Browsing by Author "Eagleman, David M."

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Neural Networks of Colored Sequence Synesthesia
    (Society for Neuroscience, 2013) Tomson, Steffie N.; Narayan, Manjari; Allen, Genevera I.; Eagleman, David M.
    Synesthesia is a condition in which normal stimuli can trigger anomalous associations. In this study,weexploit synesthesia to understand how the synesthetic experience can be explained by subtle changes in network properties. Of the many forms of synesthesia, we focus on colored sequence synesthesia, a form in which colors are associated with overlearned sequences, such as numbers and letters (graphemes). Previous studies have characterized synesthesia using resting-state connectivity or stimulus-driven analyses, but it remains unclear how network properties change as synesthetes move from one condition to another. To address this gap, we used functional MRI in humans to identify grapheme-specific brain regions, thereby constructing a functional “synesthetic” network. We then explored functional connectivity of color and grapheme regions during a synesthesia-inducing fMRI paradigm involving rest, auditory grapheme stimulation, and audiovisual grapheme stimulation. Using Markov networks to represent direct relationships between regions, we found that synesthetes had more connections during rest and auditory conditions. We then expanded the network space to include 90 anatomical regions, revealing that synesthetes tightly cluster in visual regions, whereas controls cluster in parietal and frontal regions. Together, these results suggest that synesthetes have increased connectivity between grapheme and color regions, and that synesthetes use visual regions to a greater extent than controls when presented with dynamic grapheme stimulation. These data suggest that synesthesia is better characterized by studying global network dynamics than by individual properties of a single brain region.
  • Thumbnail Image
    Item
    Providing information to a user through somatosensory feedback
    (2017-04-18) Eagleman, David M.; Novich, Scott; Rice University; Baylor College of Medicine; United States Patent and Trademark Office
    A hearing device may provide hearing-to-touch sensory substitution as a therapeutic approach to deafness. Through use of signal processing on received signals, the hearing device may provide better accuracy with the hearing-to-touch sensory substitution by extending beyond the simple filtering of an incoming audio stream as found in previous tactile hearing aids. The signal processing may include low bitrate audio compression algorithms, such as linear predictive coding, mathematical transforms, such as Fourier transforms, and/or wavelet algorithms. The processed signals may activate tactile interface devices that provide touch sensation to a user. For example, the tactile interface devices may be vibrating devices attached to a vest, which is worn by the user. The vest may also provide other types of information to the user.
  • Thumbnail Image
    Item
    Providing information to a user through somatosensory feedback
    (2018-07-10) Eagleman, David M.; Novich, Scott; Rice University; Baylor College of Medicine; United States Patent and Trademark Office
    A hearing device may provide hearing-to-touch sensory substitution as a therapeutic approach to deafness. Through use of signal processing on received signals, the hearing device may provide better accuracy with the hearing-to-touch sensory substitution by extending beyond the simple filtering of an incoming audio stream as found in previous tactile hearing aids. The signal processing may include low bitrate audio compression algorithms, such as linear predictive coding, mathematical transforms, such as Fourier transforms, and/or wavelet algorithms. The processed signals may activate tactile interface devices that provide touch sensation to a user. For example, the tactile interface devices may be vibrating devices attached to a vest, which is worn by the user. The vest may also provide other types of information to the user.