Electroencephalographic and early communicative abnormalities in Brattleboro rats

Area of Science:

• Neuroscience
• Psychiatry
• Genetics

Background:

• Reduced vasopressin (VP) levels and receptors are linked to schizophrenia.
• VP is crucial for social behavior; schizophrenia presents with asociality, potentially developing early.
• Reduced auditory event-related potential (ERP) amplitudes are a schizophrenia endophenotype.

Purpose of the Study:

• To investigate the impact of VP deficiency on vocal communication during development and auditory ERPs in adulthood using Brattleboro (BRAT) rats.
• To explore the age-dependent role of VP in vocalization and auditory processing.

Main Methods:

• Utilized Brattleboro (BRAT) rats, a model of VP deficiency.
• Assessed vocalizations during early postnatal development (days 2, 5, and 9).
• Measured auditory ERPs, including N40 amplitude and gamma intertrial coherence, in adulthood.

Main Results:

• BRAT rats showed normal vocalizations on postnatal days 2 and 5 but exhibited increased vocalization intervals and reduced power from day 9 onwards.
• Adult BRAT rats displayed deficits in auditory ERPs, characterized by reduced N40 amplitude and diminished low and high gamma intertrial coherence.
• These findings indicate age-dependent effects of VP on vocal communication and impaired auditory information processing due to VP reduction.

Conclusions:

• Vasopressin plays a critical, age-dependent role in vocal communication.
• VP deficiency leads to impaired auditory information processing, evidenced by altered ERPs.
• Targeting the vasopressin system may offer a novel therapeutic strategy for negative symptoms in schizophrenia.