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Finnemann, J.

Publications and source records attributed to Finnemann, J..

5 recordsLinked to original sources

Multisensory integration while learning to read: A longitudinal functional and structural MRI study

Literacy development involves the recognition and integration of auditory and visual signals and as such offers a unique opportunity to track the development of an eventually efficient multisensory processing network. To shed light on this topic we conducted a 12-month longitudinal 3 Tesla functional and structural MRI study in children beginning to receive formal literacy instruction. Twenty-three six-year-old German-speaking participants completed four fMRI sessions during which they were presented with letters, speech sounds, or their audiovisual combinations in congruent and incongruent formats. Longitudinal changes in BOLD response amplitude were assessed using linear mixed-effects models. Over the course of learning to read, we observed significant changes in modulations of BOLD activity for the congruent - incongruent contrast within a left-lateralised network encompassing the central opercular cortex, anterior supramarginal gyrus, inferior frontal gyrus (pars triangularis) and frontal pole. These effects were primarily driven by a gradual increase of response amplitude across sessions, consistent with the refinement of audiovisual integration mechanisms. Structural analyses revealed longitudinal anatomical variation within temporal, occipital, and sensorimotor regions, predominantly involving the right middle and inferior temporal gyri and bilateral temporal regions. However, changes in regional anatomy and functional activation were not significantly associated with behavioural measures of grapheme-phoneme association. Together, these findings demonstrate reorganisation within established regions known to be related to language processing and multisensory integration during early literacy development, highlighting the utility of longitudinal MRI for tracking experience-dependent neuroplastic changes in brain function and structure.

neuroscience↗

Development of Audiovisual Integration in Beginning Readers: A Longitudinal fMRI Study

Acquiring reading proficiency, unlike spoken language, requires the brain to engage several specialized neural systems to map visual symbols (letters) to their corresponding phonological sounds (audiovisual integration), laying the foundation for fluent reading. This study investigates the neural and behavioral trajectory of developing audiovisual (AV) integration during the first year of learning to read. Thirty-two healthy Hebrew-speaking first-grade children were assessed at 3 time points across the school year: beginning, middle, and end of first grade. Participants underwent behavioral testing and brain fMRI scans while performing a block-design fMRI task involving AV matching or non-matching letters and sounds. Together with improvement in behavioral test scores related to general abilities, working memory, cognitive flexibility, and phonemic abilities, a Drift Diffusion Modeling (DDM) analysis of the accuracy and reaction time across sessions suggested faster and more efficient responses as the year progressed. fMRI results showed a significant increase in activation, from the beginning to the end of the first grade, in the left superior temporal gyrus (STG), frontal cortices and parietotemporal cortices, with a shift towards left-lateralization in the fusiform gyrus at the end of the year. These findings point towards the second half of the first grade as the time window for neural specialization and lateralization to phonological and orthographic information. A significant positive correlation between the fusiform gyrus activation and naming objects and colors scores across all sessions links this neural specialization to cognitive flexibility behavioral skills. Key pointsO_LISignificant increase, predominantly between the middle and end of the first grade, in activation in fusiform, left superior temporal, frontal, and parietotemporal cortices across the first grade. C_LIO_LISignificant left lateralization in the fusiform gyrus at the end of first grade. C_LIO_LIPositive correlation between naming skills and a bilateral fusiform gyrus activation throughout the first grade. C_LI

animal behavior and cognition↗

Replay of episodic experience in human infants

Sequentially structured and temporally compressed reactivation of memory contents plays a key role for learning in the mature mammalian brain. This type of neural coding, known as replay, could also drive the enormous progress in sequential learning seen in human early life. Rodent models, however, suggest that replay emerges slowly and refines gradually in childhood. To test whether this prediction holds in humans, we introduced a novel fast event-related stimulation paradigm for infants undergoing non-invasive electroencephalography. Leveraging time-resolved decoding techniques we discovered multimodal replay already in infants as young as 10 months. Reactivation responses revealed a forward sequential structure and temporal compression of the learnt sequence by a factor of 6 to 7. These results demonstrate cued replay activity at the macroscopic level in the first year of life, an age at which it has not been found in rodent place cells. Our insights stimulate future research exploring how replay contributes to the development of fundamental human cognitive capacities including language processing and action planning.

neuroscience↗

Characterising the Photoplethysmography Pulse Waveform for Use in Human Neuroscience: The Hybrid Excess and Decay (HED) Model

Photoplethysmography (PPG) offers a widely-used, convenient and non-invasive approach to monitoring basic indices of cardiovascular function such as heart rate and blood oxygenation. However, while the pulse waveform, generated by PPG comprises features that are shaped by physiological and psychological factors, it is frequently overlooked in analyses of such data. We suggest that studies could be enriched by exploiting the possibilities afforded by a systematic analysis of PPG waveforms. To do this we initially require a robust and automated means of characterising it, thereby allowing us to examine variations across individuals and between different physiological and psychological contexts. We present a psychophysiologically-relevant model, the Hybrid Excess and Decay (HED) Model, which characterises pulse wave morphology in terms of three underlying pressure waves and a decay function. We show that these parameters capture PPG data with a high degree of precision and, moreover, are sensitive to specific, physiologically-relevant changes within individuals. We present the theoretical and practical basis for the model and demonstrate its performance when applied to a pharmacological dataset of 105 participants receiving intravenous administrations of the sympathomimetic drug isoproterenol (Isoprenaline). We conclude by discussing the possible value in using the HED model to complement standard measures of PPG outputs.

neuroscience↗

The Filter Detection Task for measurement of breathing-related interoception and metacognition

The study of the brains processing of sensory inputs from within the body ( interoception) has been gaining rapid popularity in neuroscience, where interoceptive disturbances are thought to exist across a wide range of chronic physiological and psychological conditions. Here we present a task and analysis procedure to quantify specific dimensions of breathing-related interoception, including interoceptive sensitivity (accuracy), decision bias, metacognitive bias, and metacognitive performance. Two major developments address some of the challenges presented by low trial numbers in interoceptive experiments: (i) a novel adaptive algorithm to maintain task performance at 70-75% accuracy; (ii) an extended hierarchical metacognitive model to estimate regression parameters linking metacognitive performance to relevant (e.g. clinical) variables. We demonstrate the utility of the task and analysis developments, using both simulated data and three empirical datasets. This methodology represents an important step towards accurately quantifying interoceptive dimensions from a simple experimental procedure that is compatible with clinical settings.

neuroscience↗