Ventral and Intermediate Hippocampus Are Required for Object-in-Place Recognition Memory in Mice

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Cognitive Neuroscience

Background:

• Identity-location associations are vital for survival behaviors like foraging and predator avoidance.
• Object-in-place (OiP) recognition memory tasks assess these associations, with deficits linked to autism, schizophrenia, and Alzheimer's disease.
• Neural underpinnings of OiP memory in mice, a key model organism, remain largely unknown.

Purpose of the Study:

• To investigate the contribution of specific brain regions to OiP recognition memory in mice.
• To elucidate the role of ventral and intermediate CA1 hippocampal subregions (vCA1, iCA1) and medial prefrontal cortex (mPFC) in OiP memory.

Main Methods:

• Chemogenetics was employed to manipulate neuronal activity in vCA1, iCA1, and mPFC.
• The study assessed OiP recognition memory performance in male and female C57BL/6J mice.
• Contribution of iCA1-mPFC projections was also evaluated.

Main Results:

• Activity in both the vCA1 and iCA1 hippocampal subregions is essential for successful two-object OiP recognition memory.
• The mPFC and iCA1-mPFC connections were not found to be critical for OiP memory performance.
• This research identifies specific hippocampal subregions required for OiP memory assessment in mice.

Conclusions:

• The ventral and intermediate CA1 hippocampal subregions play a critical role in object-in-place recognition memory in mice.
• These findings expand the understanding of the neural basis of spatial memory processing.
• This study provides novel insights into the neural substrates of OiP memory, relevant for modeling human neurological disorders.