Benjamin A Suter

• Ph. D.
• PostDoc Position at Institute of Science and Technology (IST) Austria

Primary motor (M1) and secondary somatosensory (S2) cortices, although anatomically and functionally distinct, share an intriguing cellular component: corticospinal neurons (CSP) in layer 5B. Here, we investigated the long-range circuits of CSPs in mouse forelimb-M1 and S2. We found that interareal projections (S2 → M1 and M1 → S2) monosynaptically...

Corticospinal pyramidal neurons mediate diverse aspects of motor behavior. We measured spike-related electrophysiological properties of identified corticospinal neurons in primary motor cortex slices from young adult mice. Several consistent features were observed in the suprathreshold responses to current steps: 1) Corticospinal neurons fired rela...

Physiological measurements in neuroscience experiments often involve complex stimulus paradigms and multiple data channels. Ephus (http://www.ephus.org) is an open-source software package designed for general-purpose data acquisition and instrument control. Ephus operates as a collection of modular programs, including an ephys program for standard...

Motor cortex is a key brain center involved in motor control in rodents and other mammals, but specific intracortical mechanisms at the microcircuit level are largely unknown. Neuronal expression of hyperpolarization-activated current (I(h)) is cell class specific throughout the nervous system, but in neocortex, where pyramidal neurons are classifi...

Understanding cortical function requires studying multiple scales: molecular, cellular, circuit, and behavioral. We develop a multiscale, biophysically detailed model of mouse primary motor cortex (M1) with over 10,000 neurons and 30 million synapses. Neuron types, densities, spatial distributions, morphologies, biophysics, connectivity, and dendri...

Understanding cortical function requires studying its multiple scales: molecular, cellular, circuit and behavior. We developed a biophysically detailed multiscale model of mouse primary motor cortex (M1) with over 10,000 neurons, 30 million synapses. Neuron types, densities, spatial distributions, morphologies, biophysics, connectivity and dendriti...

Understanding cortical function requires studying multiple scales: molecular, cellular, circuit, and behavioral. We develop a multiscale, biophysically detailed model of mouse primary motor cortex (M1) with over 10,000 neurons and 30 million synapses. Neuron types, densities, spatial distributions, morphologies, biophysics, connectivity, and dendri...

Foreword from the editors. We hosted four keynote speakers: Wolf Singer, Bill Bialek, Danielle Bassett, and Sonja Gruen. They enlightened us about computations in the cerebral cortex, the reduction of high-dimensional data, the emerging field of computational psychiatry, and the significance of spike patterns in motor cortex. From the submissions,...

Pattern separation is a fundamental brain computation that converts small differences in input patterns into large differences in output patterns. Several synaptic mechanisms of pattern separation have been proposed, including code expansion, inhibition and plasticity; however, which of these mechanisms play a role in the entorhinal cortex (EC)–den...

Rigorous investigation of synaptic transmission requires analysis of unitary synaptic events by simultaneous recording from presynaptic terminals and postsynaptic target neurons. However, this has been achieved at only a limited number of model synapses, including the squid giant synapse and the mammalian calyx of Held. Cortical presynaptic termina...

We developed a biophysically detailed multiscale model of mouse primary motor cortex (M1) with over 10,000 neurons and 35 million synapses. We focused on intratelencephalic (IT) and pyramidal-tract (PT) neurons of layer 5 (L5), which were modeled at high multicompartment resolution. Wiring densities were based on prior detailed measures from mouse...

Pattern separation is a fundamental brain computation that converts small differences in synaptic input patterns into large differences in action potential (AP) output patterns. Pattern separation plays a key role in the dentate gyrus, enabling the efficient storage and recall of memories in downstream hippocampal CA3 networks. Several mechanisms f...

Biophysical modeling of neuronal networks helps to integrate and interpret rapidly growing and disparate experimental datasets at multiple scales. The NetPyNE tool (www.netpyne.org) provides both programmatic and graphical interfaces to develop data-driven multiscale network models in NEURON. NetPyNE clearly separates model parameters from implemen...

Biophysical modeling of neuronal networks helps to integrate and interpret rapidly growing and disparate experimental datasets at multiple scales. The NetPyNE tool ( www.netpyne.org ) provides both programmatic and graphical interfaces to develop data-driven multiscale network models in NEURON. NetPyNE clearly separates model parameters from implem...

Using an extracellular medium with high potassium/low magnesium concentration with the addition of 4-AP we induced epileptiform activity in combined hippocampus/entorhinal cortex slices of the rat brain [1]. In this in vitro model of temporal lobe epilepsy, we observed the repeating sequences of interictal discharge (IID) regimes and seizure-like e...

New & noteworthy: We developed models of motor cortex corticospinal neurons that replicate in vitro dynamics, including hyperpolarization-induced sag and realistic firing patterns. Models demonstrated resonance in response to synaptic stimulation, with resonance frequency increasing in apical dendrites with increasing distance from soma, matching...

A set of methods is described for channelrhodopsin-2 (ChR2)-based synaptic circuit analysis that combines photostimulation of virally transfected presynaptic neurons’ axons with whole-cell electro-physiological recordings from retrogradely labeled postsynaptic neurons. The approach exploits the preserved photoexcitability of ChR2-expressing axons i...

Presentation on "25th Annual Computational Neuroscience Meeting: CNS-2016 " BMC Neuroscience 17, 112-113 (2016).

ICGenealogy: towards a common topology of neuronal ion channel function and genealogy in model and experiment Ion channels are fundamental constituents determining the function of single neurons and neuronal circuits. To understand their complex interactions, the field of computational modeling has proven essential: since its emergence, thousands...

Auditory cortex (AC) layer 5B (L5B) contains both corticocollicular neurons, a type of pyramidal-tract neuron projecting to the inferior colliculus, and corticocallosal neurons, a type of intratelencephalic neuron projecting to contralateral AC. Although it is known that these neuronal types have distinct roles in auditory processing and different...

AEC practitioners commonly use discipline-specific computer-based information modeling and analysis processes today. However, these practitioners lack simple, flexible, formal frameworks to communicate and integrate these processes and information amongst multiple disciplines. They therefore struggle to quickly and accurately achieve balanced and n...

Custom Matlab routines for length density analysis of neuronal morphology. DOI: http://dx.doi.org/10.7554/eLife.05422.012

The motor cortex (M1) is classically considered an agranular area, lacking a distinct layer 4 (L4). Here, we tested the idea that M1, despite lacking a cytoarchitecturally visible L4, nevertheless possesses its equivalent in the form of excitatory neurons with input-output circuits like those of the L4 neurons in sensory areas. Consistent with this...

Roughly 10% of corticospinal neurons are located in a distinct cluster in secondary somatosensory cortex (S2) (Nudo and Masterton, 1990). Characteristic intrinsic properties of these S2 corticospinal neurons resemble those of corticospinal neurons in primary motor cortex (M1) (Suter et al, 2013). Local circuits in S2 differ in some ways from those...

An enduring enigma about the functional organization of agranular cortical areas such as primary motor cortex (M1; area 4) is the absence of a distinct layer 4 (L4) and how this relates to the local and long-range synaptic circuits. We investigated the possibility that M1 possesses the hodological equivalent of L4 in the form of excitatory neurons...

Neurophotonics methods offer powerful ways to access neuronal signals and circuits. We highlight recent advances and current themes in this area, emphasizing tools for mapping, monitoring, and manipulating excitatory projection neurons and their synaptic circuits in mouse motor cortex.

The deceptively simple laminar structure of neocortex belies the complexity of intra- and interlaminar connectivity. We developed a computational model based primarily on a unified set of brain activity mapping studies of mouse M1. The simulation consisted of 775 spiking neurons of 10 cell types with detailed population-to-population connectivity....

Corticospinal neurons (CSP) exhibit intriguing morphology: they form a prominent apical tuft in layer 1, and their perisomatic dendrites sample about half the thickness of cortex. We first quantified the three-dimensional dendritic arbors of identified corticospinal neurons (CSP) in mouse motor cortex (N=24) and found that dendritic length density...

Coincidence detection of stimuli has been reported for single cells. We evaluated a network model of primary motor cortex (M1) that detects coincidences based on arrival of signals at different network layers, rather than one cell’s afferents. Our model was made up of 775 spiking neurons of 10 cell types (4 excitatory and 6 inhibitory) with details...

Corticospinal neurons occur not only in primary motor cortex (M1) but also in a separate lateral parietal area, Region B (RB), which is largely co-extensive with secondary somatosensory cortex (S2); indeed, ~10% of corticospinal neurons in the cortex are found in S2/RB (Nudo and Masterton, 1990). Whether and how S2/RB is interconnected with M1 is l...

Corticospinal pyramidal neurons project mono-synaptically from the motor cortex to the spinal cord: these upper motor neurons are critical for voluntary movement control, and their deterioration in diseases such as amyotrophic lateral sclerosis is devastating. Corticospinal neurons receive strong excitatory input from the local cortical circuit and...

Pyramidal neurons in neocortical layer 5B can be grouped into two classes based on their axonal projection target. Intratelencephalic (IT) type neurons send axons to ipsi- and contralateral cortical locations as well as to the contralateral striatum, but do not project out of the telencephalon. Pyramidal tract (PT) type neurons do not send axon col...

This article was motivated by the conference entitled "Perception & Action - An Interdisciplinary Approach to Cognitive Systems Theory," which took place September 14-16, 2010 at the Santa Fe Institute, NM, USA. The goal of the conference was to bring together an interdisciplinary group of neuroscientists, roboticists, and theorists to discuss the...

In mouse motor cortex, layer 5B contains pyramidal neurons projecting to various long-range targets, which are important for different aspects of motor control. Neurons projecting to the spinal cord (corticospinal) and to the contralateral striatum (corticostriatal) are found side-by-side, yet display distinct patterns of local excitatory connectiv...

Advanced neurophysiology experiments often integrate multiple types of measurements and demand flexibility in the specification and use of multiple channels for data I/O. There is an increasing need for software to coordinate and automate these measurements, which needs to meet multiple demands: it should provide intuitive graphical user interfaces...

Physiological measurements in neuroscience experiments often involve complex stimulus paradigms and multiple data channels. Ephus (http://www.ephus.org) is an open-source software package designed for general-purpose data acquisition and instrument control. Ephus operates as a collection of modular programs, including an ephys program for standard...

It is widely believed that seizures result from increased hypersynchronous neuronal firing. In a rat model of temporal lobe epilepsy a substantial proportion of dentate gyrus granule cells (DG) and CA3 pyramidal cells (CA3) increase their firing rate minutes before locally recorded electrographic seizure onset. We analyzed unit recording data to te...

AEC projects require multidisciplinary solutions. Today AEC professionals have formal methods to help them manage and communicate much of a single discipline's information; however, they lack formal methodologies to manage and communicate information and processes among multiple disciplines. As a result, AEC projects have difficulty quickly and acc...

Parametric approaches have impacted the work of specific industry sectors. However, AEC projects continue to struggle to integrate the work of many disciplines. The prevalent approach to integration has been to provide engineers with methods to construct a central model, simplifying the need to maintain integrity across multiple information represe...

We discuss an approach in which engineers formally and iteratively construct information representations, called Perspectives, from information in other Perspectives using personal computational assistants, called Perspectors. Engineers can select from predefined, reusable, Perspectors, or program new Perspectors, and compose them into directed acy...

As engineers design, plan, and execute architecture, engineering, and construction (AEC) projects, they construct task-specific views. These views contain information that is structured for their specific tasks. Engineers generally construct these views based on information contained in other engineers' views. Traditionally, engineers have manually...

To perform specific tasks, Architecture, Engineering, and Construction (AEC) professionals construct task-specific engineering views from information in other engineering views. Each view contains project information that is structured for an engineer's specific task; engineers are responsible for the information in their respective views. This pap...

As they design, plan, and execute AEC projects, engineers today construct task-specific geometric views based on information contained in other engineers' geometric views. Traditionally, engineers have constructed these views manually, using pencils and more recently CAD. Manually constructing views is often difficult, time-consuming, and error-pro...

: Architecture, Engineering, and Construction (AEC) projects require multidisciplinary solutions. Today AEC professionals have formal methods to help them manage and communicate much of a single discipline's information; however, they lack formal methodologies to manage and communicate information and processes among multiple disciplines. As a resu...

Sustainable development requires the design-construction delivery process to incorporate new sets of environmental, social, and economic goals; however, AEC projects today have difficulty clearly and collectively defining these goals, and executing an integrated design process that achieves them. We are designing a framework to enable AEC teams to...

We formalize a multidisciplinary project model as a directed acyclic graph of dependencies between representations. For the nodes of this graph, we formalize a generic representation, called a "perspective," which contains "features" that describe the design for a specific task. These features contain data types such as 3D surfaces, lines, and poin...