Related Experiment Video
Updated: Aug 9, 2026
Assessment of Memory Function in Pilocarpine-induced Epileptic Mice
Published on: June 4, 2020
Pilocarpine seizures cause age-dependent impairment in auditory location discrimination
John C Neill1, Zhao Liu, Mohammad Mikati
1Children's Hospital, Boston, USA. John.Neill@Liu.edu
Insights
Status epilepticus, or continuous seizures, can impair auditory discrimination in young rats. This impairment is age-dependent and may affect auditory processing in humans.
Area of Science:
- Neuroscience
- Developmental Neuroscience
- Auditory Neuroscience
Background:
- Status epilepticus (SE) involves continuous or rapidly recurring seizures, posing life-threatening risks and potential for lifelong neurological and behavioral changes.
- The impact of SE on auditory discrimination abilities remains largely unexplored.
- Understanding SE's effects on sensory processing is crucial for addressing developmental neurological disorders.
Purpose of the Study:
- To investigate the long-term effects of status epilepticus on auditory discrimination in an animal model.
- To determine if the age at which SE occurs influences the severity of auditory deficits.
Main Methods:
- A naturalistic auditory location discrimination task was employed using male Sprague-Dawley rats.
- Rats were induced with status epilepticus via pilocarpine injection on postnatal day 20 (P20) or P45, or received saline as a control.
- Auditory discrimination learning (sound-source location and sound-silence) was assessed in mature rats.
Main Results:
- Rats that experienced SE on P20 showed moderate impairment in acquiring sound-source location discrimination.
- Rats that experienced SE on P45 exhibited significant deficits, failing to learn either sound-source location or sound-silence discriminations.
- SE induced CA3 cell loss and spontaneous seizures in P45 rats, but not in P20 rats.
Conclusions:
- Status epilepticus causes age-dependent, long-term impairments in auditory discrimination in rats.
- Early-life SE may lead to more severe and persistent auditory processing deficits compared to later-life SE.
- These findings suggest a potential mechanism for impaired auditory location discrimination observed in human survivors of SE.
Abstract:
Children who have status epilepticus have continuous or rapidly repeating seizures that may be life-threatening and may cause life-long changes in brain and behavior. The extent to which status epilepticus causes deficits in auditory discrimination is unknown. A naturalistic auditory location discrimination method was used to evaluate this question using an animal model of status epilepticus. Male Sprague-Dawley rats were injected with saline on postnatal day (P) 20, or a convulsant dose of pilocarpine on P20 or P45. Pilocarpine on either day induced status epilepticus; status epilepticus at P45 resulted in CA3 cell loss and spontaneous seizures, whereas P20 rats had no cell loss or spontaneous seizures. Mature rats were trained with sound-source location and sound-silence discriminations. Control (saline P20) rats acquired both discriminations immediately. In status epilepticus (P20) rats, acquisition of the sound-source location discrimination was moderately impaired. Status epilepticus (P45) rats failed to acquire either sound-source location or sound-silence discriminations. Status epilepticus in rat causes an age-dependent, long-term impairment in auditory discrimination. This impairment may explain one cause of impaired auditory location discrimination in humans.
