Cholinergic Control of Chaos and Evidence
Sensitivity in a Neocortical Model of Perceptual
Decision-Making
Adrián F. Amil 1,2 , Jordi-Ysard Puigbò 1,5(B) , and Paul F. M. J. Verschure 1,3,4
1 Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
pverschure@ibecbarcelona.eu
2 Pompeu Fabra University (UPF), Barcelona, Spain
3 Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
4 Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
5 BitMetrics, Barcelona, Spain
Abstract. Perceptual decision-making in the brain is commonly modeled as a
competition among tuned cortical populations receiving stimulation according to
their perceptual evidence. However, the contribution of evidence on the decisionmaking process changes through time. In this regard, the mechanisms controlling
the sensitivity to perceptual evidence remain unknown. Here we explore this issue
by using a biologically constrained model of the neocortex performing a dualchoice perceptual discrimination task. We combine mutual and global GABAergic
inhibition, which are differentially regulated by acetylcholine (ACh), a neuromodulator linked to enhanced stimulus discriminability. We find that, while mutual
inhibition determines the phase-space separation between two stable attractors
representing each stimulus, global inhibition controls the formation of a chaotic
attractor in-between the two, effectively protecting the weakest stimulus. Hence,
under low ACh levels, where global inhibition dominates, the decision-making
process is chaotic and less determined by the difference between perceptual evidences. On the contrary, under high ACh levels, where mutual inhibition dominates, the network becomes very sensitive to small differences between stimuli.
Our results are in line with the putative role of ACh in enhanced stimulus discriminability and suggest that ACh levels control the sensitivity to sensory inputs by
regulating the amount of chaos.
Keywords: Acetylcholine · Cortical model · Decision-making · Chaos
The current work has received funding from H2020-EU project VirtualBrainCloud, ID:826421.
In addition, Adrián F. Amil is supported by a FI-AGAUR2020 scholarship from the Generalitat
de Catalunya.
© Springer Nature Switzerland AG 2020
V. Vouloutsi et al. (Eds.): Living Machines 2020, LNAI 12413, pp. 92–96, 2020.
https://doi.org/10.1007/978-3-030-64313-3_10
Sensitivity in a Neocortical Model of Perceptual
Decision-Making
Adrián F. Amil 1,2 , Jordi-Ysard Puigbò 1,5(B) , and Paul F. M. J. Verschure 1,3,4
1 Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain
pverschure@ibecbarcelona.eu
2 Pompeu Fabra University (UPF), Barcelona, Spain
3 Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
4 Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
5 BitMetrics, Barcelona, Spain
Abstract. Perceptual decision-making in the brain is commonly modeled as a
competition among tuned cortical populations receiving stimulation according to
their perceptual evidence. However, the contribution of evidence on the decisionmaking process changes through time. In this regard, the mechanisms controlling
the sensitivity to perceptual evidence remain unknown. Here we explore this issue
by using a biologically constrained model of the neocortex performing a dualchoice perceptual discrimination task. We combine mutual and global GABAergic
inhibition, which are differentially regulated by acetylcholine (ACh), a neuromodulator linked to enhanced stimulus discriminability. We find that, while mutual
inhibition determines the phase-space separation between two stable attractors
representing each stimulus, global inhibition controls the formation of a chaotic
attractor in-between the two, effectively protecting the weakest stimulus. Hence,
under low ACh levels, where global inhibition dominates, the decision-making
process is chaotic and less determined by the difference between perceptual evidences. On the contrary, under high ACh levels, where mutual inhibition dominates, the network becomes very sensitive to small differences between stimuli.
Our results are in line with the putative role of ACh in enhanced stimulus discriminability and suggest that ACh levels control the sensitivity to sensory inputs by
regulating the amount of chaos.
Keywords: Acetylcholine · Cortical model · Decision-making · Chaos
The current work has received funding from H2020-EU project VirtualBrainCloud, ID:826421.
In addition, Adrián F. Amil is supported by a FI-AGAUR2020 scholarship from the Generalitat
de Catalunya.
© Springer Nature Switzerland AG 2020
V. Vouloutsi et al. (Eds.): Living Machines 2020, LNAI 12413, pp. 92–96, 2020.
https://doi.org/10.1007/978-3-030-64313-3_10