Biological Cybernetics

, Volume 106, Issue 3, pp 169–176 | Cite as

A computational model for the modulation of the prepulse inhibition of the acoustic startle reflex

  • David Fernando Ramirez-MorenoEmail author
  • Terrence Joseph Sejnowski
Original Paper


The acoustic startle reflex (ASR), a defensive response, is a contraction of the skeletal and facial muscles in response to an abrupt, intense (> 80 db) auditory stimulus, which has been extensively studied in rats and humans. Prepulse inhibition (PPI) of ASR is the normal suppression of the startle reflex when an intense stimulus is preceded by a weak non-starting pre-stimulus. PPI, a measure of sensory motor gating, is impaired in various neuropsychiatric disorders, including schizophrenia, and is modulated by cognitive and emotional contexts such as fear and attention. We have modeled the fear modulation of PPI of ASR based on its anatomical substrates and taking into account data from behaving rats and humans. The model replicates the principal features of both phenomena and predicts underlying neural mechanisms. In addition, the model yields testable predictions.


Acoustic startle reflex Prepulse inhibition Fear modulation PPI computational model 



Acoustic startle reflex


Prepulse inhibition




Cochlear root nucleus


Nucleus reticularis pontine caudalis


Motor neuron


Inferior colliculus


Superior colliculus


Pontine tegmental nucleus




Modulatory structure


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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • David Fernando Ramirez-Moreno
    • 1
    Email author
  • Terrence Joseph Sejnowski
    • 2
    • 3
  1. 1.Departamento de FísicaUniversidad Autonoma de OccidenteCaliColombia
  2. 2.Computational Neurobiology Laboratory, Howard Hughes Medical Institute, Salk InstituteLa JollaUSA
  3. 3.Division of Biological SciencesUniversity of California San DiegoLa JollaUSA

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