In this episode, we discussed methods to measure brain activity and the important trade-off between spatial (where) and temporal (when) resolution. We also explored the relative significance of understanding brain activity in space vs. time, and finally went on to talk about some novel methods that are breaking this barrier and achieving both high spatial and temporal resolution.
While imaging methods can be used to visualise brain activity across space, they give little information about the temporal dynamics of activity; whereas electrophysiology methods are used to measure electrical activity with high temporal precision, but are usually restricted in what they can tell us about where the activity is occuring.
Here is a great figure summarising the major techniques used in neuroscience research and their spatio-temporal resolution:

Grinvald, A., Hildesheim, R. VSDI: a new era in functional imaging of cortical dynamics. Nat Rev Neurosci5, 874–885 (2004). https://doi.org/10.1038/nrn1536
Large-scale methods:
Summary of MRI vs. EEG: https://imotions.com/blog/learning/research-fundamentals/eeg-vs-mri-vs-fmri-differences/
Electrophysiology methods:
Patch-clamp: https://en.wikipedia.org/wiki/Patch_clamp
Neuropixels 2.0: A miniaturized high-density probe for stable, long-term brain recordings (Steinmetz et al., 2021) https://www.science.org/doi/10.1126/science.abf4588
Calcium imaging:
Wide-Field Calcium Imaging of Neuronal Network Dynamics In Vivo (Nietz et al., 2022) https://www.mdpi.com/2079-7737/11/11/1601/pdf
Voltage imaging:
VSDI: a new era in functional imaging of cortical dynamics (Grinvald & Hildesheim, 2004) https://www.nature.com/articles/nrn1536
Optical voltage imaging in neurons: moving from technology development to practical tool (Knöpfel & Song, 2019) https://doi.org/10.1038/s41583-019-0231-4
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