Jennifer L. Collinger, Ph.D. - US grants

ABSTRACT Humans interact with their environment in countless ways and can switch seamlessly between activities. Even for seemingly simple tasks, a variety of sensory inputs are integrated to create a motor plan to complete a task. Take the example of picking up a glass. Visual, tactile, and proprioceptive inputs provide cues about the position and weight of the object as well as limb state. Additional sensory and contextual inputs can also influence the movement. For example, a person might pick up a glass differently if she is intending to take a drink, versus clear off a table. She may grasp a glass more carefully if it is very full to avoid spilling it requiring a change in the motor control scheme. Our central hypothesis is that sensory and motor aspects of task context systematically modulate the neural representation of action as well as conscious sensory perception. We will manipulate aspects of task context to study sensorimotor processing during grasping and object exploration tasks. Intracortical recordings from human motor cortex will be used to study the neural representation of action for various manipulations of task goals, motor control schemes, and expected and actual sensory inputs. Sensory input will be provided using both intact perception (vision) and intracortical microstimulation of somatosensory cortex to impart cutaneous sensations. Tasks involving object grasping and exploration will be performed with a brain-computer interface (BCI) and robotic arm and hand, which allows us to precisely control the mapping between neural activity and movement as well as the somatosensory inputs. Previous work supports the idea that neural activity generated during attempted movements in people with spinal cord injury exhibits the same relationship to movement variables as an able-bodied subject. Similarly, stimulation of somatosensory cortex in a person with chronic tetraplegia generates localized sensations that follow the expected spatial organization. Population-level analysis will be applied to the neuronal recordings to reveal patterns of neural activity generated by each facet of context to gain a better understanding of how goals, motor control schemes, and expected and actual sensory inputs influence the neural representation of action. We will study how vision and tactile sensation are integrated to drive conscious perception during object exploration. Conscious perception will be documented via verbal report as well as psychophysical experiments. This project will address basic- science questions about the influence of context on sensorimotor processing. The findings of this study could broadly impact neurorehabilitation approaches, while also improving the generalizability and performance of BCIs for restoring upper limb function.

Brain-computer interfaces (BCIs) have the potential to revolutionize communication and mobility for people with a variety of neurological conditions and injuries. Successful translation of BCIs to actual clinical use by such people depends on close and productive multidisciplinary interactions, and requires recognition of and attention to a set of crucial issues. The International BCI Meeting Series (1999, 2002, 2005, 2010, 2013, 2016, and 2018) convened a wide range of research groups and disciplines vital to BCI research and triggered many productive interactions and collaborations. Significant progress has been made towards restoring communication and mobility, so the 2020 International BCI Meeting will focus on emerging applications and techniques with the theme ?BCIs: The Next Frontier?. The meeting will be organized under the leadership of a Program Committee appointed by the BCI Society. The meeting will encourage and facilitate the development and translation of BCIs into clinically- viable devices through the following specific aims: 1) Convene and foster productive interactions among all the disciplines and constituencies whose cooperation is crucial to successful BCI research and development. No other venue brings them all together. 2) Present a concise and comprehensive update of the current state of BCI research and development. 3) Address in focused workshops the major topics critical for continued progress in BCI research and development. Additional topics of broad interest will be chosen based on workshop proposals and abstracts submitted by participants. 4) Promote the education and development of new researchers through the participation of many graduate students and postdoctoral fellows. Networking events will encourage interactions between new and established researchers and particularly target underrepresented groups of researchers. 5) Maximize the immediate and long-term Meeting impact through publication by the journal Brain Computer Interfaces of a special issue of peer-reviewed primary articles and focused reviews derived from the meeting. In summary, this meeting will assemble scientists, engineers, clinicians and policymakers involved in BCI research and clinical use, review the present state of the field, address key issues critical to further progress, and promote the education and participation of young researchers. This meeting and the resulting comprehensive publications will, like its predecessors, contribute greatly to BCI research and development.

ABSTRACT Humans can skillfully control their grasp during actions as complex and dynamic as swinging a tennis racket, and as simple and static as holding a briefcase. Both tasks require the use of sensory feedback to achieve and maintain an appropriate grasp force. There is evidence that motor and somatosensory cortices communicate task-relevant information in order to enable skillful movement. Our primary goal is to uncover the motor cortical dynamics underlying grasp force control and determine the extent to which these dynamics are mediated by behavioral context and corticocortical communication of somatosensory feedback. We propose to study the cortical control of grasp by leveraging the unique experimental paradigms afforded by a bidirectional human brain-computer interface study in which participants with tetraplegia have intracortical electrode arrays implanted in motor and somatosensory cortex. Previous work, primarily focused on reaching movements, has demonstrated that motor cortex exhibits population dynamics that are constrained within low- dimensional manifold. We have identified similar dynamic responses within human motor cortex that contain information about grasp force. However, these responses are task-dependent and can change as the complexity of the proximal arm movement changes. Here we will extend that work to study the context- dependence of M1 dynamics across a range of static and dynamic hand and arm movements including both overt and covert (i.e., imagined) behaviors. Sophisticated motor control relies on sensory information to shape neural control signals emanating from motor cortex, yet very little is known about the flow of information from somatosensory to motor cortex for the control of the hand. We aim to quantify the corticocortical communication pathways across a range of task contexts through the analysis of simultaneous neural recordings in motor and somatosensory cortex. We will then use intracortical microstimulation to probe these communication pathways while providing task-relevant sensory feedback as well as task-irrelevant stimulation as a control. Finally, we will use a brain-computer interface to test whether there is the potential for plasticity within the corticocortical communication circuits, or whether communication is constrained by between-area dynamics. Successful completion of this proposal will lead to new knowledge about the role of M1 in dynamic and static grasp behaviors. We will quantify how somatosensory input is communicated with M1 and whether corticocortical communication pathways can be modified through training, which has relevance to understanding skill learning and improving rehabilitation.