Seminar by Luca Mazzucato - Mon July, 6 at 10:00am @SISSA via Bonomea 265

[Quantitative Life Sciences]

Luca Mazzucato (U. Oregon) will be visiting SISSA on Mon July, 6. For an 
overview of this research, see: https://www.mazzulab.com/research.html
He will give a talk at 10 AM, most likely in Aula 3 (TBC). Please find 
title and abstract below. Everyone is welcome to attend.

If you want to talk to Luca, please drop me a message (Francesca 
Mastrogiuseppe frmastr at sissa.it) <mailto:frmastr at sissa.it>! Luca will 
only be available in the morning. But he will be in town for the rest of 
the week, so other meeting times can be arranged.

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Control of cortical population activity with microstimulation

Closed-loop control of cortical activity is a central goal in systems 
neuroscience and clinical neuromodulation, but most approaches either 
rely on detailed circuit models that are unattainable in vivo or on 
open-loop stimulation tuned by trial and error. Here we introduce 
REACHable manifold Control (REACH-Ctrl), a data-driven brain–computer 
interface that achieves real-time control of population spiking activity 
using patterned microstimulation and multi-electrode recordings. 
REACH-Ctrl learns a finite-horizon controllability map directly from 
short training epochs in which random multi-electrode pulse sequences 
are delivered through a subset of electrodes while recording evoked 
responses. From these input-output data, it identifies the “reachable 
manifold” of population states and computes low-current microstimulation 
sequences that steer activity toward designated targets, without 
explicit knowledge of the underlying connectivity or dynamics. We 
validate REACH-Ctrl in recurrent network models and test it in macaque 
prefrontal cortex, demonstrating high control accuracy, robust across 
sessions and stimulation parameters. Geometric analyses showed that 
multi-pulse sequences traverse a well-defined reachable manifold with 
substantial, but incomplete, overlap with the intrinsic neural activity 
manifold, revealing both on- and off-manifold components of control. 
Encoding models further revealed that, in our weak-stimulation regime, 
population responses to multi-electrode sequences are well approximated 
by the linear sum of localized “stimulation fields” explaining the 
success of our linear control approach. These results demonstrate 
precise, sample-efficient control of cortical population activity with 
clinically relevant microstimulation hardware, and provide a general 
blueprint for designing perturbations for sparsely observed neural circuits.


Erica Sarnataro
Group Secretary
Quantitative Life Sciences
The Abdus Salam International Centre for Theoretical Physics (ICTP)
Trieste,  Italy
Tel. +39-040-22404623 (NEW PHONE NUMBER)
www.ictp.it/research/qls.aspx
e-mail:qls at ictp.it