Sabrina Suffren

Contrary to all other sensory systems, olfactory information is processed predominantly ipsilaterally. Furthermore, odor localization, based on inter-nostril differences, is usually not possible under controlled conditions. These two observations suggest information exchange between both cerebral hemispheres in the olfactory system, although the exact anatomical substrate remains unknown. This study aimed to identify the anatomical structures necessary for odor localization, with a particular focus on the role of interhemispheric communication. We assessed the ability to localize pure olfactory and mixed olfactory/trigeminal stimuli in 6 participants with structural interhemispheric deficits (including surgical transection or agenesis of the corpus callosum (CC) and agenesis of the CC and anterior commissure (AC, one case)) and compared their performance to 46 healthy controls. Of the six participants with structural interhemispheric deficits, three were unable to localize either stimulus. Two participants performed significantly better than chance for both pure and mixed stimuli, while one participant exhibited the typical localization pattern observed in most controls—accurate localization of the mixed olfactory/trigeminal stimulus but inability to localize the pure olfactory stimulus. Our results suggest that localization of chemosensory stimuli relies, at least in part, on CC, highlighting its role in interhemispheric communication for olfactory processing. The varying odor localization performance observed in participants with agenesis of CC indicates that compensatory mechanisms may be promoted in some cases, potentially preserving normal localization functions despite the absence of major commissural pathways.

Childhood adversity and anxiety have been associated with increased risk for internalizing disorders later in life and with a range of brain structural abnormalities. However, few studies have examined the link between harsh parenting practices and brain anatomy, outside of severe maltreatment or psychopathology. Moreover, to our knowledge, there has been no research on parenting and subclinical anxiety symptoms which remain persistent over time during childhood (i.e., between 2.5 and 9 years old). Here, we examined data in 94 youth, divided into four cells based on their levels of coercive parenting (high / low) and of anxiety (high / low) between 2.5 and 9 years old. Anatomical images were analyzed using voxel-based morphometry (VBM) and FreeSurfer. Smaller gray matter volumes in the prefrontal cortex regions and in the amygdala were observed in youth with high versus low levels of harsh parenting over time. In addition, we observed significant interaction effects between parenting practices and subclinical anxiety symptoms in rostral anterior cingulate cortical thickness and in amygdala volume. These youth should be followed further in time to identify which youth will or will not go on to develop an anxiety disorder, and to understand factors associated with the development of sustained anxiety psychopathology.

Objective: To evaluate how sociodemographic characteristics and various aspects of parent well-being, family functioning, parent-child relationship, and child characteristics are related to psychological functioning in children aged 9 to 12 years during the COVID-19 lockdown. Method: Participants included 144 children aged 9 to 12 years and their parents who lived in the province of Quebec, Canada, during the COVID-19 mandatory lockdown. Parents and children were administered a phone-based survey in which various child, parent, parent-child, and family characteristics were assessed. Results: Results showed that higher internalizing problems in children were related to greater depressive symptoms in parents, lower attachment security to parents, and greater aversion to aloneness in children. Results on externalizing behavior problems showed that more problems were associated with more family dysfunction and chaos and lower attachment security to parents. Finally, results on children's anxiety toward COVID-19 showed that more anxiety was associated with greater parental anxiety toward COVID-19 and more child aversion to aloneness. Conclusion: Our findings showed that even during an unusual and stressful context such as a pandemic, proximal variables such as the attachment relationship that have been known to be closely associated with adaptation are significantly related to child psychological functioning. Such observations are important because they highlight factors that may accentuate child vulnerability in times of a pandemic and shed light on potential intervention targets.

With increasing advances in the field of medical brain imaging, the known spectrum of white matter lesions has expanded, and we can now assess the presence of punctate white matter lesions (PWML). These focal small lesions are quite frequently detected in the preterm infant and in full‐term infants with congenital heart malformations with, some studies reporting a link between these lesions and adverse long‐term outcomes. The etiology of PWML has sparked a lot of questions over the years, some of which still remain unanswered. This narrative review will bring an overview of current knowledge and their significant clinical importance in the newborn brain.