• matlab
• calcium
• astrocytes
• calcium imaging
• 2-photon microscopy
• BDNF
• perirhinal cortex
• memory
• computational neuroscience

Calcium ion (Ca2+) is a second messenger that plays a pivotal role in the physiology of the cell.
Excitable cells, such as neurons and glia, are known to finely regulate their intracellular Ca2+
concentration with a very precise spatio-temporal resolution, giving rise to complex signals.
Being able to decipher these signals implies the opportunity to exploit a full-fledged "window
with a view" on the life of the brain.
During my internship, I contributed to the development of a novel MATLAB-written software,
named Image Gateway, that has been devised with the simple aim of allowing unbiased,
virtually ROI-free analyses of calcium imaging acquisitions. The two main purposes of Image
Gateway are, in extreme synthesis, that of (i) automatically extracting "interesting" clusters of
Ca2+ activity – conceived as spatio-temporal columns that encompass high fluctuations of Ca2+
ΔF/F activity –, and (ii) automatically computing a cross-correlation analysis on the ΔF/F time
series extracted from these clusters. A very wide range of different parameters and diverse
pipelines are at the user’s disposal, making the overall analysis process highly customizable and
quite fast. On top of that, Image Gateway is virtually independent of the neurobiological
problem. The software can in fact be launched regardless of the kind of microscopy, and it can
carry out analyses either at the single-cell level or at multiple-cells level – virtually on any cell type.
For this thesis, I report the use of Image Gateway for the study and the characterization of
intracellular Ca2+ microdomains present within the thin processes of astrocytes – a type of glial
cells which is known to finely oversee the neuronal computation, as well as plasticity
phenomena – whose activity was recorded in slices of mouse perirhinal cortex by means of two-
photon microscopy. The results allowed to unveil the stochastic, virtually neuronal-independent
behaviour of perirhinal cortex astrocytic Ca2+ microdomains, which were previously shown to be
necessary for synaptic LTP stabilization and maintainance through pro-BDNF/BDNF recycling.
These findings suggest the importance of auto-regulatory mechanisms, operated within the astrocytic peri-synaptic territory itself, which might subtend an unexpected functional drive at
the basis of episodic memory formation.