On-Going Frontal Alpha Rhythms Are Dominant in Passive State and Desynchronize in Active State in Adult Gray Mouse Lemurs

PLoS One. 2015 Nov 30;10(11):e0143719. doi: 10.1371/journal.pone.0143719. eCollection 2015.

Abstract

The gray mouse lemur (Microcebus murinus) is considered a useful primate model for translational research. In the framework of IMI PharmaCog project (Grant Agreement n°115009, www.pharmacog.org), we tested the hypothesis that spectral electroencephalographic (EEG) markers of motor and locomotor activity in gray mouse lemurs reflect typical movement-related desynchronization of alpha rhythms (about 8-12 Hz) in humans. To this aim, EEG (bipolar electrodes in frontal cortex) and electromyographic (EMG; bipolar electrodes sutured in neck muscles) data were recorded in 13 male adult (about 3 years) lemurs. Artifact-free EEG segments during active state (gross movements, exploratory movements or locomotor activity) and awake passive state (no sleep) were selected on the basis of instrumental measures of animal behavior, and were used as an input for EEG power density analysis. Results showed a clear peak of EEG power density at alpha range (7-9 Hz) during passive state. During active state, there was a reduction in alpha power density (8-12 Hz) and an increase of power density at slow frequencies (1-4 Hz). Relative EMG activity was related to EEG power density at 2-4 Hz (positive correlation) and at 8-12 Hz (negative correlation). These results suggest for the first time that the primate gray mouse lemurs and humans may share basic neurophysiologic mechanisms of synchronization of frontal alpha rhythms in awake passive state and their desynchronization during motor and locomotor activity. These EEG markers may be an ideal experimental model for translational basic (motor science) and applied (pharmacological and non-pharmacological interventions) research in Neurophysiology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alpha Rhythm*
  • Animals
  • Cheirogaleidae
  • Cortical Synchronization
  • Evoked Potentials, Motor
  • Frontal Lobe / growth & development
  • Frontal Lobe / physiology*
  • Motor Activity*

Grants and funding

The activity leading to the present study has received funding from the Seventh Framework Programme of European Community (FP7/2007-2013) for the Innovative Medicine Initiative under Grant Agreement No. 115009 (www.pharmacog.org) (title of the project: “Prediction of cognitive properties of new drug candidates for neurodegenerative diseases in early clinical development”; acronym: PharmaCog). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.