Person:
Markowitz, Jeffrey

Profile Picture

Email Address

AA Acceptance Date

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

Markowitz

First Name

Jeffrey

Name

Markowitz, Jeffrey
Author's Publications: search.filters.isAuthorOfPublication.17aeeb9d-b210-4714-9f7c-90de88e201ba

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Publication
    A fast and accurate zebra finch syllable detector
    (Public Library of Science, 2017) Pearre, Ben; Perkins, L. Nathan; Markowitz, Jeffrey; Gardner, Timothy J.
    The song of the adult male zebra finch is strikingly stereotyped. Efforts to understand motor output, pattern generation, and learning have taken advantage of this consistency by investigating the bird’s ability to modify specific parts of song under external cues, and by examining timing relationships between neural activity and vocal output. Such experiments require that precise moments during song be identified in real time as the bird sings. Various syllable-detection methods exist, but many require special hardware, software, and know-how, and details on their implementation and performance are scarce. We present an accurate, versatile, and fast syllable detector that can control hardware at precisely timed moments during zebra finch song. Many moments during song can be isolated and detected with false negative and false positive rates well under 1% and 0.005% respectively. The detector can run on a stock Mac Mini with triggering delay of less than a millisecond and a jitter of σ ≈ 2 milliseconds.
  • Thumbnail Image
    Publication
    Dynamic illumination of spatially restricted or large brain volumes via a single tapered optical fiber
    (2017) Pisanello, Ferruccio; Mandelbaum, Gil; Pisanello, Marco; Oldenburg, Ian A.; Sileo, Leonardo; Markowitz, Jeffrey; Peterson, Ralph; Della Patria, Andrea; Haynes, Trevor; Emara, Mohamed S.; Spagnolo, Barbara; Datta, Sandeep; De Vittorio, Massimo; Sabatini, Bernardo
    Optogenetics promises spatiotemporal precise control of neural processes using light. However, the spatial extent of illumination within the brain is difficult to control and cannot be adjusted using standard fiber optics. We demonstrate that optical fibers with tapered tips can be used to illuminate either spatially restricted or large brain volumes. Remotely adjusting the light input angle to the fiber varies the light-emitting portion of the taper over several millimeters without movement of the implant. We use this mode to activate dorsal versus ventral striatum of individual mice and reveal different effects of each manipulation on motor behavior. Conversely, injecting light over the full numerical aperture of the fiber results in light emission from the entire taper surface, achieving broader and more efficient optogenetic activation of neurons when compared to the standard flat-faced fiber stimulation. Thus, tapered fibers permit focal or broad illumination that can be precisely and dynamically matched to experimental needs.