- 著者
-
Sawahata Hirohito
Toda Haruo
Suzuki Takafumi
Hasegawa Isao
- 出版者
- Niigata University School of Medicine
- 雑誌
- Acta medica et biologica = Acta medica et biologica (ISSN:05677734)
- 巻号頁・発行日
- vol.58, no.2, 2011-09
The primary visual cortex (V1) of the rat consists of a monocular (contralateral-eye-dominant) region (V1M) and a binocular region (V1B) that receives anatomical and functional inputs converging from both eyes. However, V1B contains a heterogeneous mosaic of neurons stochastically discharging with various degrees of ocular dominance, and it has been difficult to 5 estimate the size and behavior of the neuronal populations recruited by stimulation to individual eyes. To functionally characterize the V1B, we explore the similarities and differences of activation patterns between the contralateral and ipsilateral visual stimulation conditions in V1. Using a high density electrode array, 32-channel electrocorticogram (ECoG) was recorded from the whole surface of V1 of anesthetized Long-Evans rats. Despite a similarity of the spatial 10 activation patterns in the early phase, contralateral eye stimulation evoked consistently stronger responses and higher signal coherency between the most responsive site and adjacent sites than ipsilateral stimulation. Time-frequency analyses confirmed that contralateral activations were more widely distributed from V1B to V1M in low frequency powers (2-30 Hz). On the other hand, high frequency powers (30-100 Hz) were localized in V1B. These findings revealed 15 time-frequency domain properties of V1B. We speculate that the sustained high frequency activity reflected visual information flow from V1B to higher cortical centers.