This thesis describes three behavioral and one fMRI study in which the underlying psychological and neural mechanisms of stay/leave decision making in both a nonsocial and social context were investigated and compared. In Study 1A and 1B participants played a social or nonsocial version of a novel economic game in which participants were dependent on a social partner or nonsocial resource to increase their monetary outcomes. Both actual and expected reward probability of social partners and nonsocial resources positively affected the time participants decided to stay with a specific social partner or nonsocial resource. The effect of expected reward probability on staying times was much more pronounced in the nonsocial context. In Study 2, Reinforcement Learning models were fitted to participant's choices in a social and nonsocial version of the 4-armed bandit task in which prior beliefs about partners or resources were manipulated. The effects of Study 1B were replicated. Furthermore, it was found that participants weight expectancy-consistent and inconsistent new observations differentially when learning about both social partners and nonsocial resources. Participants had generally higher learning rates in the social than nonsocial context but this was not the case when prior beliefs were not induced. In Study 3, participants played a social and nonsocial version of the 4-armed bandit task while undergoing fMRI. Increased activation in caudate nucleus was associated with stay decisions in a social rather than nonsocial context; and the dorsal anterior cingulate cortex showed differential activation as a function of stay and leave decisions and this pattern was reversed in the nonsocial and social context. Interpretation of these results are discussed in light of a fundamental need to belong that motivates people to stay with social partners specifically and resist against breaking social connections.

The experiments reported in the thesis investigate the nature of word stress and its lexical representation. Focusing on Italian, I considered two research questions: How is lexical stress represented? How does this representation intervene in perceiving or producing a word? Italian is a polysyllabic language with free-stress position: Stress may appear on one of the last three-syllables (e.g., TAvolo, ‘table’, paROla, ‘word’, coliBRI, ‘hummingbird’, capitals indicate stress) and its position is not predictable by rules. Moreover, there is a large asymmetry in the distribution of the stress patterns, with about 80% of words bearing stress on the penultimate syllable (e.g., paROla, ‘word’). On the assumption that stress is a lexical feature and that the stress pattern of a word is part of the knowledge stored in the lexicon, three studies were designed in which a priming paradigm and a visual word paradigm were used. Specifically, we investigated lexical stress in two domains, i.e., spoken-word recognition (Chapter 2) and reading aloud (Chapters 4 and 5). The results shed new light on the nature of the stored prosodic knowledge about lexical stress and on what extent processing of lexical stress is similar in spoken-word recognition and reading aloud. In synthesis, the empirical evidence indicates that lexical stress is part of the abstract prosodic knowledge stored in the lexicon: It pertains to the suprasegmental level of word representation and it is dissociable from the information pertaining to the segmental level.

The present thesis investigates the graphemic stage of the spelling process. Aim of thesis is to study the sub-processes occurring at the orthographic working memory level and the interaction between graphemic representations and working memory that holds these representations active during spelling. Chapter 1, after a brief description of the two-routes spelling model adopted in this research, deals with, presenting neuropsychological evidences, some of the most important issues about the relations between the different levels of elaboration that are engaged in the spelling process. Final part of this chapter is dedicated to the review of the neuropsychological researches regarding the structural organization and the processing of the orthographic representation. Chapter 2 reports the cases of GSI and CRI, two dysgraphic subjects with a selective deficit for consonants and a graphemic buffer disorder (GBD), whose spelling patterns are consistent with the hypothesis that their deficits affect different properties of orthographic working memory: temporal stability for GSI and representational distinctiveness for CRI. Their performance on spelling task demonstrate two things: first, GBD is not a homogeneous deficit because different sub-processes, involved in graphemic buffering, can be selectively affected by cerebral damage; second, different patterns of GSI and CRI arise from interaction of consonant representation and WM properties, both impaired in these subjects. Chapter 3 reports the case of a third dysgraphic subject, PPO, with a selective disorder for consonants but whose spelling picture was not identifiable as a clear GBD. Spelling pattern of this subject, quite different from those of both subjects of Chapter 2, demonstrates that the internal structure of orthographic representation, holding at working memory level, can be selectively impaired in the absence of working memory deficit. Moreover, PPO’s results on spelling task confirm the role of temporal stability and representational distinctiveness in the spelling and the interaction between representations and WM. Finally, Chapter 4 summarizes all the presented results and discusses the implications.

The study of the interactions between olfaction and the decision making processes has mainly focused on the investigation of what is considered the most useful odor to disperse in the air to drive the consumers' choices to prefer a product rather than another one. Despite the fact that some studies showed the existence of associations between odors and prosocial behavior, much less data are available on the links between olfaction and donation in favor of public goods. Thus, the main purpose of the series of experiments described in this thesis is precisely that to shed some light on the investigation of the nature of pleasant odor-decision and on the chemosignal-decision associations. In order to achieve this, the presence of an odor and the congruence between odor and decision task has been manipulated, and the decision to donate has been tested in different domains. Therefore, in the first series of experiments, we manipulated the presence of an ambient pleasant odor, expecting that the congruent stimuli sharing the more stable association odor-concept, would have resulted in an overall increase in the WTC (willingness to contribute) and WTP (willingness to pay) in the decision to donate in favor of a public good. The results confirmed the existence of an association between the olfactory stimulus congruence and the amount donated in favor of a public good. Interestingly, this effect is confirmed in both hypothetical and real decision settings. Moreover, the stimulus modality was manipulated presenting congruent olfactory or visual stimuli. Our findings confirmed the preferential link between olfaction and cognitive processes and showed higher donations in the olfactory setting (compared to the visual one). The existence of associations between odors and words are examined to know if the odors could semantically drive cognitive processes different from decision making. The results confirmed the existence of an association between the olfactory stimulus pleasantness and the performance in a lexical decision task (LDT). Thus, this effect is mediated by the presence of a pleasant odor and not by the semantic congruence between odor and the presented words. Moreover, the visual modality tend to worsen the LDT performance even if the visual stimulus was semantically congruent with the word presented. Finally, even though the semantic link appears to be crucial for cognitive processes such as decision, it seems not so important for memory and linguistic processes involved in the LDT. The second series of studies involved the presence of chemosignal, expecting that the congruity between stimulus and decision (the chemosignal used is AND, known as the best candidate to be considered a human chemosignal) would have resulted in an overall increase in amount of money donate to unknown persons during Dictator and Trust Game. The results confirmed the existence of an association between the chemosignal stimulus presence (and its olfactory experience) and the amount donated, and a mediation effect due to the positive mood (in presence of AND) especially in females and with high AND concentration.

Standard economic models explain decision making under risk as a utility maximization process. Developments in cognitive psychology and neuroeconomics showed the volatility of such conceptualization highlighting human bounded rationality and discussing the role of decision maker’s affective state (basic reactions to any emotionally charged event) in cognitive evaluation of risk (risk as feeling). In particular, an affective-based evaluation of choice options may determine whether decision maker’s behavior will be risk averse or risk seeking. Evidence indicates that affective reactions carry over significant information about the goodness of certain choice options directly influencing risk taking behavior. Affective influences on decisions may be directly associated with the evaluation of the choice options and the anticipation of future outcomes (integral affect) or may be associated with stimuli or event unrelated to the decision at hand, for example contextual factors or environmental cues (incidental affect). A classic advertisement strategy, such as a smiling face presented in association with a good, is an example of contextual affective manipulation. Research shows that experiencing a positive affective state may lead to risk aversion behavior while negative affect may lead to risk seeking. However, previous studies mostly adopted a valence-based approach to the study of affect ignoring its multidimensional nature. In particular, the role of arousal has been largely neglected. Recent studies showed that emotional states with the same valence may have opposite consequences on risk taking. Therefore, the main purpose of the series of studies described in this dissertation was to investigate the effect of inducing incidental affective states at high and low levels of negative arousal or positive arousal on preferences for monetary options varying in risk. Research shows that elevated arousal is associated with cognitive depletion, increased sensitivity to rewards, immediate gratification, less resistance to temptation. Therefore, we hypothesized that affective states characterized by high levels of arousal might increase preferences for the riskier option. We further predicted that including arousing stimuli as contextual factor of a decision scenario would capture individual attention interfering with information processing of risk. In order to achieve this goal, in a first series of experiments we asked participants to make choices between couples of two-outcomes lotteries with the same expected value but different risk. Arousal was manipulated by presenting participants with visual stimuli (IAPS pictures) varying in the level of arousal (high or low) keeping the valence unvaried (negative or positive). By adopting the technique of contextual priming, participants were simultaneously exposed to stimuli (the lotteries) and the contextual factor (the arousing/unarousing image). An effect of arousal on predicting risky choice was found. Probability of selecting the riskier lottery was higher when an arousing stimuli (unpleasant or pleasant) was included as part of the decision context. In some cases, positive arousal was found to interact with gender: risk taking was higher in males than females when a pleasant arousing cue was presented. In a second series of studies, participants performed the same task and, by using an eye tracker, eye fixations and looking times were recorded. The predicted effect of arousal on attention was found. Participants spent more time looking at the arousing image (unpleasant or pleasant). This result is in line with arousal theories which correlate the level of arousal to attention allocated to the arousing stimuli. Furthermore, participants seemed to process less risky information (as indicated by decreased looking times toward the riskier option) when the arousing stimuli was contextually presented, as opposed to when the unarousing stimuli was presented.

The study of cross-modal and cross-dimensional associations in non-synesthetes has become an increasingly hot topic in recent times (see Spence, 2011, for a review). Despite the many examples of associations between shape/color-stimuli on one hand and stimuli of different sensory nature on the other hand, little is known about the way shape and color are interrelated with each other. The purpose of our research was to test whether non-synesthetes also exhibit systematic associations between these two different dimensions of the visual domain, that is, shape and color. Furthermore, our study also relates to art, and in particular to Kandinsky’s theory on shape-color correspondences (1912, 1926), which could be tested indirectly. The project consisted of six experiments, some of them (Experiments 1-3 and 6) carried out in the Experimental Psychology Labs at the University of Trento under the supervision of Prof. Liliana Albertazzi, and the others (Experiments 4-5) carried out in the Visual Perception and Aesthetics Lab at the University of California Berkeley, under the supervision of Prof. Stephen E. Palmer. Experiment 1 provided the first evidence that people tend to match certain hues to certain simple geometric shapes. The strongest relations were found between the triangle and yellows, and the circle and square with reds, confirming only in part Kandinsky’s artistic findings. Experiment 2 replicated the results of Experiment 1 with a different group of participants and showed that the pattern of shape-color associations that previously emerged was independent of a shape’s size, area/perimeter, and stability. Experiment 3 examined the relation between parts of shapes (angles) and hues, also in order to assess if the choice of a hue to be matched with a given shape could be partly driven by its angles. In the remaining experiments (4-5), we extended the previous studies to color dimensions other than the hue, and to an even wider variety of shapes and shape-features. The shape-features studied included pointedness, intersections, symmetry-axes, concavities, and the number of generating-points. We found that specific shape-features of line-shapes (Experiment 4) or closed geometric shapes (Experiment 5) influence specific color attributes (saturation, lightness, redness/greenness, and yellowness/blueness) of the associated colors. Our results also suggested that shape-color associations may be mediated, in part, by emotions; indeed people tend to match colors and shapes that have similar emotional associations (e.g., angry colors are matched to angry shapes). Finally, Experiment 6 assessed in an exploratory way the association between words related to abstract concepts and hues. Altogether, additional examples of associations in the non-synesthetic population were reported. We suggest that this new trend of research, at large, could improve the study of human perception and cognition, guide the search for neural correlates, as well as find possible applications in a variety of disciplines, including ergonomics, art, and design.

In this thesis we deal with the role of the commutative property in the organization of the memory that encodes the knowledge about two arithmetic operations: multiplication and addition. Despite its relevance in arithmetic the commutative property has been largely neglected. This theoretical underestimation of the order of the operands and of the cognitive processing of commutative property is likely due to the lack of strong empirical evidences. In this thesis we provide new and clear empirical evidences of a operands-order effects. Five experiments were conducted by using various methodologies. Our results indicate that commutative pairs are processed differently for the two operations. For additions, we found an effect of the order of the operands. Namely, the problems in which the first operand is the larger (e.g., 7+4) were solved faster than the commuted problems (e.g., 4+7). For multiplication, we found an extremely surprising result that can not be predicted by any of the current models of arithmetical cognition, that is an interaction between the order of the operands and the size of the problem. Namely, for large multiplications (both operands larger than 5) the problems in which the first operand is the smaller (e.g., 7×8) were solved faster than the commuted problems (e.g., 8×7); for small multiplications (both operands smaller than 5) and medium multiplications (one operand smaller and the other larger than 5) the problems in which the first operands is the larger (e.g., 3×4, 7×3) were solved faster than the commuted problems (e.g., 4×3, 3×7). For both operations the relevant role of the order of the operands (and its interaction with size for multiplication) in the processing of the problems is also confirmed by a ERPs study. This results are interpreted as the evidence that the arithmetic facts memory is organized by the commutative property. More precisely, we propose to interpret the effects we found as due to the interaction of two factors that shape this memory according to the commutativity: (1) the order of acquisition of the commuted pairs and (2) a reorganization of the memory due to the use of non-retrieval procedures that privilege one of the two orders of the operands. Clearly, further researches are needed in order to better understand the relation between arithmetic facts memory and the commutative property. However, our result have showed a new effect that can usefully be used to investigate how the cognitive system encode, represent and process the arithmetical knowledge.

In daily life, we are immersed in a continuous flow of stimuli targeting each of our different senses. Far from being independently processed, accumulating evidence has been widely documented by studies showing that stimuli from different modalities largely interact. However, despite the increasing interest, the interpretations of the results of experiments studying multisensory interaction are still controversial and the underlying mechanisms remain broadly unknown. The aim of this thesis is to investigate the interactions that occur between the senses of audition and touch. Audiotactile interactions have been far less studied than the ones existing between other modality pairings. Maybe because they go often unnoticed though being well present in many everyday life situations. This thesis focuses mainly on two aspects that concern interactions: understanding the impact of the relative saliency between the stimuli and investigating the mechanism behind perceptual integration. These questions are addressed respectively in two studies conducted by means of magnetoencephalography. The thesis is structured as following: in chapter 1, I provide the theoretical background to my scientific questions. A brief synthesis of the two main studies is presented in chapter 2. The two studies are entirely reported under the form of manuscripts in chapter 4. Finally, in appendix a behavioral study that investigates spatial aspects of AT interactions is reported. Although the results of this study are of pertinence of the project, given the preparatory character and the preliminary state of the study we decided to show them in the appendix rather than include them in the main body of the thesis.

The great influence of mass technologies has changed our writing modality that is moving from the traditional use of pen and paper to the domain of keyboards and recently to touchscreen tools, both in everyday life and in educational contexts. The digitalization of writing and of the texts we write, but also the ubiquity of digital technologies, should encourage a deeper understanding of the implications of the physical and sensorimotor changes in writing. It is reasonable to think that the motor-perceptual differences between different writing modalities can lead to different cognitive performances in linguistic tasks, depending on the writing movement that has to be performed but also on the experience that we have with this movement. In this work, I take into account the role of tangible devices for writing and their different haptic affordance, rarely considered in the study of language, in general, and of writing, in particular. To do so I analyzed different behaviors while we use different writing technologies and discuss the findings from a cognitive science point of view. The general aims of this thesis consists in establishing possible cognitive entailment of different types of writing modalities, in explicating their role in other linguistic tasks and in evaluating the possible implication on daily life and education. The thesis is presented like a collection of papers, results of my research activity and experiences during my participation in the doctoral school. I divided my work in three separate chapters in which different research points of views are analyzed, different experimental procedures are used and different technological devices for writing are tested. Chapter 1 present a study aimed at investigating whether technologically mediated linguistic performance reflects cross-modal interaction and whether it is modulated by the writing technology used, specifically a touchscreen and a keyboard. Chapter 2 comprises a set of studies dedicated to investigate whether it is possible that a strong experience in typing influences our linguistic abilities. Furthermore, typing and mobile typing are compared testing if the two writing modalities share the same motor behaviors. Mobile technologies are also the argument of Chapter 3 in which I present two theoretical papers dedicated to the potential of these devices for learning, in general, and for second language learning, in particular.

This thesis investigated the crossmodal interactions occurring between hearing and touch. Chapters 1 to 6 present the background to this topic and an introduction to the underlying mechanisms of crossmodal perception. Chapter 1 provides a historical overview on the pioneering studies in this issue, whereas in the successive ones the main behavioural evidence on is described. Specific aspects are presented across the chapters, with Chapter 2 presenting the studies using detection/discrimination tasks, intensity tasks, or investigating texture perception or crossmodal sensory illusions and pseudosynaesthetic correspondences. In the subsequent chapters, more specific aspects are taken into consideration, such as the temporal (Chapter 3) and the spatial (Chapter 4) constraints characterizing audiotactile interactions. In Chapter 5, special attention is given to the neural substrates of the audiotactile sensory interplay, in both humans and monkeys. Since there is considerable evidence showing that visual deprivation influences how touch and hearing interact, Chapter 6 will be devoted to explore this topic in more detail. The following chapters present the experimental studies designed to empirically investigate different aspects of audiotactile interactions. Chapter 7 contains experimental studies examining the potential existence of a sensory dominance between hearing and touch, by investigating different portions of the peripersonal space and/or spatial arrangement of the stimuli. Chapter 8 is focused on evaluate the capability of humans in matching the frequency pattern of auditory, tactile and crossmodal stimuli. The spatial factors affecting audiotactile interactions will be explored in Chapter 9, by evaluating how the perception of apparent motion in one modality is biased by the presentation of apparent moving stream in the other modality. The investigation of crossmodal compatibility effects is the topic of Chapter 10. Since visual deprivation has been proved to influence how touch and hearing interact, the last chapter (Chapter 11) will be devoted to compare either spatial or temporal perception, as well as the construction of frames of reference for tactile processing - in relation with auditory stimulation- in blind and sighted individuals.