Sublexical cues affect degraded speech processing: insights from fMRI.

In natural listening situations, speech perception is often impaired by degraded speech sounds arriving at the ear. Contextual speech information can improve the perception of degraded speech and modify neuronal responses elicited by degraded speech. However, most studies on context effects on neural responses to degraded speech confounded lexico-semantic and sublexical cues.

Electrocorticography reveals continuous auditory and visual speech tracking in temporal and occipital cortex.

During natural speech perception, humans must parse temporally continuous auditory and visual speech signals into sequences of words. However, most studies of speech perception present only single words or syllables. We used electrocorticography (subdural electrodes implanted on the brains of epileptic patients) to investigate the neural mechanisms for processing continuous audiovisual speech signals consisting of individual sentences.

Human centromedian-parafascicular complex signals sensory cues for goal-oriented behavior selection.

Experimental research has shown that the centromedian-parafascicular complex (CM-Pf) of the intralaminar thalamus is activated in attentional orienting and processing of behaviorally relevant stimuli. These observations resulted in the hypothesis that the CM-Pf plays a pivotal role in goal-oriented behavior selection. We here set out to test this hypothesis with electrophysiological recordings from patients with electrodes implanted in CM-Pf for deep brain stimulation (DBS) treatment of chronic neuropathic pain.

A Double Dissociation between Anterior and Posterior Superior Temporal Gyrus for Processing Audiovisual Speech Demonstrated by Electrocorticography.

Human speech can be comprehended using only auditory information from the talker's voice. However, comprehension is improved if the talker's face is visible, especially if the auditory information is degraded as occurs in noisy environments or with hearing loss. We explored the neural substrates of audiovisual speech perception using electrocorticography, direct recording of neural activity using electrodes implanted on the cortical surface.

Electrocorticography Reveals Enhanced Visual Cortex Responses to Visual Speech.

Human speech contains both auditory and visual components, processed by their respective sensory cortices. We test a simple model in which task-relevant speech information is enhanced during cortical processing. Visual speech is most important when the auditory component is uninformative.

Altered intrinsic neuronal interactions in the visual cortex of the blind.

In congenital blindness, the brain develops under severe sensory deprivation and undergoes remarkable plastic changes in both structure and function. Visually deprived occipital cortical regions are histologically and morphologically altered and exhibit a strikingly remodeled functional state: absolute levels of neural activity are heightened and are modulated by nonvisual sensory stimulation as well as higher cognitive processes. However, the neuronal mechanisms that underlie this altered functional state remain largely unknown.

Noise alters beta-band activity in superior temporal cortex during audiovisual speech processing.

Speech recognition is improved when complementary visual information is available, especially under noisy acoustic conditions. Functional neuroimaging studies have suggested that the superior temporal sulcus (STS) plays an important role for this improvement. The spectrotemporal dynamics underlying audiovisual speech processing in the STS, and how these dynamics are affected by auditory noise, are not well understood.

Functionally specific oscillatory activity correlates between visual and auditory cortex in the blind.

Many studies have shown that the visual cortex of blind humans is activated in non-visual tasks. However, the electrophysiological signals underlying this cross-modal plasticity are largely unknown. Here, we characterize the neuronal population activity in the visual and auditory cortex of congenitally blind humans and sighted controls in a complex cognitive task.

Levels of error processing in Huntington's disease: a combined study using event-related potentials and voxel-based morphometry.

Huntington's Disease (HD) is a neurogenetic disorder accompanied by an atrophy of the striatum and hence of the dopaminergic (DA) system. Neural processes subserving error processing presumably depend on the DA system. We assessed error processing in manifest HD and in presymptomatic HD-gene-mutation-carriers (pHD) with event-related potentials reflecting error processing (the error negativity or error-related negativity and the error positivity derived from a flanker-task.

Effects of the cannabinoid CB1 receptor antagonist rimonabant on distinct measures of impulsive behavior in rats.

Rationale: Pathological impulsivity is a prominent feature in several psychiatric disorders, but detailed understanding of the specific neuronal processes underlying impulsive behavior is as yet lacking.

Objectives: As recent findings have suggested involvement of the brain cannabinoid system in impulsivity, the present study aimed at further elucidating the role of cannabinoid CB(1) receptor activation in distinct measures of impulsive behavior.

Materials And Methods: The effects of the selective cannabinoid CB(1) receptor antagonist, rimonabant (SR141716A) and agonist WIN55,212-2 were tested in various measures of impulsive behavior, namely, inhibitory control in a five-choice serial reaction time task (5-CSRTT), impulsive choice in a delayed reward paradigm, and response inhibition in a stop-signal paradigm.