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Quantitative data are presented on the orientation and direction specificity of the responses of cells in macaque monkey striate cortex. There is a bimodal distribution of direction-specific and nondirection-specific cells, with similar orientation tuning in each class. Cells range in orientation bandwidth at half amplitude from 6 degrees to 360 degrees(More)
The present study examined the interaction between spatial attention and global/local feature processing of visual hierarchical stimuli. Event-related brain potentials (ERPs) were recorded from subjects who detected global or local targets at attended locations while ignoring those at unattended locations. Spatial attention produced enhanced occipital P1(More)
BACKGROUND While human auditory cortex is known to contain tonotopically organized auditory cortical fields (ACFs), little is known about how processing in these fields is modulated by other acoustic features or by attention. METHODOLOGY/PRINCIPAL FINDINGS We used functional magnetic resonance imaging (fMRI) and population-based cortical surface analysis(More)
While auditory cortex in non-human primates has been subdivided into multiple functionally specialized auditory cortical fields (ACFs), the boundaries and functional specialization of human ACFs have not been defined. In the current study, we evaluated whether a widely accepted primate model of auditory cortex could explain regional tuning properties of(More)
We examined the neural mechanisms of functional asymmetry between hemispheres in the processing of global and local information of hierarchical stimuli by measuring hemodynamic responses with functional magnetic resonance imaging (fMRI). In a selective attention task, subjects responded to targets at the global or local level of compound letters that were(More)
Is attentional selection between local and global forms based on spatial frequency? This question was examined by having subjects identify local or global forms of stimuli that had been "contrast balanced," a technique that eliminates low spatial frequencies. Response times (RTs) to global (but not local) forms were slowed for contrast-balanced stimuli,(More)
OBJECTIVE Multichannel compression (MCC) processing can alter the speech spectrum, perhaps reducing spectral contrasts that are important for the discrimination of certain speech sounds. The effect of MCC processing on the discrimination of vowels and voiced stop consonants was studied. DESIGN Vowels and voiced stop consonants were MCC-processed in two(More)
The current study aimed to investigate the effect of attentional selection of distinctive local elements on the processing of hierarchically organized patterns. Event-related brain potentials (ERPs) were recorded from subjects during identifications of global or local shapes of hierarchical patterns where either all local elements were identical(More)
The accurate mapping of functional magnetic resonance imaging (fMRI) activations to anatomical structures is critical for fMRI studies of brain organization. In the commonly used functional space analysis method, functional images are realigned to a functional reference image and processed in low-resolution functional space. The average functional(More)
We analyzed computerized finger tapping metrics in four experiments. Experiment 1 showed tapping-rate differences associated with hand dominance, digits, sex, and fatigue that replicated those seen in a previous, large-scale community sample. Experiment 2 revealed test-retest correlations (r = .91) that exceeded those reported in previous tapping studies.(More)