Altered patterning of neural activity in a tauopathy mouse model

Area of Science:

• Neuroscience
• Computational Neuroscience
• Neurodegenerative Diseases

Background:

• Alzheimer's disease (AD) involves complex neurodegenerative changes from cellular to cognitive levels.
• Tau-pathology is a key hallmark of AD, significantly impacting brain function.
• Conventional analyses of neuronal activity often overlook intermediate timescales.

Purpose of the Study:

• To investigate the impact of AD-related tau-pathology on hippocampal circuits during spatial navigation.
• To analyze changes in neuronal firing and extracellular field dynamics at intermediate timescales.
• To identify novel neurodynamic markers of hippocampal circuit disruption in AD.

Main Methods:

• Utilized tau-pathology mouse models (tau-mice) for spatial navigation tasks.
• Focused analysis on spike trains and oscillatory potential waveforms at intermediate timescales.
• Correlated neural activity patterns with animal's locomotion (location, speed, acceleration).

Main Results:

• Healthy mice exhibit coupled spike arrangements and wave patterns with locomotion.
• Tau-mice display structurally disarrayed neural activity, detached from locomotion.
• Loss of spatial selectivity and scrambled spike flow were observed in tau-mice.
• Alterations in neural activity initiate early and worsen with age in tau-mice.

Conclusions:

• Tau-pathology leads to significant disruptions in hippocampal circuit dynamics during spatial navigation.
• Intermediate timescale analyses reveal salient neurodynamic changes missed by conventional methods.
• Progressive disinvolvement of the hippocampus in spatial navigation is evident in tau-pathology.
• These findings offer a new perspective on hippocampal circuit disruptions in Alzheimer's disease.