The importance of "scaffolding" in clinical approach to deafness across the lifespan

Throughout the present work of thesis, the concept of scaffolding will be used as a fil rouge through the chapters. What I mean for “scaffolding approach”, therefore, is an integrated and multidisciplinary clinical and research methodology to hearing impairments that could take into account persons as a whole; an approach that needs to be continuously adapted and harmonized with the individuals, pursuant to their progress, their limits and resources, in consideration of their audiological, cognitive, emotional, personal, and social characteristics. The following studies of our research group will be presented: A study (2020) designed to assess the effects of parent training (PT) on enhancing children’s communication development (chapter two); Two studies of our research group (2016; 2020) concerning variables influencing comprehension of emotions and nuclear executive functions in deaf children with cochlear implant (chapter three and chapter four) In chapter five a presentation and description of our Mind-Active Communication program, main topics and aims, multidisciplinary organizations of group and individual sessions with a description of used materials and methodology is given. Finally, a preliminary evaluation to explore the use of this multidisciplinary rehabilitative program on quality of life, psychological wellbeing, and hearing abilities in a sample of cochlear implanted elderly persons is reported

Aging Effects on Perception of Parkinsonian and Normal Geriatric Speech

Parkinson disease (PD) is frequently associated with speech and voice deficits, including changes in phonatory, articulatory, speech intelligibility, and prosodic aspects (Spencer, Sanchez, McAllen, & Weir, 2010). Prior studies have investigated listener perception of speech produced by speakers with PD using structured speech tasks such as word repetitions, sentence readings, and passage readings (i.e., Cheang & Pell, 2004; Dagenais, 2011). However, research has also indicated the need for studies with more naturalistic speech stimuli, including monologues, to determine perceptual abilities of different listener groups. Limited studies have examined perception by different listener groups for monologues produced by individuals with PD. The purpose of this study was to investigate aging effects among different listener groups during perception of monologues produced by individuals with PD and age- and gender-matched neurologically normal speakers (NS). The study included three listener groups (younger, middle-aged, older-aged adults). Speakers included five individuals with PD and five NS. All speakers produced a short monologue on a topic of interest. The three listener groups listened to the recorded monologues and completed a visual analog scale (VAS) to rate seven speech variables (including pitch, pitch variability, loudness, speech rate, pauses, understandability, and perception of effort) for the two speaker groups. Among the seven variables, results indicated that listener groups rated understandability and perception of effort significantly differently for individuals with PD and NS. All three listener groups rated the understandability for speakers with PD to be significantly lower than NS. However, the listener groups did not have any significantly different ratings for the remaining five variables including pitch, loudness, and speech rate. In addition, when the listener groups were compared amongst themselves, there were no significant aging effects among the groups for perception of monologues. Findings from the study provide evidence for similar perception among different aged normal listener groups for perception of monologues by individuals with PD and neurologically normal speakers.Communication Sciences & Disorder

Capturing the Attention of Caregivers: Variability in Infant Vocalizations

The effect of variability in infant vocalizations on potential caregivers’ heart rate variability (HRV), facial expressions, and subjective ratings on emotional reactions and desire to approach the baby was examined in an evolutionary context. Recordings of non-canonical, canonical, fussing, and crying vocalizations were utilized to elicit physiological and self-reported reactions from sixty participants. Breastfeeding mothers, non-mothers at high estradiol point in menstrual cycle, non-mothers at low estradiol point in menstrual cycle, fathers, and non-fathers were included in the study. Participants wore Polar RS800 heart rate monitors, were video recorded for facial expression analysis, and filled out 11 point self-rating forms on emotional reactions to the infant vocal stimuli. It was expected that participants would show higher HRV for the canonical vocalizations as compared to non-canonical, fussing and crying vocal stimuli. Overall HRV as measured by SDNN (standard deviation of NN, or “normal-to-normal” interbeat intervals), was highest for the recorded babbling, however these differences were not significant. Most raters considered crying and fussing to be strong indicators of a need for interaction. Participants showed the greatest percentage of happy facial expressions (evaluated via analysis of video recordings) and also self-reported the babbling vocalizations high on “happiness” and “most liked”, as predicted. Although the predicted directions for the differences between mothers and non-mothers at two different assumed estradiol levels in menstrual cycle were not significant, breastfeeding mothers did show higher facial expressions of happiness while listening to the babbling stimuli, gave higher scores of self-rated sadness when listening to crying, and rated their irritation levels lower and the desire to pick up the baby higher for the fussing stimuli. The square root of the mean squared difference of successive NN intervals were significantly higher in fathers than non-fathers while listening to the babbling stimuli. Fathers had significantly higher self-reported happiness levels and higher scores towards the “most liked” end of the rating scale for the babbling stimuli. The results are discussed within an evolutionary framework considering the potential influence of parental selection of vocal behaviors, an attraction to complexity of sounds across species, as well as the possible influence of hormones on potential caregivers’ responses to infant needs

Learning instructional communication skills in peer collaborative problem solving : a case of moving referent.

The present work is an attempt to combine two traditions of communication study: referential communication approach and sociolinguistic approach. The purpose was to examine how children ages 5 and 7 years learn to give instructions to each other in a peer collaborative problem solving situation. In an effort to identify interaction patterns and possible developmental progressions, various coding and categorization schemes were developed to analyze the processes of: negotiation of themes, establishing a common perspective toward the task, co-constructing messages and shared names. A comparison was made between the children\u27s development of spatial terms for a stationary referent and a moving referent. The analysis shows that 7-year-olds shared themes more actively, using explicit means, compared to 5-year-olds. The older children\u27s instructions were more informative and made in the task-appropriate referential perspective. For the purpose of establishing shared names, the older children engaged themselves in the naming process less often because they used names that can be more easily shared. The development of spatial terms for a moving referent seems to lag behind the development of those for a stationary referent. The children gradually learned, across ages and sessions, to participate to maximize the team effectiveness. Finally, dynamic changes in instructional messages were analyzed using a mode of graphic representation

Predictive cognition in dementia: the case of music

The clinical complexity and pathological diversity of neurodegenerative diseases impose immense challenges for diagnosis and the design of rational interventions. To address these challenges, there is a need to identify new paradigms and biomarkers that capture shared pathophysiological processes and can be applied across a range of diseases. One core paradigm of brain function is predictive coding: the processes by which the brain establishes predictions and uses them to minimise prediction errors represented as the difference between predictions and actual sensory inputs. The processes involved in processing unexpected events and responding appropriately are vulnerable in common dementias but difficult to characterise. In my PhD work, I have exploited key properties of music – its universality, ecological relevance and structural regularity – to model and assess predictive cognition in patients representing major syndromes of frontotemporal dementia – non-fluent variant PPA (nfvPPA), semantic-variant PPA (svPPA) and behavioural-variant FTD (bvFTD) - and Alzheimer’s disease relative to healthy older individuals. In my first experiment, I presented patients with well-known melodies containing no deviants or one of three types of deviant - acoustic (white-noise burst), syntactic (key-violating pitch change) or semantic (key-preserving pitch change). I assessed accuracy detecting melodic deviants and simultaneously-recorded pupillary responses to these deviants. I used voxel-based morphometry to define neuroanatomical substrates for the behavioural and autonomic processing of these different types of deviants, and identified a posterior temporo-parietal network for detection of basic acoustic deviants and a more anterior fronto-temporo-striatal network for detection of syntactic pitch deviants. In my second chapter, I investigated the ability of patients to track the statistical structure of the same musical stimuli, using a computational model of the information dynamics of music to calculate the information-content of deviants (unexpectedness) and entropy of melodies (uncertainty). I related these information-theoretic metrics to performance for detection of deviants and to ‘evoked’ and ‘integrative’ pupil reactivity to deviants and melodies respectively and found neuroanatomical correlates in bilateral dorsal and ventral striatum, hippocampus, superior temporal gyri, right temporal pole and left inferior frontal gyrus. Together, chapters 3 and 4 revealed new hypotheses about the way FTD and AD pathologies disrupt the integration of predictive errors with predictions: a retained ability of AD patients to detect deviants at all levels of the hierarchy with a preserved autonomic sensitivity to information-theoretic properties of musical stimuli; a generalized impairment of surprise detection and statistical tracking of musical information at both a cognitive and autonomic levels for svPPA patients underlying a diminished precision of predictions; the exact mirror profile of svPPA patients in nfvPPA patients with an abnormally high rate of false-alarms with up-regulated pupillary reactivity to deviants, interpreted as over-precise or inflexible predictions accompanied with normal cognitive and autonomic probabilistic tracking of information; an impaired behavioural and autonomic reactivity to unexpected events with a retained reactivity to environmental uncertainty in bvFTD patients. Chapters 5 and 6 assessed the status of reward prediction error processing and updating via actions in bvFTD. I created pleasant and aversive musical stimuli by manipulating chord progressions and used a classic reinforcement-learning paradigm which asked participants to choose the visual cue with the highest probability of obtaining a musical ‘reward’. bvFTD patients showed reduced sensitivity to the consequence of an action and lower learning rate in response to aversive stimuli compared to reward. These results correlated with neuroanatomical substrates in ventral and dorsal attention networks, dorsal striatum, parahippocampal gyrus and temporo-parietal junction. Deficits were governed by the level of environmental uncertainty with normal learning dynamics in a structured and binarized environment but exacerbated deficits in noisier environments. Impaired choice accuracy in noisy environments correlated with measures of ritualistic and compulsive behavioural changes and abnormally reduced learning dynamics correlated with behavioural changes related to empathy and theory-of-mind. Together, these experiments represent the most comprehensive attempt to date to define the way neurodegenerative pathologies disrupts the perceptual, behavioural and physiological encoding of unexpected events in predictive coding terms