The fiber-optic imaging and manipulation of neural activity during animal behavior

• Published in: Neuroscience research 2016-02, Vol.103, p.1-9
• Main Authors: Miyamoto, Daisuke, Murayama, Masanori
• Format: Article
• Language: English
• Subjects: Animals; Behavior, Animal - physiology; Brain - anatomy & histology; Brain - physiology; Ca2+ imaging; Electrophysiology; Fiber Optic Technology - instrumentation; Fiber Optic Technology - methods; Freely moving animals; Graded index lenses; Neuroimaging - instrumentation; Neuroimaging - methods; Neurons - physiology; Optical fibers; Optogenetics
• ISSN: 0168-0102; 1872-8111
• DOI: 10.1016/j.neures.2015.09.004

•Fiber-optic methods allow us to image or manipulate neural activity in vivo.•Combination with other techniques enhanced the availability.•The methods are useful for dissecting complex neural circuits. Recent progress with optogenetic probes for imaging and manipulating neural activity has further increased the relevance of fiber-optic systems for neural circuitry research. Optical fibers, which bi-directionally transmit light between separate sites (even at a distance of several meters), can be used for either optical imaging or manipulating neural activity relevant to behavioral circuitry mechanisms. The method's flexibility and the specifications of the light structure are well suited for following the behavior of freely moving animals. Furthermore, thin optical fibers allow researchers to monitor neural activity from not only the cortical surface but also deep brain regions, including the hippocampus and amygdala. Such regions are difficult to target with two-photon microscopes. Optogenetic manipulation of neural activity with an optical fiber has the advantage of being selective for both cell-types and projections as compared to conventional electrophysiological brain tissue stimulation. It is difficult to extract any data regarding changes in neural activity solely from a fiber-optic manipulation device; however, the readout of data is made possible by combining manipulation with electrophysiological recording, or the simultaneous application of optical imaging and manipulation using a bundle-fiber. The present review introduces recent progress in fiber-optic imaging and manipulation methods, while also discussing fiber-optic system designs that are suitable for a given experimental protocol.