Maternal deprivation induces deficits in temporal memory and cognitive flexibility and exaggerates synaptic...

Area of Science:

• Neuroscience
• Developmental Psychology
• Behavioral Neuroscience

Background:

• Early life adverse events, such as maternal deprivation (MD), can negatively impact brain development.
• The prefrontal cortex (PFC) is particularly vulnerable to early life stress and is crucial for executive functions.

Purpose of the Study:

• To investigate the long-term effects of MD on PFC-dependent executive functions, neuronal and astrocyte populations, and synaptic plasticity in adult male rats.
• To determine if observed cognitive deficits correlate with structural or functional changes in the medial PFC (mPFC).

Main Methods:

• Male Long-Evans rats underwent daily maternal deprivation from postnatal day 1-14.
• Cognitive functions were assessed in adulthood using the temporal order memory task (TMT), attentional set-shifting task (ASST), and Morris water maze task (WMT).
• Neuronal and astrocyte counts in the prelimbic area of the mPFC were quantified using stereology, and in vivo field potentials were recorded to assess long-term potentiation (LTP) in the PrL area.

Main Results:

• MD induced cognitive deficits in PFC-dependent TMT and ASST, but not in the non-PFC-dependent WMT.
• Maternal deprivation resulted in an upregulation of LTP in the prelimbic area of the mPFC.
• No significant changes were observed in the number of neurons or astrocytes in the mPFC following MD.

Conclusions:

• Maternal deprivation in early life leads to lasting impairments in PFC-dependent executive functions in adult male rats.
• Exaggerated synaptic plasticity (LTP) in the mPFC, without changes in cell numbers, may underlie these cognitive deficits.
• These findings highlight the critical role of early life experiences in shaping PFC function and cognitive abilities throughout life.