Individual differences in infant fixation duration relate to attention and behavioral control in childhood

Individual differences in fixation duration are considered a reliable measure of attentional control in adults. However, the degree to which individual differences in fixation duration in infancy (0–12 months) relate to temperament and behavior in childhood is largely unknown. In the present study, data were examined from 120 infants (mean age = 7.69 months, SD = 1.90) who previously participated in an eye-tracking study. At follow-up, parents completed age-appropriate questionnaires about their child’s temperament and behavior (mean age of children = 41.59 months, SD = 9.83). Mean fixation duration in infancy was positively associated with effortful control (β = 0.20, R2 = .02, p = .04) and negatively with surgency (β = −0.37, R2 = .07, p = .003) and hyperactivity-inattention (β = −0.35, R2 = .06, p = .005) in childhood. These findings suggest that individual differences in mean fixation duration in infancy are linked to attentional and behavioral control in childhood

Ostensive signals support learning from novel attention cues during infancy

Social attention cues (e.g., head turning, gaze direction) highlight which events young infants should attend to in a busy environment and, recently, have been shown to shape infants' likelihood of learning about objects and events. Although studies have documented which social cues guide attention and learning during early infancy, few have investigated how infants learn to learn from attention cues. Ostensive signals, such as a face addressing the infant, often precede social attention cues. Therefore, it is possible that infants can use ostensive signals to learn from other novel attention cues. In this training study, 8-month-olds were cued to the location of an event by a novel non-social attention cue (i.e., flashing square) that was preceded by an ostensive signal (i.e., a face addressing the infant). At test, infants predicted the appearance of specific multimodal events cued by the flashing squares, which were previously shown to guide attention to but not inform specific predictions about the multimodal events (Wu and Kirkham, 2010). Importantly, during the generalization phase, the attention cue continued to guide learning of these events in the absence of the ostensive signal. Subsequent experiments showed that learning was less successful when the ostensive signal was absent even if an interesting but non-ostensive social stimulus preceded the same cued events

Beyond Dreams: Do Sleep-Related Movements Contribute to Brain Development?

Conventional wisdom has long held that the twitches of sleeping infants and adults are by-products of a dreaming brain. With the discovery of active (or REM) sleep in the 1950s and the recognition soon thereafter that active sleep is characterized by inhibition of motor outflow, researchers elaborated on conventional wisdom and concluded that sleep-related twitches are epiphenomena that result from incomplete blockade of dream-related cortical activity. This view persists despite the fact that twitching is unaffected in infants and adults when the cortex is disconnected from the brainstem. In 1966, Roffwarg and colleagues introduced the ontogenetic hypothesis, which addressed the preponderance of active sleep in early infancy. This hypothesis posited that the brainstem mechanisms that produce active sleep provide direct ascending stimulation to the forebrain and descending stimulation to the musculature, thereby promoting brain and neuromuscular development. However, this hypothesis and the subsequent work that tested it did not directly address the developmental significance of twitching or sensory feedback as a contributor to activity-dependent development. Here I review recent findings that have inspired an elaboration of the ontogenetic hypothesis. Specifically, in addition to direct brainstem activation of cortex during active sleep, sensory feedback arising from limb twitches produces discrete and substantial activation of somatosensory cortex and, beyond that, of hippocampus. Delineating how twitching during active sleep contributes to the establishment, refinement, and maintenance of neural circuits may aid our understanding of the early developmental events that make sensorimotor integration possible. In addition, twitches may prove to be sensitive and powerful tools for assessing somatosensory function in humans across the lifespan as well as functional recovery in individuals with injuries or conditions that affect sensorimotor function

EXPLORING THE IMPLICATIONS OF HUMOUR IN MOTHER-INFANT PLAY INTERACTIONS

Despite popular beliefs that parents should use humour to make their infants laugh to enhance infant mental health and social development, these associations have never been empirically investigated. An observational study was designed to investigate how humour in mother-infant play interactions might affect their attachment relationship. Results indicated that laughter-eliciting play activities were negatively related to infant emotional security and increases the probability of mothers engaging in disruptive frightening behaviours. However, when laughter eliciting behaviours were performed by mothers in a sensitive manner, they appeared to provide a protective effect in preventing playfully threatening games (i.e., “I’m going to get you”) from being interpreted as actually frightening and harmful. If parents engage in humorous activities with their infants, these results suggest that it is imperative that they do so sensitively or else it may harm the relationship

Word learning in the first year of life

In the first part of this thesis, we ask whether 4-month-old infants can represent objects and movements after a short exposure in such a way that they recognize either a repeated object or a repeated movement when they are presented simultaneously with a new object or a new movement. If they do, we ask whether the way they observe the visual input is modified when auditory input is presented. We investigate whether infants react to the familiarization labels and to novel labels in the same manner. If the labels as well as the referents are matched for saliency, any difference should be due to processes that are not limited to sensorial perception. We hypothesize that infants will, if they map words to the objects or movements, change their looking behavior whenever they hear a familiar label, a novel label, or no label at all. In the second part of this thesis, we assess the problem of word learning from a different perspective. If infants reason about possible label-referent pairs and are able to make inferences about novel pairs, are the same processes involved in all intermodal learning? We compared the task of learning to associate auditory regularities to visual stimuli (reinforcers), and the word-learning task. We hypothesized that even if infants succeed in learning more than one label during one single event, learning the intermodal connection between auditory and visual regularities might present a more demanding task for them. The third part of this thesis addresses the role of associative learning in word learning. In the last decades, it was repeatedly suggested that co-occurrence probabilities can play an important role in word segmentation. However, the vast majority of studies test infants with artificial streams that do not resemble a natural input: most studies use words of equal length and with unambiguous syllable sequences within word, where the only point of variability is at the word boundaries (Aslin et al., 1998; Saffran, Johnson, Aslin, & Newport, 1999; Saffran et al., 1996; Thiessen et al., 2005; Thiessen & Saffran, 2003). Even if the input is modified to resemble the natural input more faithfully, the words with which infants are tested are always unambiguous \u2013 within words, each syllable predicts its adjacent syllable with the probability of 1.0 (Pelucchi, Hay, & Saffran, 2009; Thiessen et al., 2005). We therefore tested 6-month-old infants with such statistically ambiguous words. Before doing that, we also verified on a large sample of languages whether statistical information in the natural input, where the majority of the words are statistically ambiguous, is indeed useful for segmenting words. Our motivation was partly due to the fact that studies that modeled the segmentation process with a natural language input often yielded ambivalent results about the usefulness of such computation (Batchelder, 2002; Gambell & Yang, 2006; Swingley, 2005). We conclude this introduction with a small remark about the term word. It will be used throughout this thesis without questioning its descriptive value: the common-sense meaning of the term word is unambiguous enough, since all people know what are we referring to when we say or think of the term word. However, the term word is not unambiguous at all (Di Sciullo & Williams, 1987). To mention only some of the classical examples: (1) Do jump and jumped, or go and went, count as one word or as two? This example might seem all too trivial, especially in languages with weak overt morphology as English, but in some languages, each basic form of the word has tens of inflected variables. (2) A similar question arises with all the words that are morphological derivations of other words, such as evict and eviction, examine and reexamine, unhappy and happily, and so on. (3) And finally, each language contains many phrases and idioms: Does air conditioner and give up count as one word, or two? Statistical word segmentation studies in general neglect the issue of the definition of words, assuming that phrases and idioms have strong internal statistics and will therefore be selected as one word (Cutler, 2012). But because compounds or phrases are usually composed of smaller meaningful chunks, it is unclear how would infants extracts these smaller units of speech if they were using predominantly statistical information. We will address the problem of over-segmentations shortly in the third part of the thesis

Does the pattern of fetal movement predict infant development?

Fetal Movement (FM) has been studied as a prenatal manifestation of activity level, a core dimension of many temperament theories. However, there has been little research exploring the significance of variability in the pattern of FM. The current study uses hierarchical linear modeling to compute the developmental function of FM in the third trimester. This study also examined how variability in the pattern of FM, in contrast to mean FM, predicted infant development. The following hypotheses were tested: 1. Mean FM will predict infant development at 3 and 6 months; 2. The developmental function of FM will display an inverted-U shape with significant variability; and 3. The pattern of FM will predict infant outcome at 3 and 6 months. Thirty-three mothers were asked to provide weekly counts of FM. Infant temperament, mental development, and motor development were assessed at 3 and 6 months. The best-fitting pattern describing FM was a piecewise linear function with FM increasing until 34 weeks gestation and thereafter decreasing, but variability was noted. The overall mean FM and pattern of FM were differentially associated with infant development. Higher mean FM was associated with increases in negative affect and decreases in orienting/regulation across 3 to 6 months. Mean FM also predicted infant size. The pattern of FM was related to different outcome variables. Increases in FM early and decreases in FM late in the third trimester were associated with less activity and greater emotional tone and attention at 3 months. This same pattern of FM was related to weighing more at 6 months, decreasing in extraversion from 3 to 6 months, and becoming more active from 3 to 6 months of age. The results indicate that the pattern of FM provides information about subsequent development that is different from mean FM. Whereas mean FM was associated with aspects of difficult temperament, the pattern of FM predicted more positive outcomes. These findings suggest that the pattern of FM may be useful as a prenatal assessment of postnatal development

Multi-Sensoriality In Language Acquisition: The Relationship Between Selective Visual Attention Towards The Adult’s Face And Language Skills

Introduzione Le componenti uditive e visive del linguaggio offrono al bambino informazioni cruciali per il processamento del parlato. L’abilità del bambino di integrare informazioni da diverse fonti multimodali (audio e visive) e di focalizzare l’attenzione sui segnali rilevanti presenti nell’ambiente circostante (selective visual attention) sono aspetti importanti che influenzano le prime fasi di acquisizione di una lingua. Alcuni recenti studi hanno ipotizzato e testato la relazione tra attenzione selettiva visiva verso specifiche aree del volto parlante (occhi o bocca) e le abilità linguistiche di bambini nei primi anni di vita. Molti ricercatori hanno speculato su come questa relazione potesse essere mediata dal livello di expetise del bambino, a livello linguistico (language expertise hypothesis), ma nessuno studio, fin ad ora, ha cercato di approfondire questa ipotesi, andando ad investigare le abilità linguistiche dei bambini usando misure di linguaggio spontaneo. Altri studi, hanno cercato di esplorare come diversi comportamenti attentivi verso specifiche aree del volto (occhi o bocca) fossero correlati alle abilità linguistiche concomitanti o longitudinali dei partecipanti. In molti casi, i risultati di questi studi hanno confermato l’esistenza di relazioni significative tra attenzione visiva selettiva e abilità linguistiche al tempo dell’esperimento o qualche mese dopo. Obiettivi L’obiettivo generale di questa tesi è quello di esaminare il fenomeno dell’attenzione selettiva visiva verso il volto e la sua relazione con lo sviluppo del linguaggio sia in un setting di laboratorio sia in un contesto naturalistico. In particolare, tre sono gli obiettivi specifici: - il primo obiettivo specifico è quello di sintetizzare e analizzare i fattori individuati dalla letteratura di riferimento che possono determinare diversi patterns di attenzione selettiva visiva nei bambini durante un compito audiovisivo. Ed in particolare, descrivere come la letteratura spiega questi patterns in relazione agli aspetti dello sviluppo del linguaggio; 8 - il secondo obiettivo specifico è quello di analizzare sperimentalmente l’attenzione selettiva visiva del bambino verso specifiche aree del volto (occhi e bocca) durante un compito di esposizione audiovisivo. In particolare, lo studio è volto ad indagare due aspetti. Il primo aspetto riguarda l’età e la condizione linguistica (esposizione ad una lingua nativa vs una lingua non nativa) dei partecipanti e come queste influenzano l’attenzione selettiva visiva verso specifiche aree del volto. Il secondo aspetto riguarda l’esplorazione dell’esistenza di una correlazione tra comportamento attentivo dei bambini la produzione vocale al tempo dell’esperimento e all’ampiezza del vocabolario tre mesi dopo; - il terzo obiettivo specifico è quello di capire se l’attenzione a volti o altre parti della scena visiva (oggetto, altre parti della stanza) è influenzato o spigato dalle abilità vocali del bambino al tempo del task e se gli episodi di fissazione al volto adulto possono essere predetti da specifiche proprietà fonologiche e semantiche del parlato del bambino. Metodo Per quanto concerne il primo studio, una rassegna sistematica della letteratura è stata condotta esplorando quattro fonti bibliografiche e usando specifici criteri di inclusione per selezionare la letteratura scientifica di interesse. Per quanto riguarda il secondo studio, i movimenti oculari verso un volto parlante la lingua nativa (Italiano) e non-nativa (Inglese) di 26 bambini tra i 6 e i 14 mesi sono stati tracciati usando l’eye tracker. Due gruppi sono stati creati sulla base dell’età (G1, M = 7 mesi, N = 15 bambini; G2, M = 12 mesi, N = 11 bambini). Ogni competenza linguistica del bambino è stata valutata due volte, al tempo dell’esperimento, attraverso l’osservazione diretta e tre mesi dopo, attraverso il MB-CDI. Due gruppi sono stati creati sulla base della produzione vocale dei bambini (vocalizzi pre-canonici, babbling, parole) attraverso un latent class cluster analysis: una classe vocale “alta” (percentuale di babbling e parole più alta) e una classe vocale “bassa” (percentuale maggiore di produzioni pre-canoniche). Per quanto concerne il terzo studio, il comportamento attentivo di 29 bambini tra i 12 e i 19 mesi è stato esplorato utilizzando sia una videocamera stazionaria 9 (posizionata di fronte alla diade) e una go-pro (posizionata sulla fronte del caregiver di riferimento) durante un semplice task linguistico (single object task). Durante il task i bambini sono stati esposti ad un set di stimoli audiovisivi, parole vere e non parole, scelte sulla base dei report dei genitori e sulle risposte al MB-CDI. Il comportamento attentivo dei bambini è stato codificato offline, secondo per secondo per un totale di 116 sessioni. La codifica ha riguardato specifiche aree di interesse (il volto, l’oggetto, o altre parti della stanza). La produzione vocale per ogni bambino è stata quantificata usando LENA e le produzioni del bambino (vocalizzi pre-canonici, babbling, parole) durante un periodo di gioco con la mamma sono state trascritte foneticamente. Risultati La rassegna sistematica della letteratura (Capitolo 2) ha portato all’identificazione di 19 articoli. Alcuni dei quali volti a chiarire il ruolo giocato da diversi fattori nel spiegare diversi patterns attentivi. Altri interessati ad indagare la correlazione tra l’attenzione selettiva visiva verso specifiche aree del volto alle competenze linguistiche o sociali dei partecipanti, aprendo le porte a diverse linee interpretative. Il primo studio empirico (Capitolo 3) ha messo in luce che i bambini italiani con età superiore ai 12 mesi, mostrano maggiore interesse verso l’area della bocca, specialmente quando esposti alla lingua nativa. Questo è in accordo con la recente letteratura, ma contrasta con la language expertise hypotesis (secondo la quale bambini attorno all’anno di età dovrebbero spostare il focus attentivo dalla bocca agli occhi). Il secondo risultato emerso in questo lavoro empirico riguarda l’interesse verso l’area della bocca per i bambini che hanno maggiori livelli di produzione in termini di babbling e parole al tempo dell’esperimento. Il terzo risultato riguarda l’associazione positiva tra il comportamento attentivo verso la bocca ed il vocabolario espressivo dei bambini misurato tramite questionario (MB-CDI) tre mesi dopo l’esperimento. Dal secondo studio empirico (Capitolo 4) emerge una differenza significativa in termini di tempo attentivo verso il volto adulto tra i bambini del gruppo linguistico “alto” e “basso” durante un task condotto in un contesto naturalistico. 10 In particolare, da questo studio emergono due risultati interessanti: il primo è che i bambini che producono forme vocaliche più avanzate (babbling e parole) guardano di più verso il volto adulto, specialmente quando esposti alle non-parole. Il secondo riguarda l’esistenza di una relazione significativa tra gli episodi di fissazione al volto e le abilità vocaliche del bambino al tempo del task (vocalizzi pre-canonici, babbling e parole). In particolare, emerge che la quantità di babbling prodotto ha un ruolo nel predire gli episodi di fissazione al volto durante il task, sia per le parole sia per le non parole. Conclusioni Diverse ipotesi linguistiche e sociali sono state avanzate per spiegare le differenze emerse dalla rassegna della letteratura in relazione al fenomeno dell’attenzione selettiva visiva. Gli studi empirici presentati in questa tesi hanno portato due contributi originali in quest’ambito di ricerca. Da un lato, i nostri risultati confermano l’idea che la bocca e, più in generale, il volto forniscono segnali visivi cruciali nelle prime fasi di acquisizione del linguaggio. Dall’altro lato, i risultati hanno messo in luce che la conoscenza linguistica e le abilità linguistiche dei partecipanti aiutano a spiegare diversi comportamenti attentivi. In altre parole, è possibile dire che l’attenzione selettiva ai volti, o a specifiche aree di questi, è spiegata dalle conoscenze e abilità linguistiche attuali dei partecipanti.Introduction Speech is the result of multimodal or multi-sensorial processes. The auditory and visual components of language provide the child with information crucial to the processing of speech. The language acquisition process is influenced by the child’s ability to integrate information from multimodal (audio and visual) sources and to focus attention on the relevant cues in the environment; this is selective visual attention. This dissertation will explore the relationship between children’s selective visual attention and their early language skills. Several recent studies with infant populations have hypothesised or tested the relationship between children’s selective visual attention towards specific regions of the talking face (i.e., the eyes or the mouth) and their language skills. These studies have tried to show how concomitant or longitudinal language skills can explain looking behaviours. In most cases, these studies have speculated on how this relationship is mediated by the child’s level of language expertise (this is known as the language expertise hypothesis). However, no studies until now, to the best of our knowledge, have investigated the child’s linguistic skills using spontaneous language measures. Aims The dissertation has one broad aim, within which there are three particular aims. The broad aim is to examine the phenomenon of selective visual attention toward the face in both a laboratory and a naturalistic setting, and its relationship with language development. The three particular aims are as follows. The first aim is to synthesise and analyse the factors that might determine different looking patterns in infants during audiovisual tasks using dynamic faces; it describes how the literature explains these patterns in relation to aspects of language development. The second aim is to experimentally investigate the child’s selective visual attention towards a specific region of the adult’s face (the eyes and the mouth) in a task using the eye-tracking method. In particular, the study will explore two 12 questions: First, how do age and language condition (exposure to native vs non-native speech) affect looking behaviour in children? Second, are a child’s looking behaviours related to vocal production at the time of the experiment and to vocabulary rates three months later, and if so, how? The third aim is to understand whether selective attention towards the face or other parts of the visual scene (i.e. the object or elsewhere) is influenced or explained by the child’s vocal skills at the time of the task. And can the episodes of fixation towards the adult’s face be predicted by specific phonological and semantic properties (i.e., pre-canonical vocalisations, babbling, words) of the child’s speech? Method For the first study, a systematic review of the literature was conducted, exploring four bibliographic databases and using specific inclusion criteria to select the records. For the second study, eye movements towards a dynamic face (on a screen), speaking in the child’s native language (Italian) and a non-native language (English), were tracked using an eye-tracker in 26 infants between 6 and 14 months. Two groups were created based on age (G1, M = 7 months, N = 15 infants; G2, M = 12 months, N = 11 infants). Each child’s language skill was assessed twice: at the time of the experiment (through direct observation, Time 1) and three months later (through MB-CDI, Time 2). Two groups were created, based on the child’s vocal production (Time 1, latent class cluster analysis): a high class (higher percentage of babbling and words) vs a low class (higher percentage of pre-canonical vocalisations). For the third study, the looking behaviour of the same 29 children between 12 and 19 months was tracked, using both a stationary video camera and a head-mounted camera on the mother’s head during a single object task. During the task, children were exposed to a set of audiovisual stimuli, real words and non-words, chosen based on the parents’ reports and their MB-CDI answers. The child’s looking behaviour was coded offline second-by-second for a total of 116 sessions. The coding relates to specific areas of interest, i.e., the face, the object or 13 elsewhere. The vocal production of each child was quantified using a LENA device, and their speech during a play period with their mothers was transcribed phonetically. Results The systematic search of the literature (Chapter 2) identified 19 papers. Some tried to clarify the role played by audiovisual factors in support of speech perception (provided by looking towards the eyes or the mouth of a talking face). Others related selective visual attention towards specific areas of the adult’s face to the child’s competence in terms of linguistic or social skills, this leads to correspondingly different lines of interpretation. The first empirical study (Chapter 3) shows that Italian children older than 12 months displayed a greater interest in the mouth area, especially when they were exposed to their native language. This accords with the more recent literature but contrasts with the language expertise hypothesis. The second significant result of Chapter 3 is that children who had a higher level of production in terms of babbling and words at the time of the experiment looked more towards the mouth area. The study reported in Chapter 3 also demonstrated a positive association between the child’s looking to the mouth and their expressive vocabulary as measured (using the MB-CDI) three months after the experiment The second empirical study (Chapter 4) shows a significant difference in the looking time towards the adult’s face between children with low- and high-vocal production in a naturalistic setting. More specifically, from this study, we find two things. Firstly, we found that the children who produced more advanced vocal forms (higher amount of babbling and word production) looked more towards the adult’s face, especially when exposed to non-words. Secondly, that a significant relationship exists between the episodes of fixation towards the adult’s face and the child’s vocal skills (i.e., pre-canonical vocalisations, babbling, words); babbling productions predicted the episodes of face fixation in the task as a whole, for both words and non-words. 14 Conclusion Linguistic and social-based hypotheses attempting to explain the differences in the selective visual attention phenomenon emerged from the literature review. The empirical studies presented in this thesis bring two original contributions to this research field. First, our findings reinforce the idea that the mouth and, more generally the face, provide crucial visual cues when acquiring a language. Secondly, our results demonstrate that language knowledge and language skills at the time the child was observed significantly help to explain different looking behaviours. In other words, we can conclude that each child’s attention to faces is shaped by their own linguistic characteristics

Grounding Mental Representations in a Virtual Multi-Level Functional Framework

According to the associative theory of learning, reactive behaviors described by stimulus-response pairs result in the progressive wiring of a plastic brain. In contrast, flexible behaviors are supposedly driven by neurologically grounded mental states that involve computations on informational contents. These theories appear complementary, but are generally opposed to each other. The former is favored by neuro-scientists who explore the low-level biological processes supporting cognition, and the later by cognitive psychologists who look for higher-level structures. This situation can be clarified through an analysis that independently defines abstract neurological and informational functionalities, and then relate them through a virtual interface. This framework is validated through a modeling of the first stage of Piaget’s cognitive development theory, whose reported end experiments demonstrate the emergence of mental representations of object displacements. The neural correlates grounding this emergence are given in the isomorphic format of an associative memory. As a child’s exploration of the world progresses, his mental models will eventually include representations of space, time and causality. Only then epistemological concepts, such as beliefs, will give rise to higher level mental representations in a possibly richer propositional format. This raises the question of which additional neurological functionalities, if any, would be required in order to include these extensions into a comprehensive grounded model. We relay previously expressed views, which in summary hypothesize that the ability to learn has evolved from associative reflexes and memories, to suggest that the functionality of associative memories could well provide the sufficient means for grounding cognitive capacities

Tutoring in adult-child-interaction: On the loop of the tutor's action modification and the recipient's gaze

Pitsch K, Vollmer A-L, Rohlfing K, Fritsch J, Wrede B. Tutoring in adult-child-interaction: On the loop of the tutor's action modification and the recipient's gaze. Interaction Studies. 2014;15(1):55-98.Research of tutoring in parent-infant interaction has shown that tutors - when presenting some action - modify both their verbal and manual performance for the learner (‘motherese’, ‘motionese’). Investigating the sources and effects of the tutors’ action modifications, we suggest an interactional account of ‘motionese’. Using video-data from a semi-experimental study in which parents taught their 8 to 11 month old infants how to nest a set of differently sized cups, we found that the tutors’ action modifications (in particular: high arches) functioned as an orienting device to guide the infant’s visual attention (gaze). Action modification and the recipient’s gaze can be seen to have a reciprocal sequential relationship and to constitute a constant loop of mutual adjustments. Implications are discussed for developmental research and for robotic ‘Social Learning’. We argue that a robot system could use on-line feedback strategies (e.g. gaze) to pro-actively shape a tutor’s action presentation as it emerges