Search results for "mismatch"
showing 10 items of 345 documents
Could audiovisual training be used to improve cognition in extremely low birth weight children?
2011
Aim: To study whether a dyslexia remediation programme, Audilex, improves cognition in extremely low birth (ELBW) children. Methods: Six-year-old ELBW children were allocated to a 5-week training with Audilex or playing control computer games. Before and after intervention, auditory event-related brain potentials (ERP) to sound changes were recorded and reading related skills assessed. Primary outcome was the mismatch negativity (MMN) component of ERP. Secondary outcomes were Audilex Test (ability to perform the Audilex games), the reading skills after the intervention and 2 years later. Of eligible children, 39 (54%) consented and 22 (30%) completed the protocol. Results: The MMN responses…
Long-term physical activity modifies automatic visual processing
2017
Electrophysiologically registered visual mismatch negativity (vMMN) is known to represent automatic visual processing in human visual cortex. Since physical activity (PA) is generally beneficial to cerebrovascular function, we wanted to find out if automatic visual processing is affected by PA. We investigated the connection between long-term leisure-time PA and precognitive visual processing in 32 healthy young males. Participants were divided into active (n = 16) and inactive (n = 16) group according to their leisure-time PA records from the past three years. vMMN was recorded with electroencephalogram using passive oddball paradigm with visual bars. Standard (90%) and deviant (10%) stimu…
Mapping symbols to sounds: electrophysiological correlates of the impaired reading process in dyslexia
2012
Dyslexic and control first-grade school children were compared in a Symbol-to-Sound matching test based on a non-linguistic audiovisual training which is known to have a remediating effect on dyslexia. Visual symbol patterns had to be matched with predicted sound patterns. Sounds incongruent with the corresponding visual symbol (thus not matching the prediction) elicited the N2b and P3a event-related potential (ERP) components relative to congruent sounds in control children. Their ERPs resembled the ERP effects previously reported for healthy adults with this paradigm. In dyslexic children, N2b onset latency was delayed and its amplitude significantly reduced over left hemisphere whereas P…
Visual mismatch negativity for changes in orientation - a sensory memory-dependent response
2008
It remains unclear whether the mismatch negativity of event-related potentials (ERPs) in vision resembles its auditory counterpart in terms of memory relatedness. We recorded ERPs to visual bars in adult humans engaged in an auditory task. In one condition, a bar ('standard') repeated at 400- or 1100-ms non-stimulated intervals was rarely (P = 0.1) replaced by another bar of a different orientation ('deviant'). In the other condition (400-ms intervals), the occurrences of the standards were replaced by 10 (P = 0.1 each) bars of different orientations, including that of the deviant ('control-deviant'). Deviants shifted ERPs towards negative polarity relative to standards in occipital electro…
Importance of the left auditory areas in chord discrimination in music experts as demonstrated by MEG
2011
The brain basis behind musical competence in its various forms is not yet known. To determine the pattern of hemispheric lateralization during sound-change discrimination, we recorded the magnetic counterpart of the electrical mismatch negativity (MMNm) responses in professional musicians, musical participants (with high scores in the musicality tests but without professional training in music) and non-musicians. While watching a silenced video, they were presented with short sounds with frequency and duration deviants and C major chords with C minor chords as deviants. MMNm to chord deviants was stronger in both musicians and musical participants than in non-musicians, particularly in thei…
Neural Responses to Musical Rhythm in Chinese Children With Reading Difficulties
2020
The perception of the musical rhythm has been suggested as one of the predicting factors for reading abilities. Several studies have demonstrated that children with reading difficulties (RD) show reduced neural sensitivity in musical rhythm perception. Despite this prior evidence, the association between music and reading in Chinese is still controversial. In the present study, we sought to answer the question of whether the musical rhythm perception of Chinese children with RD is intact or not, providing further clues on how reading and music might be interlinked across languages. Oddball paradigm was adapted for testing the difference of musical rhythm perception, including predictable an…
Combined Behavioral and Mismatch Negativity Evidence for the Effects of Long-Lasting High-Definition tDCS in Disorders of Consciousness: A Pilot Study
2020
Objective: To evaluate the effects of long-term High-definition transcranial direct current stimulation (HD-tDCS) over precuneus on the level of consciousness (LOC) and the relationship between Mismatch negativity (MMN) and the LOC over the therapy period in patients with Disorders of consciousness (DOCs). Methods: We employed a with-in group repeated measures design with an anode HD-tDCS protocol (2 mA, 20 min, the precuneus) on 11 (2 vegetative state and nine minimally conscious state) patients with DOCs. MMN and Coma Recovery Scale-Revised (CRS-R) scores were measured at four time points: before the treatment of HD-tDCS (T0), after a single session of HD-tDCS (T1), after the treatment of…
Event-related potentials to unattended changes in facial expressions: detection of regularity violations or encoding of emotions?
2013
Visual mismatch negativity (vMMN), a component in event-related potentials (ERPs), can be elicited when rarely presented “deviant” facial expressions violate regularity formed by repeated “standard” faces. vMMN is observed as differential ERPs elicited between the deviant and standard faces. It is not clear, however, whether differential ERPs to rare emotional faces interspersed with repeated neutral ones reflect true vMMN (i.e., detection of regularity violation) or merely encoding of the emotional content in the faces. Furthermore, a face-sensitive N170 response, which reflects structural encoding of facial features, can be modulated by emotional expressions. Owing to its similar latency …
A Dynamic Electrical Scheme for the optimal reconfiguration of PV modules under non-homogeneous solar irradiation
2012
This paper presents a strategy for the maximization of the output power of photovoltaic (PV) systems under non homogeneous solar irradiation by means of automatic reconfiguration of the PV arrays layout. The innovation of the proposed approach is the employment of a simple Dynamic Electrical Scheme (DES), allowing a large number of possible modules interconnection, to be installed between the PV generator and the inverter. The models of the PV generator and of the DES have been realized and simulated with Simulink (Dynamic System Simulation for MATLAB). The attained experimental results appear to be quite interesting in terms of the attainable benefit in power and thus energy terms. The lim…
Kuulotiedon käsittely 5-6-vuotiailla : kuulovasteet, niiden paikantaminen ja yhteys käyttäytymistason testien tuloksiin
2011
Tutkimuksen aiheena oli 5—6-vuotiaiden lasten kuulotiedon käsittely ja sen kehittyminen. Tutkit-tavina oli 25 tyypillisesti kehittynyttä lasta: 13 tyttöä ja 12 poikaa. 5-vuotiaita oli yhdeksän, 6-vuotiaita oli 16. Tutkittavat oli rekrytoitu Jyväskylästä ja sen lähialueilta Väestörekisterikeskukselta saatujen tietojen pohjalta. Tutkimuksessa tehtiin sekä EEG-mittaus että käyttäytymistason testejä. EEG-mittauksessa käytettiin ns. oddball-asetelmaa, jossa taajuudeltaan 500 Hz:n siniäänen seassa soitettiin poikkeavana ärsykkeenä 425 Hz:n siniääntä. Käyttäytymistason testejä oli kaksi: Ensimmäisessä tutkittavien piti kuunnella kolmen siniäänen joukosta, mikä äänistä oli taajuudeltaan korkeampi k…