Contact

Dr. Yusuke Murayama

Adresse: Spemannstr. 38
72076 Tübingen
Raum Nummer: 253
Tel.: 07071 601 663
Fax: 07071 601 652
E-Mail: yusuke.murayama

 

Bild von Murayama, Yusuke, Dr.

Yusuke Murayama

Position: Wissenschaftler  Abteilung: Logothetis

Introduction

In our efforts study the brain simultaneously at different spatiotemporal scales we have long been developing and optimizing two powerful methodologies. These are first, in vivo connectivity based on MR-detectable paramagnetic transsynaptic tracers, such as manganese, e.g.(Saleem et al., 2002, Murayama et al., 2006, Eschenko et al., 2010), and second, direct electrical stimulation and fMRI combined (DES-fMRI) (Tolias et al., 2005, Logothetis et al., 2010). The latter permits the investigation of many different large-scale interactions, including the organization of projective fields, large-scale effects of local synaptic plasticity changes, and the spatiotemporal profile of neuromodulatory effects induced by diffuse ascending systems. Yet, our most recent pilot physiology-MRI study examining global signal propagation following electrical stimulation has demonstrated that DES most likely silences all cortical areas receiving direct input from the fibers that they excite (Logothetis et al., 2010). Together with results from previous electrophysiology studies, this finding is thought to reflect the synaptic organization of microcircuits and their response to an unnatural spatiotemporal input organization. Specifically, optimal operation of recurrent microcircuits is only ensured with spatio-temporally structured input patterns that respect synaptic delays. ES violates this principle and consequently silences the output of neocortex. To better understand feedforward signal propagation for spatiotemporally blurred inputs, we have conducted two more series of experiments.

The first study aimed to examine whether unstructured whole-field visual stimulation may to some extent resemble the pattern of signal. We used whole-field luminance flicker as stimulus and recorded from areas V1 and V2 during EPI MR imaging. In the second study we have started a systematic mapping of thalamus by local microstimulation and imaging. The aim of this investigation is to map cortico-subcortico-cortical pathways by means of ortho- and antidromic stimulation and try to understand the logic of the replication principle, namely the existence of a cortico-thalamo-cortical connection for any given cortico-cortical connection of two points, each in one cortical area. We stimulate the pulvinar but we also record spontaneous activity and study locally generated characteristic events that may be related to thalamo-cortical communication.

 

Methods

Recording and microstimulation hardware, including electrodes and microdrives, were developed at the Max Planck Institute for Biological Cybernetics. Recording chambers and head holders were positioned stereotaxically on the basis of individual, high-resolution MRI. Stimulation sites were selected so as to ensure reliable electrically evoked BOLD activation on the operculum of the brain. Visual stimuli (structured stimuli or whole-field luminance flicker) were presented binocularly, initially with our own custom-made MR-compatible visual stimulator. Electrical microstimulation was performed with a custom-built constant current source. Current amplitude, pulse duration, train duration and stimulation frequency were controlled digitally using our own TCL-based software and a QNX (Canada) real time operating system.

 

Results and Initial Conclusions

The stimulation results were presented in detail in a recent publication (Logothetis et al., 2010). The response to luminance flicker was surprising indeed. Figure 1 shows the maps and Figure 2 the temporal dynamic of the BOLD and neural responses to two types of stimulation: structured (counterphase pinwheel) and full-field luminance flicker. Striking and consistence was the patent deactivation of V2. V1 showed PBR in some animal and NBR in others. Physiological responses often showed continuation of stimulus-induced modulation, albeit with a strongly reduced baseline activity. It follows that unstructured, full-field luminance stimulations, just like the electrical stimulation, blurs the normal spatiotemporal input patterns in cortex and strong disrupts signal propagation. Our current experiments in thalamus yielded the first patterns of cortical activation (work in progress). Characteristic is the widespread activation that is expected given the parallel projections of this nucleus to the entire cortex.

 

BOLD responses to counter-phase and Full-Field Luminance Flicker

Figure 1: BOLD responses to counter-phase and Full-Field Luminance Flicker. The left plots shows response to counterphase flicker. As expected there is strong V1 and V2 activation accompanied by sustained negative BOLD (NBR) in non-stimulated areas.

 

Time course of BOLD and of neural responses to counter-phase and Full-Field Luminance Flicker.

Figure 2: Time course of BOLD and of neural responses to counter-phase and Full-Field Luminance Flicker. Top row shows responses to structured flicker. Red and Blue curves are BOLD responses in V1 and V2 respectively. Peristimulus histograms show multiunit responses in V1 (left) and V2 (right). Bottom row: same conventions but for full-field luminance flicker.

 

 

Collaborations

In the aforementioned studies I have been collaborating with Mark Augath, Josina Goense and Hellmut Merkle on MR in MR imaging, with Alexander Rauch and Nikos K. Logothetis in neuroscientific matters and data analysis, and with Axel Oeltermann in developing all the hardware required to perform the experiments (see details in publications).

 

References

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Zeige Zusammenfassung

Poster (36):

Mazzoni A, Kayser C, Murayama Y, Martinez J, Quiroga RQ, Logothetis NK und Panzeri S (Juni-2010): Primary Visual Cortex Encodes Complementary Information about Naturalistic Movies at Different Temporal Scales, AREADNE 2010: Research in Encoding And Decoding of Neural Ensembles, Santorini, Greece.
Biessmann F, Murayama Y, Meinecke FC, Logothetis NK und Müller K-R (Juni-2010): Spatio-Temporal Coupling between Neural Activity and Bold Response in Primary Visual Cortex, AREADNE 2010: Research in Encoding And Decoding of Neural Ensembles, Santorini, Greece.
Sultan FR, Augath M, Hamodeh S, Murayama Y, Thier P und Logothetis NK (Oktober-2009): Revealing polysynaptic propagation of excitation by microstimulation-fMRI of the deep cerebellar nuclei, 39th Annual Meeting of the Society for Neuroscience (Neuroscience 2009), Chicago, IL, USA.
Sultan F, Augath M, Murayama Y, Hamodeh S, Thier P und Logothetis NK (März-2009): Revealing Excitable Subcortical Networks by Microstimulationf-MRI of the Deep Cerebellar Nuclei, 8th Göttingen Meeting of the German Neuroscience Society, 32nd Göttingen Neurobiology Conference, Göttingen, Germany.
Sultan F, Murayama Y, Hamodeh S, Saleem KS und Logothetis NK (November-2008): A flattened representation of the neocortical areas of Macaca mulatta as obtained from combined MRI and histology, 38th Annual Meeting of the Society for Neuroscience (Neuroscience 2008), Washington, DC, USA.
Belitski A, Gretton A, Magri C, Murayama Y, Montemurro M, Logothetis NK und Panzeri S (November-2007): A time/frequency decomposition of information transmission by LFPs and spikes in the primary visual cortex, 37th Annual Meeting of the Society for Neuroscience (Neuroscience 2007), San Diego, CA, USA.
Canals S, Beyerlein M, Keller AL, Murayama Y und Logothetis NK (Mai-23-2007): In vivo brain connectivity: optimization of manganese enhanced MRI for neuronal tract tracing, 2007 Joint Annual Meeting ISMRM-ESMRMB, Berlin, Germany.
Canals S, Beyerlein M, Keller AL, Murayama Y und Logothetis NK (April-2007): In vivo brain connectivity: optimization of manganese enhanced MRI for neuronal tract tracing, 7th Meeting of the German Neuroscience Society, 31st Göttingen Neurobiology Conference, Göttingen, Germany, Neuroforum, 13(Supplement) 1221.
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Gretton A, Belitski A, Murayama Y, Schölkopf B und Logothetis NK (November-2005): Kernel methods for dependence testing in LFP-MUA, 35th Annual Meeting of the Society for Neuroscience (Neuroscience 2005), Washington, DC, USA.
Fust A, Pauls J, Augath M, Oeltermann A, Murayama Y und Logothetis NK (November-2003): The influence of anaesthetic agents on spiking and subthreshold activity in visual cortex revealed by electrophysiology and high-resolution functional MRI, 33rd Annual Meeting of the Society for Neuroscience (Neuroscience 2003), New Orleans, LA, USA.
Shmuel A, Augath MA, Oeltermann A, Pauls J, Murayama Y und Logothetis NK (Juni-2003): The Negative BOLD Response in Monkey V1 Is Associated with Decreases in Neuronal Activity, Ninth Annual Meeting of the Organization for Human Brain Mapping (HBM 2003), New York, NY, USA, NeuroImage, 19(2 Supplement) e567-e568.
Haiss F, Leopold DA, Murayama Y und Logothetis NK (Februar-2002): Dynamics of brain state transitions during anesthetic induction in the monkey, 5. Tübinger Wahrnehmungskonferenz (TWK 2002), Tübingen, Germany.
Leopold DA, Murayama Y und Logothetis NK (November-2001): Determinants of neural activity covariation in macaque visual cortex under different behavioral states, 31st Annual Meeting of the Society for Neuroscience (Neuroscience 2001), San Diego, CA, USA.
Murayama Y, Leopold DA und Logothetis NK (November-2001): Perception-related neural activity in the temporal cortex of monkeys under different conscious states, 31st Annual Meeting of the Society for Neuroscience (Neuroscience 2001), San Diego, CA, USA.
Leopold DA, Murayama Y und Logothetis NK (November-2000): Intra- and interareal covariation of neural activity during multistable perception in the monkey, 30th Annual Meeting of the Society for Neuroscience (Neuroscience 2000), New Orleans, LA, USA.
Murayama Y, Leopold DA und Logothetis NK (November-2000): Neural activity during binocular rivalry in the anesthetized monkey, 30th Annual Meeting of the Society for Neuroscience (Neuroscience 2000), New Orleans, LA, USA.
Wang Y, Fujita I und Murayama Y (Juli-1996): Contribution of GABAergic inhibition to stimulus selectivity for object features in the inferior temporal cortex, 19th Annual Meeting of the Japan Neuroscience Society, Kobe, Japan, Neuroscience Research, 25(Supplement 1) S193.
Murayama Y, Fujita I und Kato M (Juli-1996): Long-term potentiation and depression in the adult monkey neocortex, 19th Annual Meeting of the Japan Neuroscience Society, Kobe, Japan, Neuroscience Research, 25(Supplement 1) S239.
Suma C, Murayama Y und Oda Y (Dezember-1993): Long-lasting potentiation at the central inhibitory connections studied by unitary postsynaptic potential, 17th Annual Meeting of the Japan Neuroscience Society, Nagoya, Japan, Neuroscience Research Supplements, 18 S233.

Vorträge (8):

Logothetis NK, Murayama Y, Ramirez-Villegas J, Besserve M und Evrard H (November-16-2016) Abstract Talk: PGO wave-triggered functional MRI: mapping the networks underlying synaptic consolidation, 46th Annual Meeting of the Society for Neuroscience (Neuroscience 2016), San Diego, CA, USA(670.12).
Kaplan R, King J, Koster R, Adhikari MH, Hindriks R, Murayama Y, Penny WJ, Mantini D, Burgess N, Logothetis NK, Deco N und Friston KJ (Juli-18-2016) Abstract Talk: Relating rapid mental simulation to past experience, 6th International Conference on Memory (ICOM-6), Budapest, Hungary 59.
Logothetis NK, Eschenko O, Murayama Y, Augath M, Steudel T, Evrard HC, Besserve M und Oeltermann A (Juli-2013) Keynote Lecture: Studying large-scale brain networks: electrical stimulation and neural-event-triggered fMRI, Twenty-Second Annual Computational Neuroscience Meeting (CNS*2013), Paris, France, BMC Neuroscience, 14(Supplement 1) 1.
Mazzoni A, Kayser C, Murayama Y, Martinez J, Quiroga RQ, Logothetis NK und Panzeri S (November-1-2010) Abstract Talk: Primary Visual Cortex Encodes Complementary Information About Naturalistic Movies at Different Temporal Scales, 9th International Workshop Neural Coding (NC 2010), Limassol, Cyprus 69-70.
Biessmann F, Meinecke FC, Murayama Y, Logothetis NK und Müller KR (Oktober-2010) Abstract Talk: Comparison of Mass-Univariate, Unimodal and Multivariate Multimodal Analysis Methods for Neurovascular Coupling Analysis, Bernstein Conference on Computational Neuroscience 2010, Berlin, Germany, Frontiers in Computational Neuroscience, 2010(Conference Abstract: Bernstein Conference on Computational Neuroscience).
Mazzoni A, Kayser C, Murayama Y, Martinez J, Quiroga RQ, Logothetis NK und Panzeri S (Oktober-2010) Abstract Talk: Neurons in primary visual cortex encode naturalistic visual information using multiple temporal scales, Bernstein Conference on Computational Neuroscience 2010, Berlin, Germany, Frontiers in Computational Neuroscience, 2010(Conference Abstract: Bernstein Conference on Computational Neuroscience).
Logothetis NK, Sultan F, Murayama Y, Augath M, Steudel T und Oeltermann A (Oktober-2006) Abstract Talk: Microstimulation and fMRI in anesthetized and alert monkeys: Conditions for transsynaptic BOLD activation, 36th Annual Meeting of the Society for Neuroscience (Neuroscience 2006), Atlanta, GA, USA(114.10).
Oda Y, Murayama Y, Suma C und Morita M (Dezember-1994) Abstract Talk: Long-term potentiation at inhibitory synapses of the goldfish Mauthner cell induced by pairing postsynaptic depolarization with presynaptic activity, 18th Annual Meeting of the Japan Neuroscience Society, Tokyo, Japan, Neuroscience Research Supplements, 19 S34.
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Last updated: Montag, 22.05.2017