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Hello Everyone,</div>
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<div class="elementToProof"><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);">Just a reminder that our first CTN colloquium of the term will be next Tuesday, February
6 starting at 3:30 p.m. in E5-2004.</span></div>
<div><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);">The speaker is
<a href="https://sites.google.com/view/lnsbsp/home" id="OWAfec04485-666d-744f-7b6b-a1ba54b66c16" class="OWAAutoLink" title="https://sites.google.com/view/lnsbsp/home">
Milad Lankarany</a> from the Krembil Research Institute.</span></div>
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<div><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);"><b>Title:</b> Using Computational Neuroscience and Neuromodulation Techniques to Uncover Mechanisms of Neural
Systems</span></div>
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<div><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);"><b>Abstract:</b> Deep brain stimulation, as an invasive neuromodulation technique, has been successfully used
to reduce symptoms of movement disorders by delivering electrical pulses to the substructures of the basal ganglia and thalamus. Existing efforts to understand the mechanisms of action of DBS rely on detecting biomarkers during (or after) delivering clinically
approved high-frequency pulses and assessing their clinical outcomes. However, less consideration has been given to how DBS modulates information processing in the human brain. Specifically, it is not yet discovered how modulated neural activities observed
in a sub-cortical region represent dynamics of underlying circuitry. Building on our published data of in-vivo single-unit recordings in patients with Essential Tremor (n = 20), we discovered that neuronal dynamics (in the sense of instantaneous firing rate)
of thalamic ventral intermediate nucleus (Vim) in response to various frequencies of deep brain stimulation (DBS) can be explained by Balanced Amplification mechanism, an established theoretical framework that suggests the large amplification of excitation
— caused by either strong external input or positive recurrent circuitry — can be balanced by strong feedback inhibition. We developed a network rate model, together with a sequential optimization algorithm, that accurately reproduces the instantaneous firing
rate of Vim neurons, the primary surgical target of DBS for reducing symptoms of essential tremor, in response to low- and high-frequency DBS. Our study revealed that the computer simulation of a single population of Vim neurons (appeared in our recent publication
PMID: 37140523) cannot capture the dynamics of the firing rate, thus the presence of other neuronal populations is essential to track the firing rate reliably and mechanistically. Interestingly, our work suggests, in an unsupervised manner, that the presence
of an inhibitory neuronal population is necessary to replicate Vim firing rates across different DBS frequencies. We anticipate that our study provides a conceptual modeling framework to uncover mechanisms of information processing in different DBS-modulated
sub-cortical regions in the human brain.</span></div>
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<div><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);">Hope to see you there!</span></div>
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<div><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);">Regards,</span></div>
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<div><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 11pt; color: rgb(0, 0, 0);">Sue Ann</span></div>
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<p style="margin-top: 0px; margin-bottom: 0px;">_______________________________________________</p>
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<p style="margin-top: 0px; margin-bottom: 0px;">Dr. Sue Ann Campbell (she/her)</p>
<p style="margin-top: 0px; margin-bottom: 0px;">Professor and University Research Chair</p>
<p style="margin-top: 0px; margin-bottom: 0px;">Department of Applied Mathematics</p>
<p style="margin-top: 0px; margin-bottom: 0px;"><a href="https://uwaterloo.ca/centre-for-theoretical-neuroscience/" id="OWAd99c2ff9-7457-d2ad-d55b-56dfe607bf5f" class="OWAAutoLink" title="https://uwaterloo.ca/centre-for-theoretical-neuroscience/" style="margin-top: 0px; margin-bottom: 0px;">Centre
for Theoretical Neuroscience</a></p>
<p style="margin-top: 0px; margin-bottom: 0px;">Associate Dean, Research</p>
<p style="margin-top: 0px; margin-bottom: 0px;">Faculty of Mathematics</p>
<p style="margin-top: 0px; margin-bottom: 0px;">University of Waterloo</p>
<p style="margin-top: 0px; margin-bottom: 0px;">Waterloo ON N2L 3G1</p>
<p style="margin-top: 0px; margin-bottom: 0px;"><a href="https://www.math.uwaterloo.ca/~sacampbe/" id="OWA1b0a3bf4-725b-ef8f-42b0-0c4526575cfb" class="OWAAutoLink" style="margin-top: 0px; margin-bottom: 0px;">https://www.math.uwaterloo.ca/~sacampbe/</a></p>
<p style="margin-top: 0px; margin-bottom: 0px;">President, <span style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">
<a href="https://caims.ca/" id="OWAadada4ec-68bc-60be-9591-d6c6d8286fab" class="OWAAutoLink" title="https://caims.ca/" style="margin-top: 0px; margin-bottom: 0px;">Canadian Applied and Industrial Mathematics Society</a></span></p>
<p style="margin-top: 0px; margin-bottom: 0px;"><br>
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<p style="margin-top: 0px; margin-bottom: 0px;"><i>I acknowledge that I live and work on the traditional territory of the Chonnonton, Anishinaabeg and Haudenosaunee peoples. The University of Waterloo main campus is located on the Haldimand tract, the land
granted to the Six Nations that includes six miles on each side of the Grand River.</i></p>
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