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Updated: May 17, 2026
08:45
Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example
Published on: October 24, 2012
In search of noise-induced bimodality.
Kyung Hyuk Kim1, Herbert M Sauro
1Department of Bioengineering, University of Washington, William H Foege Building, Box 355061, Seattle, WA 98195-5061, USA. kkim@uw.edu
BMC Biology
|November 9, 2012
Summary
Biological noise causes cell-to-cell variability, impacting system responses. A study shows this noise can induce bimodal distributions in cellular signaling pathways, leading to unexpected biological outcomes.
Area of Science:
- Systems Biology
- Cellular Biology
- Biophysics
Background:
- Biological studies often use large cell populations for sufficient measurement material.
- Cell-to-cell variability, or biological noise, is inherent in seemingly identical cell populations.
- This variability can significantly influence system responses to environmental stimuli.
Discussion:
- Noise can lead to dramatic and counter-intuitive biological outcomes.
- A recent study highlights noise-induced bimodality in cellular responses.
- This phenomenon affects signaling pathways like the extracellular signal-regulated kinase (ERK) pathway.
Key Insights:
- Biological noise is a critical factor in cellular behavior, not just a measurement artifact.
- Noise can induce distinct subpopulations within a seemingly homogeneous cell population.
- The observed bimodality in ERK activation by epidermal growth factor was solely noise-induced.
Outlook:
- Further research into noise-induced phenomena can reveal novel biological mechanisms.
- Understanding noise is crucial for accurate interpretation of high-throughput biological data.
- This highlights the need to incorporate stochastic modeling in systems biology.
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