Understanding how humans code for and respond to environmental uncertainty/regularity is a question shared by current computational and neurobiological approaches to human cognition. To date, studies investigating neurobiological systems that track input uncertainty have examined responses to uni-sensory streams. It is not known, however, whether there exist brain systems that combine information about the regularity of input streams presented to different senses.
View Article and Find Full Text PDFPeople seek novelty in everyday life, but they also enjoy viewing the same movies or reading the same novels a second time. What changes and what stays the same when re-experiencing a narrative? In examining this question with functional neuroimaging, we found that brain activity reorganizes in a hybrid, scale-dependent manner when individuals processed the same audiovisual narrative a second time. At the most local level, sensory systems (occipital and temporal cortices) maintained a similar temporal activation profile during the two viewings.
View Article and Find Full Text PDFBlindness is a unique model for understanding the role of experience in the development of the brain's functional and anatomical architecture. Documenting changes in the structure of anatomical networks for this population would substantiate the notion that the brain's core network-level organization may undergo neuroplasticity as a result of life-long experience. To examine this issue, we compared whole-brain networks of regional cortical-thickness covariance in early blind and matched sighted individuals.
View Article and Find Full Text PDFNeurosci Biobehav Rev
October 2015
Gestures play an important role in face-to-face communication and have been increasingly studied via functional magnetic resonance imaging. Although a large amount of data has been provided to describe the neural substrates of gesture comprehension, these findings have never been quantitatively summarized and the conclusion is still unclear. This activation likelihood estimation meta-analysis investigated the brain networks underpinning gesture comprehension while considering the impact of gesture type (co-speech gestures vs.
View Article and Find Full Text PDFIt is known that features of stimuli in the environment affect the strength of functional connectivity in the human brain. However, investigations to date have not converged in determining whether these also impact functional networks' global features, such as modularity strength, number of modules, partition structure, or degree distributions. We hypothesized that one environmental attribute that may strongly impact global features is the temporal regularity of the environment, as prior work indicates that differences in regularity impact regions involved in sensory, attentional and memory processes.
View Article and Find Full Text PDFWith a focus on receptive language, we examine the neurobiological evidence for the interdependence of receptive and expressive language processes. While we agree that there is compelling evidence for such interdependence, we suggest that Pickering & Garrod's (P&G's) account would be enhanced by considering more-specific situations in which their model does, and does not, apply.
View Article and Find Full Text PDFA hand grasping a cup or gesturing "thumbs-up", while both manual actions, have different purposes and effects. Grasping directly affects the cup, whereas gesturing "thumbs-up" has an effect through an implied verbal (symbolic) meaning. Because grasping and emblematic gestures ("emblems") are both goal-oriented hand actions, we pursued the hypothesis that observing each should evoke similar activity in neural regions implicated in processing goal-oriented hand actions.
View Article and Find Full Text PDFWhen people talk to each other, they often make arm and hand movements that accompany what they say. These manual movements, called "co-speech gestures," can convey meaning by way of their interaction with the oral message. Another class of manual gestures, called "emblematic gestures" or "emblems," also conveys meaning, but in contrast to co-speech gestures, they can do so directly and independent of speech.
View Article and Find Full Text PDFWe present a computational framework suitable for a data-driven approach to structural equation modeling (SEM) and describe several workflows for modeling functional magnetic resonance imaging (fMRI) data within this framework. The Computational Neuroscience Applications Research Infrastructure (CNARI) employs a high-level scripting language called Swift, which is capable of spawning hundreds of thousands of simultaneous R processes (R Development Core Team, 2008), consisting of self-contained SEMs, on a high performance computing system (HPC). These self-contained R processing jobs are data objects generated by OpenMx, a plug-in for R, which can generate a single model object containing the matrices and algebraic information necessary to estimate parameters of the model.
View Article and Find Full Text PDFFunctional magnetic resonance imaging (fMRI) has led to an enormous growth in the study of cognitive neuroanatomy, and combined with advances in high-field electrophysiology (and other methods), has led to a fast-growing field of human neuroscience. Technological advances in both hardware and software will lead to an ever more promising future for fMRI. We have developed a new computational framework that facilitates fMRI experimentation and analysis, and which has led to some rethinking of the nature of experimental design and analysis.
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