Search results for "ECoG"
showing 10 items of 3774 documents
Modulating memory performance in healthy subjects with Trancranial Direct Current Stimulation over the right dorsolateral prefrontal cortex
2015
Objective: The role of the Dorsolateral Prefrontal Cortex (DLPFC) in recognition memory has been well documented in lesion, neuroimaging and repetitive Transcranial Magnetic Stimulation (rTMS) studies. The aim of the present study was to investigate the effects of transcranial Direct Current Stimulation (tDCS) over the left and the right DLPFC during the delay interval of a non-verbal recognition memory task. Method: 36 right-handed young healthy subjects participated in the study. The experimental task was an Italian version of Recognition Memory Test for unknown faces. Study included two experiments: in a first experiment, each subject underwent one session of sham tDCS and one session of…
Recognition memory and prefrontal cortex: Dissociating recollection and familiarity processes using rTMS
2008
Recognition memory can be supported by both the assessment of the familiarity of an item and by the recollection of the context in which an item was encountered. The neural substrates of these memory processes are controversial. To address these issues we applied repetitive transcranial magnetic stimulation (rTMS) over the right and left dorsolateral prefrontal cortex (DLPFC) of healthy subjects performing a remember/know task. rTMS disrupted familiarity judgments when applied before encoding of stimuli over both right and left DLPFC. rTMS disrupted recollection when applied before encoding of stimuli over the right DLPFC. These findings suggest that the DLPFC plays a critical role in recog…
High frequency repetitive transcranial magnetic stimulation (rTMS) reduces EEG-hypofrontality in patients with schizophrenia.
2015
The reduced metabolic activity in the prefrontal brain lobes, so-called hypofrontality, is associated with increased electrophysiological delta-band activity. Schizophrenia inpatients (N=35) received sham-controlled 10Hz rTMS over the left dorsolateral prefrontal cortex in a randomised design. After treatment, the resting electroencephalography revealed a significant decrease in the delta-band activity, which originated in the right prefrontal cortex and correlated with improvements in facial affect recognition.
Decoding Musical Training from Dynamic Processing of Musical Features in the Brain
2018
AbstractPattern recognition on neural activations from naturalistic music listening has been successful at predicting neural responses of listeners from musical features, and vice versa. Inter-subject differences in the decoding accuracies have arisen partly from musical training that has widely recognized structural and functional effects on the brain. We propose and evaluate a decoding approach aimed at predicting the musicianship class of an individual listener from dynamic neural processing of musical features. Whole brain functional magnetic resonance imaging (fMRI) data was acquired from musicians and nonmusicians during listening of three musical pieces from different genres. Six mus…
Synergy of spatial frequency and orientation bandwidth in texture segregation
2021
Defining target textures by increased bandwidths in spatial frequency and orientation, we observed strong cue combination effects in a combined texture figure detection and discrimination task. Performance for double-cue targets was better than predicted by independent processing of either cue and even better than predicted from linear cue integration. Application of a texture-processing model revealed that the oversummative cue combination effect is captured by calculating a low-level summary statistic (\(\Delta CE_m\)), which describes the differential contrast energy to target and reference textures, from multiple scales and orientations, and integrating this statistic across channels wi…
Repetition suppression versus enhancement — it's quantity that matters
2013
Upon repetition, certain stimuli induce reduced neural responses (i.e., repetition suppression), whereas others evoke stronger signals (i.e., repetition enhancement). It has been hypothesized that stimulus properties (e.g., visibility) determine the direction of the repetition effect. Here, we show that the very same stimuli can induce both repetition suppression and enhancement, whereby the only determining factor is the number of repetitions. Repeating the same, initially novel low-visible pictures of scenes for up to 5 times enhanced the blood oxygen level-dependent (BOLD) response in scene-selective areas, that is, the parahippocampal place area (PPA) and the transverse occipital sulcus…
Key issues in decomposing fMRI during naturalistic and continuous music experience with independent component analysis
2014
Background: Independent component analysis (ICA) has been often used to decompose fMRI data mostly for the resting-state, block and event-related designs due to its outstanding advantage. For fMRI data during free-listening experiences, only a few exploratory studies applied ICA.New method: For processing the fMRI data elicited by 512-s modern tango, a FFT based band-pass filter was used to further pre-process the fMRI data to remove sources of no interest and noise. Then, a fast model order selection method was applied to estimate the number of sources. Next, both individual ICA and group ICA were performed. Subsequently, ICA components whose temporal courses were significantly correlated …
Mentalizing eye contact with a face on a video : Gaze direction does not influence autonomic arousal
2018
Recent research has revealed enhanced autonomic and subjective responses to eye contact only when perceiving another live person. However, these enhanced responses to eye contact are abolished if the viewer believes that the other person is not able to look back at the viewer. We purported to investigate whether this "genuine" eye contact effect can be reproduced with pre-recorded videos of stimulus persons. Autonomic responses, gaze behavior, and subjective self-assessments were measured while participants viewed pre-recorded video persons with direct or averted gaze, imagined that the video person was real, and mentalized that the person could see them or not. Pre-recorded videos did not …
Diagnosis and Classification of 17 Diseases from 1404 Subjects via Pattern Analysis of Exhaled Molecules.
2016
We report on an artificially intelligent nanoarray based on molecularly modified gold nanoparticles and a random network of single-walled carbon nanotubes for noninvasive diagnosis and classification of a number of diseases from exhaled breath. The performance of this artificially intelligent nanoarray was clinically assessed on breath samples collected from 1404 subjects having one of 17 different disease conditions included in the study or having no evidence of any disease (healthy controls). Blind experiments showed that 86% accuracy could be achieved with the artificially intelligent nanoarray, allowing both detection and discrimination between the different disease conditions examined.…
Recognition of Root Canal Orifices in Video Sequences as a Future Support System During Endodontic Treatment
2009
Abstract Introduction The objective of this study was to show the practical application of computer-aided techniques for detecting root canal orifices through the access cavity using a video camera mounted on a microscope. Methods A minimum distance classification image recognition algorithm was tested in an in vitro study to assess the possibilities of computer-aided recognition of root canal orifices. A Motic DM143 digital stereo microscope (Motic Germany GmbH, Wetzlar, Germany) was used because it includes a video camera that can be connected via USB1.1 to any computer. Results The newly developed software is capable of communicating with a video camera and can automatically detect the r…