Search results for "ACOUSTIC"
showing 10 items of 1590 documents
Behavioral and event-related potential distraction effects with regularly occurring auditory deviants
2007
When auditory stimulation contains infrequent task-irrelevant changes (deviants), behavioral responses to task-relevant aspects of the stimulation are prolonged. Event-related brain potentials (ERPs) show that deviants elicit mismatch negativity (MMN), P3a, and reorienting negativity (RON). Here, we examine whether distraction effects can also be elicited within fixed auditory sequences with deviant probabilities of 0.25, 0.33, and 0.5. Deviants varied either in pitch, loudness, or sound source location. In all conditions MMN and P3a were elicited, suggesting that an automatic detection of and an attentional allocation to the change occurred. With relative frequencies of 25% and 33%, devian…
Response repetition vs. response change modulates behavioral and electrophysiological effects of distraction
2004
If stimulation occasionally contains distracting information, behavioral responses to task-relevant aspects of the stimulation are prolonged and more error prone. Additionally, event-related potentials (ERPs) acquired in an auditory distraction paradigm show that the distracting information elicits the components mismatch negativity (MMN), P3a and reorienting negativity (RON). Here, we assess to what extent sequential dependencies in the stimulation influence such indicators of distraction. Data of four experiments were reanalyzed for response repetition and response change trials separately. Behavioral performance on Deviants suggests markedly smaller distraction effects in change compared…
Alterations in visual and auditory processing in hemispatial neglect: An evoked potential follow-up study
2010
Hemispatial neglect is common after cerebrovascular stroke in the right hemisphere. Cortical electrophysiological studies, especially investigations of both visual and auditory processing in subjects with neglect are sparse. Our purpose was to assess whether and to which extent subjects with neglect may show impairments in both visual and auditory processing. Thereby, we assessed the evolution of changes in sensory processing and neglect symptoms over a 6 month follow-up period. Twenty-one stroke subjects with hemispatial neglect were studied at baseline, 3 weeks later and at 6 months follow-up. At enrollment, 12 patients were in Acute/subacute and 9 were in the chronic stage of stroke. Vis…
Sequential analysis of the brain's transfer properties during consecutive REM episodes
1995
Abstract Classical analysis of the spontaneous sleep EEG has revealed alterations of REM sleep in psychiatric diseases and under the influence of drugs. In order to elucidate possible functional differences between different REM episodes even in healthy subjects we investigated in 10 volunteers the transfer properties of the brain by measuring auditory (AEP) and visual evoked potentials (VEP) from scalp positions Fz, Cz and Pz during the night. According to linear system theory we computed the so-called amplitude-frequency characteristics (AFC) from averaged AEPs and VEPs during the first and each of the following 3 REM episodes. These functions describe the relationship between the input a…
The Influence of Lorazepam upon Pre- and Poststimulus EEG during Sleep in Man
1997
Enhancement of beta power in the spontaneous EEG under the influence of benzodiazepine medication is a well known phenomenon under waking conditions as well as during sleep. On the other hand, in certain frequency bands EEG activity following external stimulation is also enhanced. Therefore, the question arises what relationship exists between pre- and poststimulus EEG under the influence of benzodiazepines. Is an augmentation of beta activity during benzodiazepine medication further enhanced when external stimulation is applied? In order to address this question we compared the spectral power of pre- and poststimulus EEG under 2.5 mg lorazepam during sleep with placebo conditions. The hypo…
Does sound stimulation have additive effects on cognitive-behavioral treatment of chronic tinnitus?
2003
Psychological and physiological habituation are major goals in the treatment of patients suffering from chronic tinnitus. This study evaluates whether sound stimulation provided by use of low level white noise generators (NG) enhances the effects of cognitive-behavioral treatment (CBT). 124 outpatients with tinnitus of >6 months received manualized group treatment and were randomly assigned to the NG/no NG conditions. Those with moderate tinnitus-related distress obtained four sessions focusing on education, while severely distressed subjects were treated according to a full 10-session CBT program. Outcome was assessed at post-treatment and at 6- and 18-month follow-up. No additive effects …
Passive exposure to speech sounds modifies change detection brain responses in adults
2019
In early life auditory discrimination ability can be enhanced by passive sound exposure. In contrast, in adulthood passive exposure seems to be insufficient to promote discrimination ability, but this has been tested only with a single short exposure session in humans. We tested whether passive exposure to unfamiliar auditory stimuli can result in enhanced cortical discrimination ability and change detection in adult humans, and whether the possible learning effect generalizes to different stimuli. To address these issues, we exposed adult Finnish participants to Chinese lexical tones passively for 2 h per day on 4 consecutive days. Behavioral responses and the brain's event-related potenti…
Distinctive Representation of Mispredicted and Unpredicted Prediction Errors in Human Electroencephalography
2015
The predictive coding model of perception proposes that neuronal responses are modulated by the amount of sensory input that the internal prediction cannot account for (i.e., prediction error). However, there is little consensus on what constitutes nonpredicted stimuli. Conceptually, whereas mispredicted stimuli may induce both prediction error generated by prediction that is not perceived and prediction error generated by sensory input that is not anticipated, unpredicted stimuli involves no top-down, only bottom-up, propagation of information in the system. Here, we examined the possibility that the processing of mispredicted and unpredicted stimuli are dissociable at the neurophysiologic…
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…
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 …