Response properties of local field potentials and multiunit activity in the mouse visual cortex
1Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Experimental Otology, Institute of Audioneurotechnology, Hannover Medical School, 30625 Hannover, Germany.
Neuroscience
|September 17, 2013
Summary
This study examined population neural signals, including local field potentials (LFPs) and multiunit activity (MUA), in mouse visual cortex. Results show broad tuning but absent orientation and direction preferences, limiting their use for characterizing specific visual stimuli.
Area of Science:
- Neuroscience
- Visual Neuroscience
- Computational Neuroscience
Background:
- Extracellular local field potentials (LFPs) and multiunit activity (MUA) represent integrated neural activity in cortical structures.
- These population signals show stimulus feature selectivity in cat and primate visual cortices.
- The visual stimulus selectivity of population signals in the mouse visual cortex remains underexplored.
Purpose of the Study:
- To characterize the visual stimulus selectivity of LFPs and MUA in the mouse visual cortex.
- To determine the usability and limitations of these population signals for characterizing visual stimulus properties.
Main Methods:
- Recorded LFPs and MUA using multielectrode arrays in isoflurane-anesthetized C57Bl/6 mice.
- Analyzed onset latency, receptive field properties, and preferences for direction, orientation, spatial, and temporal frequencies.
- Utilized derived measures: high-pass filtered continuous MUA and bipolar spatial derivative of LFP.
Main Results:
- Population signals exhibited short onset latencies (∼30ms) and large receptive fields (up to ∼38°).
- MUA receptive fields were smaller than LFP receptive fields.
- All signals showed similar spatial (∼0.1 cycles/degree) and temporal (∼1 cycle/second) frequency preferences, but broad tuning.
- Orientation and direction of motion preferences were absent in all population signals.
Conclusions:
- Mouse visual cortex population signals (LFPs and MUA) have distinct receptive field sizes and short onset latencies.
- Broad spatial and temporal frequency tuning, coupled with absent orientation/direction preferences, limits their application in detailed stimulus characterization.
- Further research is needed to understand the full utility and limitations of these signals in visual neuroscience.
Keywords:
ANOVACRTDIHSDLFPMUAOISDSEanalysis of variancecMUAcathode ray tubecontinuous multiunit activitycpdcpscycles per degreecycles per seconddLFPderivative of the LFPdirection indexhonestly significant differencelocal field potentialmousemultiunit activityorientation indexreceptive fieldsstandard deviationstandard errorstimulus selectivityvisual cortex