Maternal deprivation induces alterations in cognitive and cortical function in adulthood

Area of Science:

• Neuroscience
• Neurobiology
• Psychiatry

Background:

• Early life trauma is a significant risk factor for neuropsychiatric disorders, including schizophrenia.
• Maternal deprivation (MD) is a specific early life stressor with known long-term effects.

Purpose of the Study:

• To investigate how maternal deprivation (MD) in rodents affects cognitive function and brain activity in adulthood.
• To examine the expression of key neurotransmitter-related enzymes and bioelectric activity following early life trauma.

Main Methods:

• Rats underwent maternal deprivation during the early postnatal period.
• Adult rats were assessed for recognition memory using the novel object recognition task.
• Quantification of catechol-o-methyl transferase (COMT) and glutamic acid decarboxylase (GAD67) expression in specific brain regions (mPFC, ventral striatum, TC).
• Depth EEG recordings were performed to evaluate sensory gating and bioelectric noise.

Main Results:

• Maternally deprived (MD) animals showed impaired recognition memory.
• Reduced expression of COMT in the medial prefrontal cortex (mPFC) and temporal cortex (TC), and GAD67 in the TC was observed in MD animals.
• MD led to increased bioelectric noise and altered information processing in sensory gating tasks.
• Information-theoretic measures revealed altered shared information between cognitive and sensory processing areas.

Conclusions:

• Neurodevelopmental perturbations from early life trauma cause persistent cognitive and brain function alterations.
• Findings link early life stress to changes in COMT and GAD67 expression and bioelectric noise, consistent with human studies.
• Altered information flow between brain regions following MD provides a potential mechanism for increased risk of neurodevelopmental disorders like schizophrenia.