High resolution, wide field optical imaging of macaque visual cortex with a curved detector

Abstract

Objective. Cortical activity can be recorded using a variety of tools, ranging in scale from the single neuron (microscopic) to the whole brain (macroscopic). There is usually a trade-off between scale and resolution; optical imaging techniques, with their high spatio-temporal resolution and wide field of view, are best suited to study brain activity at the mesoscale. Optical imaging of cortical areas is however in practice limited by the curvature of the brain, which causes the image quality to deteriorate significantly away from the center of the image. Approach. To address this issue and harness the full potential of optical cortical imaging techniques, we developed a new wide-field optical imaging system adapted to the macaque brain. Our system is composed of a curved detector, an aspherical lens and a ring composed of LEDs providing uniform illumination at wavelengths relevant for the different optical imaging methods, including intrinsic and fluorescence imaging. Main Results. The system was characterized and compared with the standard macroscope used for cortical imaging, and a 3-fold increase of the area in focus was measured as well as a 4-fold increase in the evenness of the optical quality in vivo. Significance. This new instrument, which is to the best of our knowledge the first use of a curved detector for cortical imaging, should facilitate the observation of wide mesoscale phenomena such as dynamic propagating waves within and between cortical maps, which are otherwise difficult to observe due to technical limitations of the currently available recording tools.

Fast and wide field off-axis three-mirror optical system design with curved detector for planetary exploration

“…Recent advances in curved detector technology have achieved comparable optoelectronic performance to that of commercial flat detectors [9]. At the same time, curved detectors can compensate for the field curvature aberration of the optical system directly at the image plane position, thus reducing the pressure on the optical system to correct for aberrations [10][11]. Therefore, the application of curved detectors is expected to further break the volume boundary of freeform optical systems.…”

Image2Brain: a cross-modality model for blind stereoscopic image quality ranking

“…However, visual perception is a complex process, previous NR-SIQA methods by extracting image features are more related to the employed training set rather than general principles [13], which may not meet human cognitive criteria well. According to biological theory, human beings perceive visual information from the scenario through the visual cortex of the brain [14][15][16]. Thus, if we can replicate the cerebral perception on stereoscopic image quality to a machine, the quality of stereoscopic images would be evaluated more accurately.…”