Intrinsic Infant Hippocampal Function Supports Inhibitory Processing

Area of Science:

• Neuroscience
• Developmental Psychology
• Brain Imaging

Background:

• Impaired cerebral inhibition is a hallmark of neurodevelopmental disorders.
• The hippocampus is vital for adult inhibitory functions and undergoes rapid development in infancy.
• Hippocampal function in early development is a potential indicator for inhibitory dysfunction.

Purpose of the Study:

• To investigate the relationship between hippocampal activity and sensory gating in early infancy.
• To determine if hippocampal function in the early postnatal period correlates with inhibitory processing.
• To explore the hippocampus as a candidate region for early identification of neurodevelopmental pathologies.

Main Methods:

• Resting-state functional magnetic resonance imaging (fMRI) measured hippocampal activity (ALFFs, fractional ALFF) in 18 infants (4-20 weeks old).
• Electroencephalography (EEG) assessed sensory gating using a paired-stimulus paradigm (P50 ratio).
• Correlational analysis examined the link between right hippocampal activity and sensory gating performance.

Main Results:

• Higher activity in the right hippocampus was significantly associated with better sensory gating (lower P50 ratio).
• This association was driven by a reduced response to the second stimulus in the paired-stimulus paradigm.
• Findings indicate detectable hippocampal contributions to inhibitory processing in early infancy.

Conclusions:

• Intrinsic hippocampal activity in the early postnatal period may support effective inhibitory processing.
• The right hippocampus is a potential early biomarker for inhibitory dysfunction relevant to neurodevelopmental disorders.
• Longitudinal studies are needed to track hippocampal function trajectory and its role in neurodevelopmental disorder risk and intervention.