable than corresponding (in terms of posterior probability) disconfirmed ones; second, we expected them to choose the more likely option (i.e. the normatively correct one) more often when it was confirmed by the evidence provided than when it was disconfirmed. Four computer-based experiments were conducted using the same methodology. Experimental stimuli consisted of inductive arguments concerning 40 sets of figures composed of two features with two possible values each. By varying the probabilistic association between the two values of the features, sets were generated to have, for each possible combination of the two features, two arguments with the same posteriors and opposite impacts. In each trial, participants first looked at a set of figures. One of these figures was then randomly drawn. Participants were informed about the value of one feature of the drawn figure (e.g., that it was a “circle”) and had to guess the value of the other feature (“white” vs. “black”). Throughout the four experiments, we used three different combinations of features: color and shape (exp.1: black/white; exp 2: light/dark grey), pattern and shape (exp 3) and type and orientation of line (exp 4). In all four experiments, participants systematically chose the confirmed alternative over the equally probable, but disconfirmed one, and chose the normatively incorrect (i.e. less likely) alternative more often when it was confirmed (vs. disconfirmed) by the evidence provided. These results provided a first empirical evidence of the effect of confirmation relations on probability judgment with perceptual stimuli, but also highlighted a significant influence of the experimental material itself on choice patterns. In fact, in experiments 1 to 3 the obtained results showed that color (or pattern) was a more compelling evidence than shape in determining participants’ choices. The combination of line curvature and orientation used in experiment 4 proved to be the more balanced among those employed in the present research. Only in this last experiment, indeed, the type of evidence did not affect the choice for the confirmed alternative, nor the amount of errors. The results we found supported our experimental claims showing that confirmation relations can affect probability judgments even in absence of any semantic element, but also suggested the existence of a mutual influence between perceptual features and probability judgments. Our experimental results have theoretical as well as applied implications. On a theoretical level, they extend the results coming from works involving verbal and linguistic material to perceptual stimuli with no semantic background. Additionally, they show that high-level relations, which are completely unknown to the subject, affect the way people perceive relations within a visual set of perceptual items. This might have interesting and noteworthy implications for studies on visual cognition, and, on a broader level, contingency learning and stereotypical judgments.

The current thesis aims to investigate cascaded processing in visual word recognition by testing the predictions of the Dual Route Cascaded (DRC) model of reading. Despite widespread acceptance of the idea that visual language processing is cascaded, there are circumstances in which such an account is not easily reconciled with the data produced by skilled readers. Recent experiments involving factorial manipulations in reading showed, in particular, additive effects of stimulus quality (i.e., clear vs. degraded stimuli) with letter string length and orthographic neighbourhood size in nonword reading and with word frequency and lexicality when words and nonwords were mixed in the task, thus suggesting that information processing implicated in visual word recognition must be at least partially thresholded. Six experiments have been presented in this thesis: on one hand, a new variable that has a role when the stimuli are degraded – the Total Letter Confusability – has been introduced; on the other hand, the effects due to list composition have been analyzed when the stimuli were degraded in the task. In general, the results obtained suggest a novel interpretation of the additivities previously observed; these findings have been explained within the DRC model which also correctly simulates a significant amount of the data. The empirical evidence collected so far clearly indicates that there is currently no need to assume thresholded processing in the reading system.

Reward is a strong determinant of human and non-human behavior, influencing the exploration of the world around us and our interactions with it. Interestingly, the impact of reward and reward-associated objects is not limited to strategic changes in approach behavior or attention deployment, but also extends to situations in which prioritizing processing of such objects is not necessarily advantageous for current goals. In spite of converging evidence for the automatic influence of reward on attentional deployment, less is known about the impact of reward on other cognitive processes. In this thesis I describe a first attempt to investigate the influence of reward in encoding and maintenance of visual representations in working memory. Throughout this thesis I argue that once objects have been associated with a positive outcome in past encounters, they are preferentially encoded and maintained in visual working memory (VWM) even when reward is no longer provided or when there is no consistent pairing between reward feedback and target identity. In Chapters 2 and 3 I demonstrate that reward associated objects interfere with the visual representations of less valuable items maintained in VWM. This interference was already present starting 10 ms from the offset of the memory display suggesting that valuable objects directly affected the encoding of less valuable items. This robust phenomenon was observed at different delays, both when reward-associated objects were task-relevant and when they were not, and was independent of object salience. However, the interference disappeared when task requirements for target selection increased suggesting that items with a positive reward history can effectively capture attention and interfere with VWM representations only when cognitive resources are not exhausted by the main task (Chapter 3). In the last study presented in this thesis I explored the possibility that reward could impact VWM beyond target selection and encoding, namely influencing the active maintenance process. To investigate this hypothesis I measured reward priming effects on event-related potential (ERP) indices of selective attention – the N2pc - and visual working memory maintenance – the CDA (contralateral delay activity). Results indicate that reward modulated CDA only, speaking for a discrete effect of reward on VWM maintenance. While the precise nature of such modulation is still unknown, these results suggest that reward history might influence the precision or the duration of visual representations maintained in VWM. Further studies are necessary to directly test this hypothesis, but these initial results suggest an interesting direction for future research in better characterizing the nature and extent of the influence of reward history on visual cognition.

Cross-modal processing and multisensory integration (MSI) can be observed at early stages of sensory processing in the cortex. However, the neurophysiological mechanisms underlying these processes and how they vary across sensory systems remain elusive. The aim of this study was to investigate how cross-modal processing and MSI are reflected in power and phase of oscillatory neuronal activity at different temporal scales in different sensory cortices. To this goal, we recorded stereo-electroencephalographic (SEEG) responses from early visual (calcarine and pericalcarine) and auditory (Heschl’s gyrus and planum temporale) regions in patients with drug-resistant epilepsy while performing an audio-visual oddball task. To Investigate crossmodal processing and MSI in the power domain of oscillatory activity, we explored a wide range of frequency bands (theta/alpha band: 5-13Hz; beta band: 13-30 Hz; gamma band: 30-80 Hz; high-gamma band: 80-200 Hz) during the first 150 ms post-stimulus onset. Differently, to investigate crossmodal processing and MSI in the phase domain of oscillatory activity, we explored a narrow range of frequency bands (theta/alpha band: 5-13Hz; beta band: 13-30 Hz; gamma band: 30-80 Hz) during the first 300 ms post-stimulus onset. In the power domain, we showed that cross-modal processing occurs mainly in the high-gamma band (80-200Hz) in both cortices. However, we evidenced that the way MSI is expressed across modalities differs considerably: in the visual cortex, MSI relies mainly on the beta band, however it is also evident, to a lesser extent, in the gamma and high-gamma band, while the auditory cortex reveals widespread MSI in the high-gamma band and, to a lesser extent, across the gamma band and the other investigated frequency bands. In the phase domain, we showed that cross-modal processing is differently expressed across modalities: in the auditory cortex it induces an increased phase concentration index (PCI) in ongoing oscillatory activity across all the investigated frequency bands, while, in the visual cortex, it induces an increased PCI particularly evident in the theta/alpha band with few or no effect respectively in the gamma and beta band. Importantly in both cortices, the most part of the COIs showing increased PCI, were not accompanied by a concomitant increase in power. These results indicate that in both auditory and visual cortex, cross-modal processing induces a pure phase resetting of the oscillatory activity. During MSI processing we observed, in both cortices, a stronger increase in PCI, in comparison to the intramodal processing, in the theta/alpha band and in the gamma band. Our results confirm the presence of cross-modal information representations at neuronal populations level and conform to a model where the cross-modal input induces phase-locked modulation of the ongoing oscillations. Importantly, our data showed that the way MSI is expressed in power modulations differs between the investigated sensory cortices suggesting the presence of different types of neurophysiological interactions during this process. These results are discussed in the framework of the current literature.

The present thesis investigates the effects of auditory deafferentation and reafferentation with a unimodal and multisensory perspective. Aim of the thesis is the understanding of issues concerning functional plasticity resulting from long-term auditory deprivation, and the effects of reafferentation through a cochlear implant (CI) on audition, vision, and their interaction. The thesis is divided into three parts: Part I explores the effects of auditory deafferentation on the visual modality to understand whether a long-term sensory deprivation leads one of the remaining senses to reorganise in a cross-modal fashion. In particular, Chapter 1 reviews animal and human findings on cross-modal plasticity after sensory deafferentation and introduces the particular case of deafness, focusing on the sensory modality that seems to reorganise the most after profound deafness: vision. In Chapter 2 I present the study we conducted to explore an underinvestigated issue of cross-modal reorganisation after long-term auditory deprivation. We investigated visual temporal processing in a group of profoundly deaf individuals by testing their ability to make temporal order judgments. Our results show comparable accuracy in processing visual temporal sequences in deaf individuals and hearing controls, but an enhanced reactivity in the deaf population particularly when responding to stimuli appearing towards the periphery of the visual field. Our findings suggest that long-term auditory deprivation does not alter temporal processing abilities, and that the reactivity observed in the deaf group may instead constitute a central aspect of the functional changes occurring after auditory deafferentation. Part II of the thesis addresses the effects of auditory reafferentation through a cochlear implant on the adult auditory system. Chapter 3 reviews findings that document plasticity in the adult brain and the role of experience in determining the extent for plasticity to occur. In addition, a review on auditory spatial hearing introduces the two studies we conducted to investigate the recovery of sound localisation abilities after bilateral and unilateral cochlear implantation (chapter 4 and 5, respectively). Results from the first study show that partial recovery of spatial hearing after bilateral implantation occur with different time course as a function of the recipient’s experience with auditory cues. Results from the second study show that some sound localisation abilities can emerge even in prelingually deafened adults fitted with a single implant, at least in a laboratory setting. Importantly, this ability appears to be constraint by the years of experience with the CI, and again as a function of previous auditory experience of the CI recipient. Part III addresses the question of the effects of auditory reafferentation on the visual system and its interaction with audition. Chapter 6 reviews the issue of cross-modal plasticity after auditory reafferentation. In particular, we investigated whether visual abilities are modified after cochlear implantation in a group of prelingual and postlingual deaf recipients (Chapter 7). In this study we found that prelingual deaf recipients, compared to postlingual deaf, had an advantage in detecting the onset of rapidly presented visual stimuli in the periphery of the visual field. In a further experiment (Chapter 8) we investigated whether auditory and visual information are integrated after cochlear implantation in prelingual and postlingual deaf recipients and found that their abilities are comparable to hearing controls. Finally, Chapter 9 summarises all the presented results and draws the major conclusions.

How humans perceive everyday reality is one of the most fascinating and enduring interest of different scientific disciplines. The aim of the present dissertation is to investigate - from both a theoretical and an empirical perspective - some aspects concerning the crossmodal interactions between hearing and vision. In the first part of the introduction special attention is given to the cortical and subcortical neural substrate involved in integrating different sensory modalities, and more specifically, audiovisual stimuli. Experimental studies in the literature designed to empirically investigate different aspects of audiovisual interaction and the potential existence of a sensory dominance between hearing and vision will be presented. In the last part, the introduction will be focalized to discuss some of the principal models aimed to predict the outcome of audiovisual integration and its relation with sensory dominance. The following chapters present the experimental studies designed to empirically investigate different aspects of audiovisual interactions and the role of eye movements in auditory cognition. In a first study, the effects of eye movements on auditory spatial representation will be explored. The aim is to disentangle controversial results in the literature emerged in two studies that used different type of sounds (i.e., free field sounds provided through loudspeakers vs. sounds provided intracranially through headphones) and different tasks. In a second study, the disputed relation between perception and action will be investigated in presence of a crossmodal audiovisual illusion. The aim is to verify whether participants’ visuo-motor behaviour might be biased by the visual illusion as emerged for perception, and eventually, whether perceptive and motor biases are correlated. The last study presented in this dissertation will explore the effects of crossmodal audiovisual stimulation in low vision patients and the relation between the visual pathology. More precisely, the possible visual detection enhancement provided by a sound coupled with a visual stimulus will be investigated. To this purpose, in a first experiment, the effect of spatial disparity between audiovisual stimuli will be deepened while the last two experiments will be focalized on the effects of temporal audiovisual disparities of crossmodal stimuli. The results of the studies described in the present dissertation provide evidence of an effect of eye movements in the auditory spatial cognition and a relation between the perceptive and visuo-motor systems in presence of an illusion induced by a sound. Moreover the presented findings report for the first time a significant crossmodal effect of audition on visual perception in low vision patients.

Numerosi studi considerano il sottotrattamento del dolore pediatrico uno dei problemi più critici associati alla cura e degenza ospedaliera (Schechter et al., 2002). La soluzione risiede in una valutazione accurata e sistematica dello stato di algesia del paziente (Reaney, 2007); tuttavia, vi è una notevole reticenza all’impiego costante e regolare di scale di valutazione del dolore nei reparti pediatrici (Zernikow et al., 2005). Questa tesi si propone due obiettivi: innanzitutto, osservare l’atteggiamento degli operatori sanitari circa l’impiego di scale di valutazione del dolore nelle Unità Operative pediatriche di due Ospedali del Trentino. In particolare, si vuole stabilire se a livello locale sussistono le medesime condizioni evidenziate dalla letteratura internazionale sull’argomento; quindi, indagare le cause del problema, e verificare l’effetto che una semplice restituzione con feedback costruttivo ha sulle modalità di valutazione del dolore pediatrico nelle U.U.O.O. così trattate.

Oscillatory neuronal activity in the alpha band has been associated with both conscious perception and attention. Firstly, conscious perception of a weak sensory stimulus is preceded by alpha power decreases. Secondly, attention to a sensory event reduces alpha activity in the corresponding sensory regions. According to the widely accepted functional inhibition hypothesis, oscillatory neural activity in the alpha band reflects cortical excitability; in other words, a sensory region with low alpha power levels is more excitable. Several questions regarding the relationship between conscious perception, attention and alpha band activity have not been addressed so far. Firstly, it remained unclear whether brain states predisposing consciousness only comprise local pre-stimulus alpha power decreases, or also global network states. Secondly, it remained unclear whether alpha power decreases prior to conscious perception are confounded by fluctuations of attention or not. The goal of the current thesis is to address these two open questions in the tactile modality with two magnetoencephalography studies. The first study explored brain states predisposing conscious tactile perception, with a particular focus on functional connectivity patterns in addition to alpha power modulations. To this end, a simple near-threshold detection paradigm was conducted, with weak tactile stimuli to the participants’ left index finger. Findings revealed that conscious perception is preceded by a) a relative alpha power decreases in the somatosensory cortex contralateral to stimulation, and b) a spectrally specific pattern of functional connectivity in the primary somatosensory cortex. Based on the first study, it can be concluded that brain states predisposing consciousness comprise local cortical excitability changes as well as frequency-specific network patterns. The second study focused on alpha power changes prior to conscious perception in the context of spatial attention. To this end, a near-threshold detection paradigm with a double-pulse target stimulus was combined with a spatial attention task. The results showed a) that spatial tactile attention modulates pre-stimulus alpha power, and b) that spontaneous alpha power fluctuations not explained by attention influence perception. These findings indicate that – while attention does affect pre-stimulus alpha power levels – spontaneous alpha power fluctuations predispose consciousness. Taken together, we conclude that brain states predisposing conscious perception comprise spectrally specific functional connectivity patterns, and alpha power fluctuations distinct from attention-induced alpha power modulations.

An observer who approaches a planar surface that rotates about the vertical axis (e.g. a flag hinging on a pole) generates the same Optic Flow (OF) that is produced by a planar surface that rotates about an horizontal axis viewed by a static observer. In spite of this ambiguity, perceived surface orientation by the active observer is usually veridical. This result is consistent with an interpretation of the OF that takes into account egomotion signals (1). Here, we suggest an alternative interpretation based on a computational model that ignores linear egomotion signals (2, 3). An implication of our model is that perceived orientation should flip by 90 degrees whenever the OF undergoes a translational motion in a direction orthogonal to the surface axis of rotation. OF translational motion is always present when an observer moves towards or away from a stimulus display, due to the natural rotations and translations of the head. Main conclusion: In the present experiments, we tested our alternative explanation by asking observers to judge surface orientation in three conditions: 1) when a random-dot planar surface is rotated about a stationary axis, 2) when the axis of rotation was tethered to a coordinate system centered on the observer’s head, so as to eliminate the translational components of the OF, and 3) when a translational component was added to the OF produced in 2). The results are consistent with the predictions of our model. Perceived surface orientation (i) was veridical in 1), (ii) was ambiguous in 2), and (iii) underwent a 90 degrees flip with respect to veridical in 3). A similar pattern of results was found when the same OFs, generated by the observer’s movements, were replayed to a static observer. Next steps: This is inconsistent with the idea that extra-retinal information resulting from head movements is used to extract a veridical interpretation of optic flow.