Listening Difficulties in Children: Behavior and Brain Activation Produced by Dichotic Listening of CV Syllables

M187. A MULTIMODAL, NEUROIMAGING STUDY OF TDCS MECHANISMS RELATED TO AUDITORY VERBAL HALLUCINATIONS IN HEALTHY INDIVIDUALS

Schizophrenia Bulletin ◽

10.1093/schbul/sbaa030.499 ◽

2020 ◽

Vol 46 (Supplement_1) ◽

pp. S207-S207

Author(s):

Marquardt Lynn ◽

Isabella Kusztrits ◽

Alexander R Craven ◽

Kenneth Hugdahl ◽

Karsten Specht ◽

...

Keyword(s):

Electric Field ◽

Mr Spectroscopy ◽

Dichotic Listening ◽

Block Design ◽

Brain Activation ◽

Healthy Individuals ◽

Auditory Verbal Hallucinations ◽

Sham Stimulation ◽

Dichotic Listening Task ◽

Listening Task

Abstract Background Transcranial direct current stimulation (tDCS) is a brain stimulation method which is growing in popularity in both research and clinical settings, especially as a treatment of auditory verbal hallucinations (AVH) in patients with schizophrenia. However, the underlying neural mechanisms of this tDCS treatment are poorly understood. Current AVH models propose that AVH arise from hyperactivation in the left temporo parietal (LTPC), causing AVH, and from hypoactivation in the left dorsolateral prefrontal cortex (LDLPFC), leading to diminished control over AVH. We aimed to “mimic” this hyper-/hypoactivation pattern in healthy individuals with tDCS by placing the excitatory anode above the LTPC and the inhibitory cathode over the LDLPFC and then to study the effects of tDCS on these brain areas. Previous studies examined either brain activation, neurochemistry, or behavior, with other electrode montages, but few looked at those aspects together. The present study therefore examined tDCS effects with fMRI (functional magnetic resonance imaging), MR spectroscopy, behavioral tasks and simulation of the electric field in a multimodal approach. We hypothesized that tDCS would (a) lead to similar behavioral deficits in healthy individuals as in schizophrenia patients and (b) induce changes in the stimulated areas on neurotransmitter and functional activation level. Methods Thirty-two healthy participants (18 males, mean age=26 yrs) were tested twice, ca. one week apart, with either real or sham (control) 2mA tDCS for 20 min while in a GE 750, 3T MRI scanner. The order of real/sham stimulation was counterbalanced in a double-blind design. During fMRI, participants completed a dichotic listening task in a block design, in order to measure behavior and brain activation changes. Before and after fMRI/tDCS, MR spectroscopy was carried out in two voxels placed under the electrodes. The data was analyzed with repeated measures ANOVAs. After data-collection, the structural T1 sequence was used to simulate the electric field of tDCS stimulation. Results Glx (Glutamate and glutamine combined) showed a trend (F(1,31)=3.35, p=.077, η2p=.098) to increase after tDCS stimulation compared to before, however this was not electrode specific. Neither fMRI, nor the dichotic listening task (all F≤1.64, p≥.203, η2p≤.052) showed any stimulation specific differences between real and sham stimulation. The tDCS simulation revealed large individual differences in the electric field induced. Discussion In the present study, tDCS seemed to have little effect on the measured brain parameters and little validation for the AVH model was found. The mechanisms of tDCS and how it affects the underlying brain tissue are poorly understood and seem to be affected by different stimulation parameters like stimulation duration, current strength and electrode montage. To use tDCS most effectively in schizophrenia research and treatment of auditory hallucinations, it should be validated with a multitude of methods, similar to the approach described here.

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Listening difficulties in children: Behavior and brain activation produced by dichotic listening of CV syllables

10.1101/721209 ◽

2019 ◽

Cited By ~ 1

Author(s):

David R. Moore ◽

Kenneth Hugdahl ◽

Hannah J. Stewart ◽

Jennifer Vannest ◽

Audrey J. Perdew ◽

...

Keyword(s):

Auditory Processing ◽

Dichotic Listening ◽

Memory Load ◽

Brain Activity ◽

Inferior Frontal Gyrus ◽

Brain Activation ◽

Activity Level ◽

Laterality Index ◽

The Right ◽

Interaural Level Differences

AbstractListening difficulties (LiD), also known as auditory processing disorders, are common in children with and without hearing loss. Impaired interactions between the two ears have been proposed as an important component of LiD. Previous studies have focused on testing using multiple sequential dichotic digits that carry a substantial memory load and executive control demands. We examined the ability of 6-13 year old children with normal audiometric thresholds to identify and selectively attend to dichotically presented CV syllables using the Bergen Dichotic Listening Test (BDLT;www.dichoticlistening.com). Children were recruited as typically developing (TD; n=39) or having LiD (n=35) based primarily on composite score of the ECLiPS caregiver report. Different single syllables (ba, da, ga, pa, ta, ka) were presented simultaneously to each ear (6×36 trials). Children reported the syllable heard most clearly (non-forced, NF) or the syllable presented to the right (forced, FR) or left (FL) ear. Interaural level differences (ILDs) manipulated bottom-up perceptual salience. Dichotic listening data (correct responses, Laterality Index) were analyzed initially by group (LiD, TD), age, report method (NF, FR, FL) and ILD (0, ± 15 dB) and compared with speech-in-noise thresholds (LiSN-S) and cognitive performance (NIH Toolbox). fMRI measured brain activation produced by a receptive speech task that segregated speech, phonetic and intelligibility components. Some activated areas (planum temporale, inferior frontal gyrus and orbitofrontal cortex) were correlated with dichotic results in TD children only.Neither group, age nor report method affected the Laterality Index of right/left recall. However, a significant interaction was found between ear, group and ILD. Children with LiD were more influenced by large ILDs, especially favoring the left ear, than were TD children. Neural activity associated with Speech, Phonetic and Intelligibility sentence cues did not significantly differ between groups. Significant correlations between brain activity level and BDLT were found in several frontal and temporal locations for the TD but not for the LiD group.Children with LiD were more influenced by large ILDs, especially favoring the left ear, than were TD children and were thus less able to modulate performance through attention, and more driven by the physical properties of the acoustic stimuli.

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Interhemispheric transfer evaluation in multiple sclerosis 1The authors would like to thank Claude-Alain Hauert and Christoph Michel for their assistance in the evaluation of motor tapping and Michel Habib for his suggestions and comments. This work was supported by a grant from the Swiss Society of Multiple Sclerosis.

Swiss Journal of Psychology ◽

10.1024//1421-0185.59.3.150 ◽

2000 ◽

Vol 59 (3) ◽

pp. 150-158 ◽

Cited By ~ 2

Author(s):

Nadia Ortiz ◽

Michael Reicherts ◽

Alan J. Pegna ◽

Encarni Garran ◽

Michel Chofflon ◽

...

Keyword(s):

Multiple Sclerosis ◽

Corpus Callosum ◽

Lexical Decision ◽

Dichotic Listening ◽

Neurological Impairment ◽

Interhemispheric Transfer ◽

Decision Task ◽

Swiss Society ◽

Listening Test ◽

Relapsing Remitting

Patients suffering from Multiple Sclerosis (MS) have frequently been found to suffer from damage to callosal fibers. Investigations have shown that this damage is associated with signs of hemisphere disconnections. The aim of our study was to provide evidence for the first signs of interhemispheric dysfunction in a mildly disabled MS population. Therefore, we explored whether the Interhemispheric Transfer (IT) deficit is multi-modal and sought to differentiate two MS evolution forms, on the basis of an interhemispheric disconnection index. Twenty-two patients with relapsing-remitting form of MS (RRMS) and 14 chronic-progressive (CPMS) were compared with matched controls on four tasks: a tachistoscopic verbal and non-verbal decision task, a dichotic listening test, cross tactile finger localization and motor tapping. No overall impairment was seen. The dichotic listening and lexical decision tasks were the most sensitive to MS. In addition, CPMS patients' IT was more impaired and was related to the severity of neurological impairment. The different sizes of the callosal fibers, which determine their vulnerability, may explain the heterogeneity of transfer through the Corpus Callosum. Therefore, evaluation of IT may be of value as an index of evolution in MS.

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