To reveal the relation between intellectual disability and the deleted intervals in Williams syndrome, we performed an array comparative genomic hybridization analysis and standardized developmental testing for 11 patients diagnosed as having Williams syndrome based on fluorescent in situ hybridization testing. One patient had a large 4.2-Mb deletion spanning distally beyond the common 1.
View Article and Find Full Text PDFThe present study investigated the neural correlates of infant discrimination of very similar linguistic varieties (Quebecois and Parisian French) using functional Near InfraRed Spectroscopy. In line with previous behavioral and electrophysiological data, there was no evidence that 3-month-olds discriminated the two regional accents, whereas 5-month-olds did, with the locus of discrimination in left anterior perisylvian regions. These neuroimaging results suggest that a developing language network relying crucially on left perisylvian cortices sustains infants' discrimination of similar linguistic varieties within this early period of infancy.
View Article and Find Full Text PDFEach language has a unique set of phonemic categories and phonotactic rules which determine permissible sound sequences in that language. Behavioral research demonstrates that one's native language shapes the perception of both sound categories and sound sequences in adults, and neuroimaging results further indicate that the processing of native phonemes and phonotactics involves a left-dominant perisylvian brain network. Recent work using a novel technique, functional Near InfraRed Spectroscopy (NIRS), has suggested that a left-dominant network becomes evident toward the end of the first year of life as infants process phonemic contrasts.
View Article and Find Full Text PDFUntil recently, imaging the infant brain was very challenging. Functional Near InfraRed Spectroscopy (fNIRS) is a promising, relatively novel technique, whose use is rapidly expanding. As an emergent field, it is particularly important to share methodological knowledge to ensure replicable and robust results.
View Article and Find Full Text PDFNear-infrared spectroscopy (NIRS) is a noninvasive neuroimaging tool that can measure local hemodynamic changes in the brain. Over the past decade, the technical advantage offered by multichannel NIRS has provided various new findings on higher cerebral function of the human brain. These findings have improved our knowledge of cognitive neuroscience, neurology, psychiatric medicine, rehabilitation medicine, and pharmacology.
View Article and Find Full Text PDFBackground: A growing body of evidence suggests that meditative training enhances perception and cognition. In Japan, the Park-Sasaki method of speed-reading involves organized visual training while forming both a relaxed and concentrated state of mind, as in meditation. The present study examined relationships between reading speed, sentence comprehension, and eye movements while reading short Japanese novels.
View Article and Find Full Text PDFDuring the past ten years, research using Near-infrared Spectroscopy (NIRS) to study the developing brain has provided groundbreaking evidence of brain functions in infants. This paper presents a theoretically oriented review of this wealth of evidence, summarizing recent NIRS data on language processing, without neglecting other neuroimaging or behavioral studies in infancy and adulthood. We review three competing classes of hypotheses (i.
View Article and Find Full Text PDFThis study focuses on the early cerebral base of speech perception by examining functional lateralization in neonates for processing segmental and suprasegmental features of speech. For this purpose, auditory evoked responses of full-term neonates to phonemic and prosodic contrasts were measured in their temporal area and part of the frontal and parietal areas using near-infrared spectroscopy (NIRS). Stimuli used here were phonemic contrast /itta/ and /itte/ and prosodic contrast of declarative and interrogative forms /itta/ and /itta?/.
View Article and Find Full Text PDFA number of behavioral studies suggest that infant-directed speech (IDS) plays a more important role in facilitating both: a) speech perception, and b) adult-infant social interactions than does adult-directed speech (ADS), and hence that IDS contributes to subsequent social and language development. However neural substrates that may underlie these IDS functions have not been examined. The present study examined cerebral hemodynamic responses to IDS in 48 infants (4-13 months of age) using near-infrared spectroscopy (NIRS).
View Article and Find Full Text PDFPast studies have found that, in adults, the acoustic properties of sound signals (such as fast versus slow temporal features) differentially activate the left and right hemispheres, and some have hypothesized that left-lateralization for speech processing may follow from left-lateralization to rapidly changing signals. Here, we tested whether newborns' brains show some evidence of signal-specific lateralization responses using near-infrared spectroscopy (NIRS) and auditory stimuli that elicits lateralized responses in adults, composed of segments that vary in duration and spectral diversity. We found significantly greater bilateral responses of oxygenated hemoglobin (oxy-Hb) in the temporal areas for stimuli with a minimum segment duration of 21 ms, than stimuli with a minimum segment duration of 667 ms.
View Article and Find Full Text PDFDevelopmental stuttering is a speech disorder in fluency characterized by repetitions, prolongations, and silent blocks, especially in the initial parts of utterances. Although their symptoms are motor related, people who stutter show abnormal patterns of cerebral hemispheric dominance in both anterior and posterior language areas. It is unknown whether the abnormal functional lateralization in the posterior language area starts during childhood or emerges as a consequence of many years of stuttering.
View Article and Find Full Text PDFThe present study using near-infrared spectroscopy (NIRS) examined prefrontal activation associated with maze-solving performance in adult humans. The participants were required to solve a plus-shaped maze, comparable to the one used for pigeons and human children to behaviorally assess planning processes, by moving a target square to a goal square presented on a touch-sensitive screen. The participants made incorrect responses toward a previous goal immediately after the goal jumped to the end of another arm, in parallel with but less frequently than previous participants, with shorter reaction times than when they correctly adjusted their responses.
View Article and Find Full Text PDFThis study uses near-infrared spectroscopy in young infants in order to elucidate the nature of functional cerebral processing for speech. Previous imaging studies of infants' speech perception revealed left-lateralized responses to native language. However, it is unclear if these activations were due to language per se rather than to some low-level acoustic correlate of spoken language.
View Article and Find Full Text PDFThis study examined the cerebral functional lateralization, from a phonological perspective, in children with autism spectrum disorder (ASD) and typically developing children (TDC). With near infrared spectroscopy, we measured auditory evoked-responses in the temporal areas to phonemic and prosodic contrasts in word contexts. The results of TDC showed stronger left-dominant and right-dominant responses to phonemic and prosodic differences, respectively.
View Article and Find Full Text PDFAttachment between mothers and infants is the most primitive and primary form of human social relationship. Many reports have suggested that the orbitofrontal cortex (OFC) plays a significant role in this attachment; however, only a select few provide experimental neurophysiological evidence. In the present study, to determine the neural substrates underlying the social and emotional attachment between mothers and infants, we measured their prefrontal activation by using near-infrared spectroscopy.
View Article and Find Full Text PDFNear-infrared spectroscopy (NIRS) provides a unique method of monitoring infant brain function by measuring the changes in the concentrations of oxygenated and deoxygenated hemoglobin. During the past 10 years, NIRS measurement of the developing brain has rapidly expanded. In this article, a brief discussion of the general principles of NIRS, including its technical advantages and limitations, is followed by a detailed review of the role played so far by NIRS in the study of infant perception and cognition, including language, and visual and auditory functions.
View Article and Find Full Text PDFNear-infrared spectroscopy (NIRS) enables noninvasive measurement of concentration changes of oxy- and deoxy-hemoglobin. The present study investigated cerebral representations of motion illusion by NIRS and examined several experimental procedures to determine an efficient procedure that can shorten the experimental time. We compared hemodynamic responses to figures with and without motion illusion.
View Article and Find Full Text PDFThe present study using near-infrared spectroscopy examined the neuronal correlates of Japanese long/short vowel contrast discrimination and its relationship with behavioral performance by comparing native Japanese (L1) subjects and Korean subjects learning Japanese as a second language (L2). Phoneme-specific responses were predominantly observed in the left auditory area only in the L1 subjects, although the behavioral scores of the L2 subjects indicated categorical perception (CP) that was indistinguishable from that of the L1 subjects. These inconsistent relationships were more evident in the correlation coefficients between the brain recording and behavior.
View Article and Find Full Text PDFNear-infrared spectroscopy was used to measure hemodynamic responses in Korean subjects learning Japanese as a second-language to Japanese phonemic contrasts that are either phonologically distinctive or non-distinctive in their first-language. These results were compared with those of Japanese native listeners reported previously. Unlike the results observed in the Japanese subjects, the Korean subjects did not show category-specific neural responses to a durational contrast that is non-distinctive in their first-language.
View Article and Find Full Text PDFThe present study examined cerebral representations of Japanese long and short vowel categories with near-infrared spectroscopy (NIRS) by measuring the hemodynamic changes. Results showed that NIRS could capture phoneme-specific information. The left side of the auditory area showed large hemodynamic changes only for contrasting stimuli between which the phonemic boundary was estimated, but not for stimuli differing by an equal duration but belonging to the same phoneme category.
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