Advantages and limitations of brain imaging methods in the research of absence epilepsy in humans and animal models.

The purpose of this review is to analyze research possibilities and limitations of several methods, technical tools and their combinations for elucidation of absence epilepsy mechanisms, particularly the childhood absences. Despite the notable collection of simultaneous recording of clinical electroencephalography (EEG) and behavioral changes in relation to absence seizures, shortcomings of scalp EEG in both spatial resolution and precise detection of subcortical centers have limited the understanding of the fundamental mechanisms of altered brain function during and after recurrent epileptic paroxysms. Therefore, in the past decade, EEG recordings have often been combined with simultaneous imaging methods in epilepsy studies.

Use of a simplified method of optical recording to identify foci of maximal neuron activity in the somatosensory cortex of white rats.

Eight mongrel white male rats were studied under urethane anesthesia, and neuron activity evoked by mechanical and/or electrical stimulation of the contralateral whiskers was recorded in the primary somatosensory cortex. Recordings were made using a digital USB chamber attached to the printer port of a Pentium 200MMX computer running standard programs. Optical images were obtained in the barrel-field zone using a differential signal, i.

[Application of the simplified method of optic recording for mapping focuses of the neuronal activity in the somatosensory cortex of the white rats].

In rats, a differential signal was used for evoking an optical image in the barrel-field zone which represented a difference between cortical images during the control and the stimulation periods. After a subtraction of averaged sequences of frames, an image of spots reflecting a probable location of activated groups of neurones was obtained. Natural low frequency stimulation of vibrissae is supposed to be the most effective.