Somatosensory lateralization in the newborn brain.

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Human Brain Development

Background:

• Hemispheric lateralization is a key feature of the mature human brain.
• The precise timing of the onset and early development of brain lateralization remains largely unknown.
• Understanding early lateralization is crucial for comprehending typical and atypical brain development.

Purpose of the Study:

• To investigate the early postnatal development of hemispheric lateralization in the human brain.
• To examine cortical activation patterns in neonates in response to somatosensory stimuli.
• To determine if hemispheric lateralization is present in the somatosensory system at term.

Main Methods:

• Utilized functional magnetic resonance imaging (fMRI) to measure brain activity in neonates.
• Studied cortical activation induced by passive extension and flexion of the left and right hands.
• Analyzed somatosensory areas in the pre- and postcentral gyri for hemispheric lateralization.

Main Results:

• No significant hemispheric lateralization was observed in the somatosensory areas of neonates at term.
• Independent left- and right-hand stimulation experiments showed distinct patterns.
• A trend towards contralateral lateralization of the somatosensory system was suggested around the term period.

Conclusions:

• The human brain's somatosensory system does not exhibit significant hemispheric lateralization at birth.
• Emerging contralateral lateralization in the somatosensory system begins around the term gestational age.
• This study provides insights into the early developmental trajectory of brain lateralization.