5,243 research outputs found
Standardising an infant fNIRS analysis pipeline to investigate neurodevelopment in global health
Data analysis methods for infant fNIRS data in global health are not standardised yet. This work proposes an analysis pipeline that improves the quality of the recovered HRF for use by other researchers in this field
Using fNIRS to study working memory of infants in rural Africa
A pilot study was conducted to assess the feasibility of using fNIRS as an alternative to behavioral assessments of cognitive development with infants in rural Africa. We report preliminary results of a study looking at working memory in 12â16-month-olds and discuss the benefits and shortcomings for the potential future use of fNIRS to investigate the effects of nutritional insults and interventions in global health studies
Convergent and divergent fMRI responses in children and adults to increasing language production demands
In adults, patterns of neural activation associated with perhaps the most basic language skillâovert object namingâare extensively modulated by the psycholinguistic and visual complexity of the stimuli. Do children's brains react similarly when confronted with increasing processing demands, or they solve this problem in a different way? Here we scanned 37 children aged 7â13 and 19 young adults who performed a well-normed picture-naming task with 3 levels of difficulty. While neural organization for naming was largely similar in childhood and adulthood, adults had greater activation in all naming conditions over inferior temporal gyri and superior temporal gyri/supramarginal gyri. Manipulating naming complexity affected adults and children quite differently: neural activation, especially over the dorsolateral prefrontal cortex, showed complexity-dependent increases in adults, but complexity-dependent decreases in children. These represent fundamentally different responses to the linguistic and conceptual challenges of a simple naming task that makes no demands on literacy or metalinguistics. We discuss how these neural differences might result from different cognitive strategies used by adults and children during lexical retrieval/production as well as developmental changes in brain structure and functional connectivity
Infant cortex responds to other humans from shortly after birth
A significant feature of the adult human brain is its ability to selectively process information about conspecifics. Much debate has centred on whether this specialization is primarily a result of phylogenetic adaptation, or whether the brain acquires expertise in processing social stimuli as a result of its being born into an intensely social environment. Here we study the haemodynamic response in cortical areas of newborns (1â5 days old) while they passively viewed dynamic human or mechanical action videos. We observed activation selective to a dynamic face stimulus over bilateral posterior temporal cortex, but no activation in response to a moving human arm. This selective activation to the social stimulus correlated with age in hours over the first few days post partum. Thus, even very limited experience of face-to-face interaction with other humans may be sufficient to elicit social stimulus activation of relevant cortical regions
Diminished socially selective neural processing in 5-month-old infants at high familial risk of autism
The social and communicative difficulties that characterize autism spectrum disorder (ASD) are considered the most striking fea-ture of the disorder. Research has reported that individuals with ASD show abnormalities in the brain regions associated with theprocessing of social information. Importantly, a recent study using functional near-infrared spectroscopy (fNIRS) found the firstevidence of atypicalities in the neural processing of social information in 4- to 6-month-old infants at high familial risk of ASD.These findings provide an important step in the search for early markers of ASD and highlight the potential for neuroimaging tech-niques to detect atypical patterns of neural activity prior to the manifestation of most behavioural symptoms. This study aimed toextend the findings of reduced neural sensitivity to social stimuli in an independent cohort. Twenty-nine 5-month-old infants (13low-risk infants, 16 high-risk infants) were presented with social and non-social visual stimuli, similar to the previous experiment.Importantly, a non-social dynamic motion control condition was introduced allowing the comparison between social dynamic andnon-social, static, as well as dynamic stimuli. We found that while low-risk infants showed activation to social stimuli in the rightposterior temporal cortex, this activation was reduced in infants at high risk of ASD. Although the current sample size was rela-tively small, our results replicate and extend previous work and provide evidence for a social processing difference in infants atrisk of autism. Future research will determine whether these differences relate to an eventual ASD diagnosis or may rather reflectthe broader autism phenotype
Reduced neural sensitivity to social stimuli in infants at risk for autism
In the hope of discovering early markers of autism, attention has recently turned to the study of infants at risk owing to being the younger siblings of children with autism. Because the condition is highly heritable, later-born siblings of diagnosed children are at substantially higher risk for developing autism or the broader autism phenotype than the general population. Currently, there are no strong predictors of autism in early infancy and diagnosis is not reliable until around 3 years of age. Because indicators of brain functioning may be sensitive predictors, and atypical social interactions are characteristic of the syndrome, we examined whether temporal lobe specialization for processing visual and auditory social stimuli during infancy differs in infants at risk. In a functional near-infrared spectroscopy study, infants aged 4â6 months at risk for autism showed less selective neural responses to social stimuli (auditory and visual) than low-risk controls. These group differences could not be attributed to overall levels of attention, developmental stage or chronological age. Our results provide the first demonstration of specific differences in localizable brain function within the first 6 months of life in a group of infants at risk for autism. Further, these differences closely resemble known patterns of neural atypicality in children and adults with autism. Future work will determine whether these differences in infant neural responses to social stimuli predict either later autism or the broader autism phenotype frequently seen in unaffected family members
Biology, Ecology and Range of the Bobcat, Lynx Rufus in New York and its Inferred Interactions with Potentially Reintroduced Lynx, Lynx canadensis canadensis in Adirondack Park
1. To determine and describe the predation ecology, movement patterns, territorial behavior and habitat of bobcats in New York. 2. To determine vital population characteristics and exploitation levels of bobcats in New York. 3. To recommend management alternatives for bobcats in New York on the basis of an information synthesis, range map and model of current bobcat exploitation levels in the region. 4. To make recommendations concerning the feasibility of lynx reintroduction in Adirondack Park based on the inferred level of lynx-bobcat competition and a survey of potential lynx range in the Park
Functional near infrared spectroscopy (fNIRS) to assess cognitive function in infants in rural Africa
Cortical mapping of cognitive function during infancy is poorly understood in low-income countries due to the lack of transportable neuroimaging methods. We have successfully piloted functional near infrared spectroscopy (fNIRS) as a neuroimaging tool in rural Gambia. Four-to-eight month old infants watched videos of Gambian adults perform social movements, while haemodynamic responses were recorded using fNIRS. We found distinct regions of the posterior superior temporal and inferior frontal cortex that evidenced either visual-social activation or vocally selective activation (vocal > non-vocal). The patterns of selective cortical activation in Gambian infants replicated those observed within similar aged infants in the UK. These are the first reported data on the measurement of localized functional brain activity in young infants in Africa and demonstrate the potential that fNIRS offers for field-based neuroimaging research of cognitive function in resource-poor rural communities
Functional near infrared spectroscopy (fNIRS) to assess cognitive function in infants in rural Africa
Cortical mapping of cognitive function during infancy is poorly understood in low-income countries due to the lack of transportable neuroimaging methods. We have successfully piloted functional near infrared spectroscopy (fNIRS) as a neuroimaging tool in rural Gambia. Four-to-eight month old infants watched videos of Gambian adults perform social movements, while haemodynamic responses were recorded using fNIRS. We found distinct regions of the posterior superior temporal and inferior frontal cortex that evidenced either visual-social activation or vocally selective activation (vocal > non-vocal). The patterns of selective cortical activation in Gambian infants replicated those observed within similar aged infants in the UK. These are the first reported data on the measurement of localized functional brain activity in young infants in Africa and demonstrate the potential that fNIRS offers for field-based neuroimaging research of cognitive function in resource-poor rural communities
Brain responses reveal young infantsâ sensitivity to when a social partner follows their gaze
Infantsâ ability to follow another person's eye gaze has been studied extensively and is considered to be an important and early emerging social cognitive skill. However, it is not known whether young infants detect when a social partner follows their gaze to an object. This sensitivity might help infants in soliciting information from others and serve as an important basis for social learning. In this study, we used functional near-infrared spectroscopy (fNIRS) to measure 5-month-old infantsâ frontal and temporal cortex responses during social interactions in which a social partner (virtual agent) either followed the infantsâ gaze to an object (congruent condition) or looked to an object that the infant had not looked at before (incongruent condition). The fNIRS data revealed that a region in the left prefrontal cortex showed an increased response when compared to baseline during the congruent condition but not during the incongruent condition, suggesting that infants are sensitive to when someone follows their gaze. The findings and their implications for the development of early social cognition are discussed in relation to what is known about the brain processes engaged by adults during these kinds of social interactions
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