##  [Heart Rate Variability](/heart-rate-variability) 

  ##  [Heart Rate Variability](https://health.quantumdictionary.io/heart-rate-variability-0) 

  

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**Health & Life Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The variation in successive inter-beat intervals (commonly NN or RR intervals) quantified by time-domain, frequency-domain or non-linear metrics from electrocardiographic or beat-to-beat recordings, used as an indirect indicator of autonomic nervous system modulation and physiological state in animals; interpretation depends on species, recording protocol and signal preprocessing.