One right can make a left: sentence processing in the right hemisphere after perinatal stroke

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Cognitive Neuroscience

Background:

• Perinatal strokes can damage critical brain regions for adult cognitive functions.
• Understanding brain plasticity is crucial for predicting functional outcomes after early brain injury.

Purpose of the Study:

• To investigate language organization in the right hemisphere (RH) following perinatal strokes affecting the left hemisphere (LH).
• To determine if RH language recruitment in individuals with left hemisphere perinatal stroke (LHPS) mirrors typical LH organization.

Main Methods:

• fMRI data analyzed from 14 LHPS participants and 11 healthy controls during an auditory sentence comprehension task.
• A "top voxel" approach was used to standardize the comparison of active brain voxels across hemispheres and participants.
• Functional brain organization was compared between hemispheres in LHPS participants and controls.

Main Results:

• LHPS participants consistently recruited RH areas that mirrored typical LH language regions.
• The RH areas activated in LHPS participants showed better alignment with typical LH areas than with typical RH areas.
• Recruitment patterns in the RH were more similar to the strongly activated LH areas of controls.

Conclusions:

• Successful language development in the RH after an LH perinatal stroke may involve recruiting a specific arrangement of frontotemporal areas.
• This RH arrangement appears to reflect the typical dominant LH language network organization.
• Findings suggest a conserved pattern of neural organization for language despite early-onset brain injury.