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02-2017 - What an honour and incredible acknowledgment of our research - Thilo received the 2017 E.W.R. Steacie Memorial Fellowship Award with five fellow scientists in Canada and across the Natural Sciences and Engineering. This is one of the most prestigious awards for young scientists in Canada, celebrating the critical role of fundamental, basic research for driving innovation. For a write-up about Thilo's contributions see here. Thank you NSERC, and thank you Canada !! - it was an unforgettable experience to see how Canada's parliamentarians in the House of Commons acknowledged Scientists and the role of basic sciences for society, and how an impressively knowledgeable Prime Minister Trudeau and Science Minister Duncan succeeded to inspire and impress Scientists on their mission to make a difference to the lives of people in the short- and in the long-term!

02-2017 - Theta and beta frequency range coherence between anterior cingulate cortex and frontal eye field indexes the successful preparation for anti-saccades and maintenance of working memory content - with larger ACC to FEF direction of granger causal information flow! These important findings is now published in Nature Communications by Sahand Babapoor-Farrokhran and Stefan Everling with contributions from Martin Vinck and our lab - This is a particular important finding as neuronal coordination between prefrontal and anterior cingulate cortex at the identical frequency ranges characterize successful attention shifts and adjustments following errors - thus there is clear link of prefrontal attentional control signalling to the actual implementation of attentional selection in FEF (and parietal) networks - Congratulations for this major achievement ! The article Theta and beta synchrony coordinate frontal eye fields and anterior cingulate cortex during sensorimotor mapping can be downloaded here .

01-2017 -Congratulations to Ali and Mariann for the first neuropharmacological contribution from our laboratory with the article A computational psychiatry approach identifies how alpha-2A noradrenergic agonist Guanfacine affects feature-based reinforcement learning in the macaque . This study first surveys all 14 different tasks that have ever been used with Guanfacine in nonhuman primate studies and than shows in a single case study how rigorous computational reinforcement learning modelling extends existing knowledge by informing about the fundamental learning mechanisms that this drug affects during complex reversal learning. This article is particular important as it paves the way for a more formal computational approach to understand the neural effects of systemically acting psychoactive drugs like Guanfacine (which is uses in Attention Deficit Hyperactivity Disorder, mild cognitive impairment, and more). Congrats Ali and Mariann and all co-authors that made this study possible !

10-2016 - Congratulations to Ben Voloh for winning the Marian Regan prize for his MSc work on theta-gamma coupling in frontal cortex during visual attention ! The Marian Regan prize is awarded annually to one graduate student to acknowledge special accomplishments honoured by the York Centre for Vision Research community! A nice write up in the Universities media can be found here. Very well deserved !

05-2016 - The lab has a new manuscript accepted/in press on the encoding of attentional target information ! Congratulations to Steffi Westendorff for spear-heading the article Prefrontal and anterior cingulate cortex neurons encode attentional targets even when they do not bias behavior! We show that about two third of neurons in prefrontal and anterior cingulate cortex encode putative attention targets in their firing rate even if they do not bias behaviour (while one third of the neuron population encode attention targets only when they bias behaviour in correct trials). This finding is consistent with the common belief that prefrontal and anterior cingulate cortex represent multiple objects that could be relevant at any moment in time in order to gain flexibility on that to choose at particular time points to guide action. Thus, instead of being bound to encode only information that influences behaviour, the representations are selectively encoding what “could be” relevant. Some procedures about the State Space Analysis of the Population Dynamics of this manuscript will be made available online in a matlab script to facilitate similar analysis in other labs (see Analysis → Local).

04-2016 - Humans vary in how and how fast they learn the relevance of object features in a new environment/context, especially when there is some uncertainty about the relevance. What is it that makes some humans learn object relevance faster than others in such a situation ? We have now a powerful answer with quantitative comparisons of different reinforcement learning model schemas: In a new publication we have identified that subjects who learn fast successfully apply pre-learned strategies, or rules, while other subjects who tend to learn slower or fail to learn do not identify rules as heuristic. This work, spearheaded by PhD Matt Balcarras and entitled A flexible mechanism of rule selection enables rapid feature-based reinforcement learning is now published in Frontiers in Neuroscience.

03-2016 - to Ben to win the York University 3 minute thesis competition in presenting his MSc graduation work ! Here is the University's press release about the 2016 YorkU 3MT Winner ! Good luck from the laboratory when moving to the provincial level competition (still with only 3 minutes…for the whole thesis).

03-2016 - Does a reset of ongoing brain activity fluctuations play a role for communication in brain networks? A careful and very broad review of the literature suggests that it does across all levels from cell activities to small circuits, to multi-circuit networks: Phase resets seem to set the critical 'neural context' for efficient network encoding of relevant information during attention and goal-directed behaviour. Spearheaded by Ben Voloh in the lab, the evidence is now reviewed in an article published at Frontiers in Systems Neuroscience, online available as pdf.

11-2015 - Thilo gave a a 'Cutting-Edge Series' Lecture on Brain Networks and Mental Illness at the Toronto Public Libraries. This was a great exchange of science and public with a fully packed, engaged auditorium. Here the slideshow as pdf download: 'Brain Networks and Mental Illness Slides', with an Appendix listing additional www links and resources allowing to follow up on the topics.

11-2015 - http:// intriguing Attention Workshop series at Rovereto, Italy, focused this year on the role of rhythmic activities for attentional selection and hosted Thilo to represent a prefrontal/anterior cingulate perspective on these topics. This was an incredibly interesting event dedicated to elucidate the neurobiology of attentional mechanisms. Highly recommended !

10-2015 - Our integrative review on Long-Range Attention Networks: Circuit Motifs Underlying Endogenously Controlled Stimulus Selection) is now online at Trends in Neurosciences ! This review surveys the brain networks controlling versus implementing attention through phase synchronizing long-range networks. We survey how Dynamic Circuit Motifs subserve the long-range gating and integration of relevant information during attention.

08-2015 - Very good news for Mariann and the lab from the Journal of Neuroscience which accepted the manuscript Inter-areal spiketrain correlations of anterior cingulate and dorsal prefrontal cortex during attention shifts by Oemisch, Westendorff, Everling and Womelsdorf. Congratulations to Mariann and Steffi and a huge thanks to Stefan Everling for enabling, facilitating contributing and supporting this ! Here the significance statement from the paper: Our manuscript identifies inter-areal spiketrain correlations between primate anterior cingulate and dorsal prefrontal cortex during a period where attentional stimulus selection is likely controlled by these very same circuits. Inter-areal correlations emerged during the covert attention shift to one of two peripheral stimuli, proceeded on a slow 50-200ms time scale and occurred between putative pyramidal and putative interneurons. Spiketrain correlations emerged particularly for cell pairs tuned to similar contralateral target locations, thus indexing the inter-areal coordination of attention relevant information. These findings characterize a possible way by which prefrontal and anterior cingulate cortex circuits implement their control functions through coordinated firing when macaque monkeys select and monitor relevant stimuli for goal-directed behaviors. (for reprints please email).

07-2015 - laboratory received excellent news from The Canadian Institutes of Health Research (CIHR) - The core of the lab's research will continue to be supported by CIHR, following the mandate '… to excel … in the creation of new knowledge [in the biomedical sciences] and its translation into improved health for Canadians'. This support is especially important as the overall research funding situation remains extremely challenging with severely limited resources allocated to foundational research.

07-2015 - The lab's second translational paper is online with the tremendous and generous help of Prof. Taufik Valiante ! We found that successful detection of a subtle (near-threshold) event at an unpredictable location is preceded by enhanced long-range coherence at a characteristic beta frequency range - between those brain areas (IFJ and TPJ) implicated in establishing top-down expectancies and maintaining the selection of 'attentional sets' ! Thanks to Cristiano and the whole group of authors helping with testing patients with intractable epilepsy on a demanding cognitive task. We ll never forget the patients dedication and Dr. Valiante's drive that was so instrumental to bring this to a success ! The linked pdf is available via Inferior-frontal cortex phase synchronizes with the temporal-parietal junction prior to successful change detection.

07-2015 - The lab whole heartedly congratulates Ben Voloh for a successful MSc graduation. This is very well deserved with a milestone achievement in the form of a PNAS article on theta - gamma phase amplitude coupling across prefrontal and anterior cingulate cortex for successful attention shifts. Incredibly well done - we assure the thirteen supplementary results to validate the projects' conclusions will not be forgotten!

06-2015 - Our manuscript on the functional importance of theta - gamma phase amplitude coupling across prefrontal and anterior cingulate cortex for successful attention shifts is now online at PNAS. This is a huge achievement from Ben who finishes an ambitious MSc project with this contribution! The manuscript shows that when we covertly select a stimulus for prioritized processing (this is typically called “attention”), there are 3-5 cycles of theta rhythmic activities in the prefrontal and anterior cingulate cortex. This low frequency fluctuation synchronizes high frequency gamma bursts across multiple cortical subfields. The paper shows that this theta-gamma coordination is only evident when attention succeeds and likely originates in mechanisms underlying cue-triggered phase resets. Most of the analysis code (cross frequency coupling measures, etc.) used in this manuscript is available online via Analysis [Local].

06-2015 - Congratulations from the whole laboratory to now-Dr. Matt Balcarras for a successful defence in Biology of his PhD thesis “Reinforcement Learning describes the computational and neural processes underlying flexible learning of values and attentional selection” ! This is a milestone achievement after very hard work on ambitious projects!

05-2015 - 2015 BrainDay at Waterloo University hosted Thilo for a lecture for the neuroscience section. Brainday is a highly inspiring event organized by the Centre for Theoretical Neuroscience at Waterloo and the University to discuss brain topic from four different fields in a unifying daylong setting (Psychology, Philosophy, Systems Neuroscience, Theoretical Neuroscience). The talk at Brainday is freely available as youtube video and is entitled Cells and Circuits Coordinating Attention: Dynamic Circuit Motifs in Primate Prefrontal Cortex.

03-2015 - Public Lecture on “Brain Networks and Mental Illness”. http://science.yorku.caAn engaged audience made a Public Lecture on “Brain Networks and Mental Illness” a huge success and a true exchange of science and community. Thilo gave the lecture for the Toronto Public Library which organized these meeting points between scientists and the community - supported by the Faculty of Science at York University. This was a remarkable experience with a fully packed auditorium and lots of discussion about scientific, political and community based matters linked to brain disorders and the extraordinary role of basic science to advance this field.

02-2015 - Salva's cell classification paper Mapping of functionally characterized cell classes onto canonical circuit operations in primate prefrontal cortex is published in the Journal of Neuroscience. This paper shows how cells in the prefrontal microcircuit segregate into seven distinct functional cell classes during actual goal directed behaviour. This is a critical milestone for the endeavour to identify how specific cell types contribute to different functional networks. We found that different classes of pyramidal cells and putative interneurons show synchronization preferences to theta, to beta, or did not engage in rhythmic firing, suggesting different functional roles for these cells. Importantly, the matlab scripts for the data-driven (objective and cross validated) functional clustering approach, and the cell type classification procedure are available for download with tutorial like documentation (see matlab analysis tools for detail).

11-2014 - The recipient for this years Petro Canada Young Innovator Award is coming from our lab… Thilo received this award “… for his research bridging the diverse fields of computational and cellular neuroscience.”. You can read the media release with some quotes about the work's impact and background information here: YFile Media Release.

10-2014 - Our manuscript on coordination of attention information through bursts and burst synchronization during attentional states is published at Current Biology. The findings in this paper are intriguing as they suggest that mechanisms underlying burst firing in inhibitory cells (and in pyramidal cells) are sources for the control of attention. In other words, we seem to have found a window into how cell specific firing mechanisms relate the formation of large-scale attention networks! pdf.

08-2014 - Our review article on Dynamic Circuit Motifs that support gating, gain control and integration of synaptic information through periodically synchronized activity is out at Nature Neuroscience !

08-2014 - Completed tutoring for a great audience of students in Minnesota for the 2014 Summer School in Computational Sensory-Motor Neuroscience (CoSMo 2014). This is an excellent Summer School to learn about Baysian Learning and how the brain implements control processes during sensori-motor integration and decision making. Courtesy to Prof. Paul Schrater (Minnesota) and Prof. Gunnar Blohm (Queens) who organized this event and made this a very rewarding experience. All lecture and tutorial material is freely available on the internet, linked here.

04-2014 - The results of Chen's MSc project just got published in Cerebral Cortex! Chen found… that Anterior cingulate cortex cells identify process-specific errors of attentional control prior to transient prefrontal-cingulate inhibition This shows with a data driven functional mapping approach that the ACC is tracking attentional processes and how correct they are - this is a very impressive result that clarifies how control demands are monitored in the brain ! - and an incredibly nice accomplishment for a MSc project ! Here the link to the paper pdf

02-2014 - Our first translational research paper is out! The study about choice predictive Beta coherence within human ventromedial prefrontal cortex is online at NeuroImage with a 2014 publication date. Tremendous thanks to Dr. Andres Lozano for enabling this !

03-2013 - FieldTrip Workshop at York University, Toronto. We organized in 03-2013 a Matlab Analysis Workshop based on the Fieldtrip open source toolbox. The course aimed at introducing basic and advanced analysis of spike- and spike-LFP analysis, statistical approaches and connectivity analysis. Core features of the workshop: Experts lead lectures on individual topics. Hands-On sessions on matlab scripts allow to run tutorial data and ‘own-data‘ with help and guidance from experienced tutors. Short Project Presentations from Attendees and Tutors provide the opportunity to present and discuss applications of analysis approaches. Most of the tutorial scripts are available online at the fieldtrip website. The workshop featured lectures from three experts in spike and LFP analysis:

More then 45 graduate students, postdocs (and PI's) from 7 Universities in Canada (and 1 from the US !), see some photos of the workshop.

2013 - The new lab website is online (and - well - still under further construction …)

newsroom.txt · Last modified: 2017/02/12 16:31 by Thilo Womelsdorf