ALTERED RESPONSIVENESS DURING HYPERVENTILATION-INDUCED EEG SLOWING - A NONEPILEPTIC PHENOMENON IN NORMAL-CHILDREN

The relation between hyperventilation (HV)-induced high-amplitude rhyt hmical slowing (HIHARS) and altered responsiveness without generalized spike and wave activity has not been clearly defined. To test whether altered responsiveness is a nonspecific physiologic response rather t han a symptom of generalized epilepsy, we assessed verbal recall abili ty and motor response testing in 12 healthy nonepileptic children (mea n age 9.6 years). Both tasks were administered as a baseline before HV , during HV but before onset of EEG slowing, and during HIHARS. Verbal recall and motor responsiveness remained unchanged during baseline an d HV before onset of slowing. During HIHARS, all children exhibited im paired verbal recall (p < 0.005) and 8 of 12 failed to respond to repe ated auditory clicks (p < 0.005). Our findings indicate that in a norm al setting, responsiveness may be impaired during HV in healthy nonepi leptic children.