Category Archives: Calcium Imaging

Protocols to check the performance of your multiphoton microscope

In an exceptionally useful paper, Lees et al. provide a set of protocols for checking the performance of your multiphoton microscope: Standardized measurements for monitoring and comparing multiphoton microscope systems (link to preprint). The paper covers the following procedures: Check … Continue reading

Posted in Calcium Imaging, Microscopy, Reviews | Tagged , , | 2 Comments

Non-linearity of calcium indicators: history-dependence of spike reporting

Calcium indicators are used to report the calcium concentration inside single cells. In neurons, calcium imaging can be used as a readout of neuronal activity (action potentials). However, some calcium indicators like GCaMP transform the calcium concentration of a cell … Continue reading

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A resource paper for building two-photon microscopes

The article discusses the challenges in learning to build microscopes, highlighting a manuscript by Schottdorf et al. that offers practical assembly instructions and rationale based on years of successful use. It emphasizes useful insights, such as design suggestions, performance compromises, and comprehensive documentation on GitHub, making it a valuable resource for researchers. Continue reading

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Spike inference with GCaMP8: new pretrained models available

Calcium imaging is only an indirect readout of neuronal activity via fluorescence signals. To estimate the true underlying firing rates of these neurons, methods for “spike inference” have been developed. They are useful to denoise calcium imaging data and make … Continue reading

Posted in Calcium Imaging, Data analysis, Imaging, machine learning, Network analysis, Neuronal activity | Tagged , , , , | 4 Comments

A collaborative review on error signals in predictive processing

Predictive processing is one of the most influential ideas from computational neuroscience for the experimental neurosciences. However, definitions of predictive processing vary broadly, to the extent that “predictive coding” is used sometimes in a very narrow sense (there are specific … Continue reading

Posted in Calcium Imaging, Data analysis, machine learning, Neuronal activity, neuroscience, Uncategorized | Tagged , , , | Leave a comment

Four interesting papers on astrocyte physiology

A review of four interesting recent papers on astrocyte neuroscience: (1) Norepinephrine Signals Through Astrocytes To Modulate Synapses (2) A spatial threshold for calcium surge (3) Network-level encoding of local neurotransmitters in cortical astrocytes, and (4) Continue reading

Posted in Calcium Imaging, Data analysis, hippocampus, Imaging, Microscopy, Neuronal activity, neuroscience, Reviews, zebrafish | Tagged , , , | 1 Comment

There is no recipe for discoveries

There is no recipe for discoveries, and there is no cookbook on how to publish a paper. But at least there are typical events and routes that are often encountered. Here, I’d like to share the trajectory of a study … Continue reading

Posted in Calcium Imaging, Data analysis, hippocampus, Imaging, machine learning, Microscopy, neuroscience, Review | Tagged , , | 8 Comments

Why your two-photon images are noisier than you expect

A gallery of calcium imaging recordings of neurons and astrocytes with single noisy frames on the left and averaged beautiful noise-free images on the right side. Continue reading

Posted in Calcium Imaging, Data analysis, hippocampus, Imaging, Microscopy, Neuronal activity, neuroscience, zebrafish | Tagged , , , , , | 22 Comments

Improving the resonant scanner’s sync signal using a phase locked loop (PLL)

Calcium imaging with two-photon point scanning is the technique to chronically record from identified neurons in the living brain of animals. The central piece of two-photon point scanning microscopes is a scan engine. This can be a complex optical device … Continue reading

Posted in Calcium Imaging, Imaging, Microscopy, neuroscience | Tagged , , | 6 Comments

Interesting papers on behavioral timescale synaptic plasticity (experiments)

Behavioral timescale synaptic plasticity (BTSP) is a form of single-shot learning observed in hippocampal place cells in mice (Bittner et al., 2015, 2017). The idea is that post-synaptic activations (“eligibility traces”) are potentiated by a dendritic plateau potential/burst (“instructive signal”) … Continue reading

Posted in Calcium Imaging, Data analysis, electrophysiology, Network analysis, Neuronal activity, Reviews | Tagged , , , | 4 Comments