It’s all about BOLD

BOLD fMRI, firstly described by Ogawa and his colleagues, is a non-invasive imaging technique that measures changes in its local magnetic field properties caused by the amount of deoxygenated hemoglobin in the activated brain tissue. Although it has been overwhelmingly applied to generate functional images in the human brain, it indeed reflects the competing effects of blood flow, blood volume and oxygen/glucose consumption, caused by variations in neuronal activity. We have begun to record neural and hemodynamic responses in the primary visual cortex while the primates were trained to consciously view a visual pattern presented on a computer screen. Through an implanted ‘window’ on the brain (as shown below), both local field potential (LFP) and multi-unit activity (MUA) were simultaneously recorded by a microelectrode.
 

Dimensions: 10.78*8.68mm (539*434 pixels, each pixel 20um)

Not to be reproduced without concent of authors Zheng Wang, Ravi Menon.