RESUMEN

Evidence suggests different mismatch negativity (MMN) and P3a responses in individuals with autism spectrum disorder (ASD). Since unaffected siblings shared aberrant neurocognition and brain connectivity with ASD probands, this study investigated MMN and P3a responses in unaffected siblings and explored its neurocognitive implications and effects modifiers. We assessed 43 unaffected siblings of ASD probands and 64 non-autistic comparisons (NTC) using MMN and P3a on both frequency and duration oddball paradigms. The amplitude and latency of MMN and P3a were compared between unaffected siblings and NTC, and validated in 67 ASD probands. In addition, the neurocognitive correlates of MMN and P3a parameters were explored in attention performance, spatial working memory (SWM), and visual research via the tasks of the Conners' Continuous Performance Test and the Cambridge Neuropsychological Test Automated Battery. Compared to NTC, unaffected siblings and ASD probands presented a shorter MMN latency. The P3a amplitude of the duration paradigm (dP3a) was correlated with fewer commission errors, fewer SWM total errors, higher detectability, and more correct responses on visual search tasks. In addition, the dP3a amplitude significantly interacted with sibship, age, and full-scale IQ to predict attention performance, SWM total errors, and total correct response on visual search. Findings suggest that unaffected siblings of ASD may have earlier brain responses upon novelty discrimination. P3a amplitude may correlate with better neurocognitive performance, but the effect was moderated by sibship, age, and intelligence.

RESUMEN

BACKGROUND: To investigate the characteristics of mismatch negativity (MMN) in terms of latency and amplitude in children with bilateral congenital microtia using a Bone conduction implant (Bonebridge), and to explore the relationship between cortical level auditory discrimination, speech perception, and psychosocial well-being. METHODS: This descriptive, observational, cross-sectional study compared three groups: eight children with bilateral congenital microtia and Bonebridge implants (bilateral group), eight children with unilateral congenital microtia and no hearing aids (unilateral group), and eight children with normal hearing (NH group). Participants underwent MMN evaluation using a classic oddball paradigm with a pure tone burst stimulus, featuring a 1000 Hz standard stimulus and a 1200 Hz deviant stimulus, presented in a sound field at 65 dBHL. Additionally, speech perception tests, the Meaningful Use of Speech Scale (MUSS), and psychosocial status questionnaires, including the Social Anxiety Scale for Children (SASC) and the Children's Loneliness Scale (CLS), were administered to all subjects. RESULTS: The bilateral group's average MMN latency was 241.23 ±â€¯29.47 ms, and the unilateral group's was 209.96 ±â€¯54.32 ms, both significantly longer than the NH group's 146.05 ±â€¯15.73 ms (p < 0.0001, F=3.509, 95 % CI 68.09 to 122.3 and p = 0.0097, F=11.92, 95 % CI 18.07 to 109.8, respectively). However, no significant difference was found in MMN latency between the bilateral and unilateral groups (p = 0.202, F=3.397, 95 % CI -18.84 to 81.36). The unilateral group scored significantly higher on the MUSS (38.63 ±â€¯1.41 vs. 30.75 ±â€¯3.80, p = 0.0001, F=7.276, 95 % CI -11.16 to -4.590), had lower CLS scores (47.13 ±â€¯8.13 vs. 58.25 ±â€¯8.39, p = 0.024, F=1.065, 95 % CI 1.652 to 20.60), and lower SASC scores (4.13 ±â€¯2.09 vs. 6.50 ±â€¯2.25, p = 0.062, F=1.204, 95 % CI -0.138 to 4.89) compared to the bilateral group. MMN latency in the bilateral group correlated with SASC scores. CONCLUSION: The MMN latency in congenital microtia patients may serve as an indicator of central auditory discrimination capabilities. In children with bilateral congenital microtia and Bonebridge implants, MMN latency can reflect social anxiety conditions to a certain degree.

RESUMEN

Estonian is a quantity language with both a primary duration cue and a secondary pitch cue, whereas Chinese is a tonal language with a dominant pitch use. Using a mismatch negativity experiment and a behavioral discrimination experiment, we investigated how native language background affects the perception of duration only, pitch only, and duration plus pitch information. Chinese participants perceived duration in Estonian as meaningless acoustic information due to a lack of phonological use of duration in their native language; however, they demonstrated a better pitch discrimination ability than Estonian participants. On the other hand, Estonian participants outperformed Chinese participants in perceiving the non-speech pure tones that resembled the Estonian quantity (i.e., containing both duration and pitch information). Our results indicate that native language background affects the perception of duration and pitch and that such an effect is not specific to processing speech sounds.

Asunto(s)

RESUMEN

Perceptual systems heavily rely on prior knowledge and predictions to make sense of the environment. Predictions can originate from multiple sources of information, including contextual short-term priors, based on isolated temporal situations, and context-independent long-term priors, arising from extended exposure to statistical regularities. While the effects of short-term predictions on auditory perception have been well-documented, how long-term predictions shape early auditory processing is poorly understood. To address this, we recorded magnetoencephalography data from native speakers of two languages with different word orders (Spanish: functor-initial vs Basque: functor-final) listening to simple sequences of binary sounds alternating in duration with occasional omissions. We hypothesized that, together with contextual transition probabilities, the auditory system uses the characteristic prosodic cues (duration) associated with the native language's word order as an internal model to generate long-term predictions about incoming non-linguistic sounds. Consistent with our hypothesis, we found that the amplitude of the mismatch negativity elicited by sound omissions varied orthogonally depending on the speaker's linguistic background and was most pronounced in the left auditory cortex. Importantly, listening to binary sounds alternating in pitch instead of duration did not yield group differences, confirming that the above results were driven by the hypothesized long-term 'duration' prior. These findings show that experience with a given language can shape a fundamental aspect of human perception - the neural processing of rhythmic sounds - and provides direct evidence for a long-term predictive coding system in the auditory cortex that uses auditory schemes learned over a lifetime to process incoming sound sequences.

Asunto(s)

RESUMEN

Cognitive impairment associated with schizophrenia (CIAS) and related deficits in learning (plasticity) are amongst the leading causes of disability in schizophrenia. Despite this, there are no FDA approved treatments for CIAS, and the development of treatments has been limited by numerous Phase II/III failures of compounds that showed initial promise in small-scale studies. N-methyl-d-aspartate-type glutamate receptors (NMDAR) have been proposed to play an important role in schizophrenia; moreover, NMDAR has a well characterized role in cognition, learning and neuroplasticity. We review prior published clinical trials in CIAS focusing on NMDAR modulator treatments, focusing on published and recent developments of the use of novel NMDAR-modulating treatments for CIAS both alone and combined with plasticity/learning paradigms to enhance learning. We will use this discussion of prior studies to highlight the importance of incorporating pharmacodynamic target engagement biomarkers early in treatment development, which can help predict which compounds will succeed or fail in Phase III. A range of direct and indirect NMDAR modulators will be covered, including d-serine, d-cycloserine, memantine, glycine and "first generation" glycine transport inhibitors (GTI, e.g. sarcosine and bitopertin), as well as recent positive studies of iclepertin, a novel GTI and luvadaxistat, a D-amino acid oxidase inhibitor (DAAO-I) that increases brain d-serine levels and indirect non-invasive brain stimulation NMDAR modulating treatments. Several examples of successful use of pharmacodynamic target engagement biomarkers for dose/drug discovery will be emphasized, including mismatch negativity (MMN), auditory steady state (ASSR) and time-frequency event-related potential (TF-ERP) approaches.

RESUMEN

Background: Although impaired auditory mismatch negativity (MMN) has consistently been found in individuals with schizophrenia, there are few and inconsistent reports on nonclinical individuals with schizotypy. To date, no studies have thoroughly assessed MMN with different degrees of deviant oddballs in nonclinical schizotypal samples. The aim of this study was to examine the extent of duration MMN (dMMN) amplitudes under two deviant duration conditions (large and small) in nonclinical participants with high schizotypal traits. Methods: An extreme-group design was utilized, in which 63 participants from the schizotypy and control groups were selected from a pool of 1519 young adults using the Schizotypal Personality Questionnaire (SPQ). MMN was measured using passive duration oddball paradigms. Basic demographic information and musical backgrounds were assessed and matched, while depression and anxiety were evaluated and controlled for. The repeated measures analysis of covariance was utilized to evaluate differences in dMMN between groups. The Bonferroni correction was applied for multiple comparisons. Partial correlation and multiple linear regression analyses were conducted to investigate the association between dMMN amplitudes and SPQ scores. Results: The amplitudes of dMMN at Cz were significantly increased under the large deviance condition in nonclinical schizotypal individuals (F = 4.36, p = .04). Large-deviance dMMN amplitudes at Fz were positively correlated with mild cognitive-perceptual symptoms in the control group (rp = .42, p = .03). However, as schizophrenia-like symptoms worsened and approached the clinical threshold for schizophrenia, small-deviance dMMN amplitudes at Cz showed negative associations with the cognitive-perceptual factor in the schizotypy group (rp = -.40, p = .04). Conclusion: These results suggest the importance of considering the degree of deviation in duration when implementing the auditory oddball paradigm among nonclinical participants with schizotypal traits. In addition, our findings reveal a potential non-linear relationship between bottom-up auditory processing and the positive dimension of the schizophrenia spectrum.

RESUMEN

Using electroencephalography (EEG) to examine the simple mismatch negativity (MMN), a marker of auditory cortex function, has been of great interest in the exploration of biomarkers for psychotic illness. Despite many studies reporting MMN deficits in chronic schizophrenia, there are inconsistent reports of MMN reductions in the early phases of psychotic illness, suggesting the MMN elicited by traditional paradigms may not be a sensitive enough measure of vulnerability to be used as a biomarker. Recently, a more computationally complex measure of auditory cortex function (the complex mismatch negativity; cMMN) has been hypothesized to provide a more sensitive marker of illness vulnerability. The current study employed a novel dual rule paradigm, in which two pattern rules are established and violated, to examine the cMMN in 14 individuals with early phase psychosis (EPP, < 5 years illness) and 15 healthy controls (HC). Relationships between cMMN waveforms, symptom severity, and measures of functioning were explored. We found reductions of cMMN amplitudes at the site of maximal amplitude in EPP (p = .017) with large effect sizes (Hedges' g = 0.96). This study is an early step in the exploration of the cMMN as a biomarker for psychosis. Our results provide evidence that the dual rule cMMN paradigm shows promise as a method for cMMN elicitation that captures more subtle neurofunctional changes in the early stages of illness.

RESUMEN

Background: Cognitive abnormalities associated with electroconvulsive therapy (ECT) are limited to the first few days after treatment. Mismatch negativity (MMN) is an event-related potential that reflects an automatic auditory change detection process under nonattention conditions and cognitive function in psychotic disorders and may be trait- or state-dependent. This study aimed to report the changes in MMN and cognitive function after two ECT treatments in a female patient who underwent maintenance ECT for atypical psychosis. Case Presentation: A 67-year-old Japanese woman with atypical psychosis was admitted to our hospital for the maintenance of ECT. She received two ECT treatments. We measured her duration-MMN (MMN-D) at baseline, the day after two ECT treatments, and approximately 40 days after the two ECT treatments. After the two ECT treatments, the peak latency of the MMN on the following day was delayed compared with that before the first ECT treatment. Forty days after the two ECT treatments, the peak latency reverted to the baseline. The Brief Assessment of Cognition in Schizophrenia scores measured at the same time point also showed a similar temporary decrease in scores. Conclusion: Peak latency prolongation in MMN-D may reflect transient cognitive abnormalities after ECT. MMN can be useful to evaluate cognitive dysfunction, one of the adverse events of ECT. However, future studies are needed to examine the reproducibility and to examine the results in diseases other than atypical psychosis.

RESUMEN

BACKGROUND AND OBJECTIVES: The dorsal cochlear nucleus (DCN) is the interaction site of auditory and somatosensory system inputs. According to the stochastic resonance theory, hearing loss increases the neural activity of the somatosensory system in the DCN and causes tinnitus. it is possible to modulate this neural hyperactivity by applying random noise through the auditory and somatosensory systems (bimodal stimulation). Therefore, this study aimed to investigate the effectiveness of the bimodal intervention based on the theory of stochastic resonance. METHODS: The study divided 34 participants into unimodal and bimodal groups with 17 subjects in each. The bimodal group received customized acoustic stimulation along with transcutaneous auricular vagus nerve stimulation (tAVNS) and the unimodal group received customized acoustic stimulation along with tAVNS as a sham. The treatment sessions in both groups were 6 sessions and each session lasted for 20 min. The participants were evaluated before, immediately after, and one month after the completion of the intervention sessions, using the Tinnitus Handicap Inventory (THI) questionnaire and the mismatch negativity (MMN) test. RESULTS: After the intervention sessions, the results indicated a statistically significant decrease in THI scores and a significant increase in the MMN amplitude in the bimodal group compared to the unimodal group. No significant changes in MMN latency were observed between the two groups. These changes were stable in the one-month follow-up visit. CONCLUSIONS: Our study showed that bimodal stimulation is a better intervention option compared to unimodal stimulation. Bimodal stimulation may be an effective intervention method for some subjects with tinnitus, especially people with hearing loss who have tonal tinnitus.

RESUMEN

The current study investigated the effect of lower frequency input on stream segregation acuity in older, normal hearing adults. Using event-related brain potentials (ERPs) and perceptual performance measures, we previously showed that stream segregation abilities were less proficient in older compared to younger adults. However, in that study we used frequency ranges greater than 1500 Hz. In the current study, we lowered the target frequency range below 1500 Hz and found similar stream segregation abilities in younger and older adults. These results indicate that the perception of complex auditory scenes is influenced by the spectral content of the auditory input and suggest that lower frequency ranges of input in older adults may facilitate listening ability in complex auditory environments. These results also have implications for the advancement of prosthetic devices.

Asunto(s)

RESUMEN

Sound localization in the front-back dimension is reported to be challenging, with individual differences. We investigated whether auditory discrimination processing in the brain differs based on front-back sound localization ability. This study conducted an auditory oddball task using speakers in front of and behind the participants. We used event-related brain potentials to examine the deviance detection process between groups that could and could not discriminate front-back sound localization. The results indicated that mismatch negativity (MMN) occurred during the deviance detection process, and P2 amplitude differed between standard and deviant locations in both groups. However, the latency of MMN was shorter in the group that could discriminate front-back sounds than in the group that could not. Additionally, N1 amplitude increased for deviant locations compared to standard ones only in the discriminating group. In conclusion, the sensory memories matching process based on traces of previously presented stimuli (MMN, P2) occurred regardless of discrimination ability. However, the response to changes in the physical properties of sounds (MMN latency, N1 amplitude) differed depending on the ability to discriminate front-back sounds. Our findings suggest that the brain may have different processing strategies for the two directions even without subjective recognition of the front-back direction of incoming sounds.

Asunto(s)

RESUMEN

Over the past decade, there has been extensive research on the mismatch negativity (MMN) and its promise as a biomarker of illness in people with schizophrenia (SZ). Nevertheless, when attempting to assess the early stages of illness progression, the utility of MMN has been inconsistent. Recently, researchers have been investigating a more advanced MMN paradigm (the complex MMN [cMMN]) which is believed to index higher-order cognitive processing and has been suggested to be a more effective indicator of the early phases of SZ. The cMMN is defined as a paradigm that relies on alterations within a pre-established pattern of stimuli. In this meta-analysis, we investigated cMMN deficits in individuals with SZ, including an analysis involving those in the first 5 years of illness. Our search also included individuals with bipolar disorder who experience psychosis; however, no related papers were found and thus, no findings are reported. Our findings indicate a small/moderate effect (d = 0.47), suggesting that individuals with SZ exhibit reduced cMMN amplitudes compared to individuals without SZ. Interestingly, this effect seems to be more pronounced in individuals within the first 5 years of their illness (d = 0.58), suggesting that cMMN might be a more sensitive biomarker in the early phases of SZ compared to traditional paradigms.

RESUMEN

Microstates are transient scalp configurations of brain activity measured by electroencephalography (EEG). The application of microstate analysis in magnetoencephalography (MEG) data remains challenging. In one MEG dataset (N = 113), we aimed to identify MEG microstates at rest, explore their brain sources, and relate them to changes in brain activity during open-eyes (ROE) or closed-eyes resting state (RCE) and an auditory Mismatch Negativity (MMN) task. In another dataset of simultaneously recorded EEG-MEG data (N = 21), we investigated the association between MEG and EEG microstates. Six MEG microstates (mMS) provided the best clustering of resting-state activity, each linked to different brain sources: mMS 1-2: left/right occipito-parietal; mMS 3: fronto-temporal; mMS 4: centro-medial; mMS 5-6: left/right fronto-parietal. Increases in occipital alpha power in RCE relative to ROE correlated with greater mMS 1-2 time coverage (τbs < 0.20, ps > .002), while the lateralization of deviance detection in MMN was associated with mMS 5-6 time coverage (τbs < 0.16, ps > .012). No temporal correlation was found between EEG and MEG microstates (ps > .05), despite some overlap in brain sources and global explained variance between mMS 2-3 and EEG microstates B-C (rs > 0.60, ps < .002). Hence, the MEG signal can be decomposed into microstates, but mMS brain activity clustering captures phenomena different from EEG microstates. Source reconstruction and task-related modulations link mMS to large-scale networks and localized activities. Thus, mMSs offer insights into brain dynamics and task-specific processes, complementing EEG microstates in studying physiological and dysfunctional brain activity.

Asunto(s)

RESUMEN

OBJECTIVE: It is important to discriminate different headaches in clinical practice, and neurocognitive biomarkers may serve as objective tools. Several reports have suggested potential cognitive impairment for primary headaches, whereas cognitions within specific domains remain elusive, e.g., emotional processing. In this study, we aimed to characterize processing of facial expressions in migraine and tension-type headache (TTH) by analyzing expression-related visual mismatch negativity (EMMN) and explored whether their processing patterns were distinct. METHODS: Altogether, 73 headache patients (20 migraine with aura (MA), 28 migraine without aura (MwoA), 25 TTH) and 27 age-matched healthy controls were recruited. After a battery of mood/neuropsychological evaluations, an expression-related oddball paradigm containing multiple models of neutral, happy and sad faces was used to investigate automatic emotional processing. RESULTS: We observed cognitive impairment in all headache patients, especially in attention/execution subdomains, but no discrepancy existed among different headaches. Although analyses of P1/N170 did not reach significant levels, amplitude of early and late EMMN was markedly diminished in MA and MwoA compared with controls and TTH, regardless of happy or sad expression. Moreover, sad EMMN was larger (more negative) than happy EMMN only in controls, while not in all headache groups. CONCLUSIONS: Our findings implied that migraine, rather than TTH, might lead to more severe impairment of automatic emotional processing, which was manifested as no observable EMMN elicitation and disappearance of negative bias effect. The EMMN component could assist in discrimination of migraine from TTH and diagnosis of undefined headaches, and its availability needed further validations.

RESUMEN

In the flanker task, the behavioral performance for incompatible stimuli is worse in the mostly compatible (rare) condition than in the equiprobable condition. Furthermore, incompatible stimuli evoke visual mismatch negativity (VMMN) when comparing the rare and equiprobable conditions. Compatible and incompatible stimuli differ in terms of their shape and type. This study aimed to examine whether VMMN evoked by rare incompatible stimuli were associated with the shape or type of the stimulus. In a modified version of the flanker task, stimuli were manipulated by two shapes (typical or peculiar) and two types (compatible or incompatible): typical compatible stimuli (< < < < < and > > > > >), typical incompatible stimuli (> > < > > and < < > < <), peculiar compatible stimuli (+ < < < + and + > > > +), and peculiar incompatible stimuli (+ > < > + and + < > < +). In the rare condition, typical incompatible, peculiar compatible, and peculiar incompatible stimuli were presented with a probability of 10%, whereas all the stimuli were presented equally in the equiprobable condition. Right posterior negativity from 200 to 250 ms was significantly more negative in the rare condition than in the equiprobable condition for typical and peculiar incompatible stimuli; however, this difference was not observed for peculiar compatible stimuli. VMMN was significantly more negative for typical and peculiar incompatible stimuli than for peculiar compatible stimuli, and was not significantly different between typical and peculiar incompatible stimuli. These findings suggest that VMMN for incompatible stimuli is associated with the type rather than the shape of the stimulus.

Asunto(s)

RESUMEN

BACKGROUND: Dysregulated prediction error-signalling may explain auditory hallucinations in schizophrenia (SZ-AH). Roving mismatch negativity (rMMN) is an event-related potential (ERP) index where the deviant tone becomes the new standard with repetitions. Longer repetitions of standard stimuli yield a more positive sensory-adaptation response (Repetition Positivity-RP), elicit a stronger deviance-detection when interrupted (deviant negativity-DN), and the difference waveform between them reflects the strength of prediction-error signalling (mismatch negativity-MMN). METHODS: Twenty-three SZ-AH patients and twenty-three healthy controls (HC) underwent rMMN assessment. Various standard stimuli were repeated in sets of 3, 8 and 33 yielding three components for RP (RP3, RP8, RP33), DN (DN3, DN8, DN33), and MMN (MMN3, MMN8, MMN33). Amplitudes and latencies were compared across groups. Correlation between (a) rMMN amplitudes and latencies, and clinical variables in SZ-AH, and (b) the RP-DN amplitude pair for all three repetition sets (3, 8, 33) were also examined. RESULTS: All DN and MMN33 amplitudes were significantly suppressed in SZ-AH, while RP amplitudes were not. MMN33 latency was significantly longer in SZ-AH than HC. A few amplitudes and latencies significantly correlated with the frequency of AH. HC showed a significant positive correlation between RP-DN amplitude pairs for sets of 3 and 8 but not for 33; SZ-AH group's correlation profile was opposite to this. DISCUSSION: The link between repetition-dependent sensory-adaptation and deviance-detection is perturbed in SZ-AH. The unimpaired RP profile in SZ-AH is due to potential interference of AH with auditory information processing, and does not indicate a preserved short-term plasticity of the echoic memory trace.

RESUMEN

Mismatch negativity (MMN) is automatically elicited by incoming sound deviation compared to the neural representation of preceding homogenous sounds stored in the brain's auditory sensory memory. This study aimed to assess time-functional deviation sensitivity in auditory sensory memory associated with a temporal window of integration (TWI) of 160-170 msec in patients with schizophrenia. To this end, we measured the magnetic counterpart of the MMN (MMNm) in 20 patients with schizophrenia on medication and 20 healthy age-matched adults as a control group responding to an omitted tone segment incorporated into a complex sound of 176 ms duration corresponding to the TWI duration. Overall, the magnitude of the MMNm was smaller in the patients with schizophrenia than in the healthy control group. The peak latency of the MMNm was prolonged in the latter omitted segments for both groups, but to a greater extent in patients with schizophrenia. These results indicate that deviation detection is impaired in the later part of the TWI, corresponding to the duration of auditory sensory memory in patients with schizophrenia. Thus, the specific impairment of MMN in response to duration deviants (duration MMN), as previously reported, might result from a damaged mechanism in the later part of the TWI of sensory memory, suggesting that a decline in sensory memory causes distorted perception or disturbances in cognitive function in patients with schizophrenia.

RESUMEN

The cortical generators of the pure tone MMN and P300 have been thoroughly studied. Their nature and interaction with respect to phoneme perception, however, is poorly understood. Accordingly, the cortical sources and functional connections that underlie the MMN and P300 in relation to passive and active speech sound perception were identified. An inattentive and attentive phonemic oddball paradigm, eliciting a MMN and P300 respectively, were administered in 60 healthy adults during simultaneous high-density EEG recording. For both the MMN and P300, eLORETA source reconstruction was performed. The maximal cross-correlation was calculated between ROI-pairs to investigate inter-regional functional connectivity specific to passive and active deviant processing. MMN activation clusters were identified in the temporal (insula, superior temporal gyrus and temporal pole), frontal (rostral middle frontal and pars opercularis) and parietal (postcentral and supramarginal gyrus) cortex. Passive discrimination of deviant phonemes was aided by a network connecting right temporoparietal cortices to left frontal areas. For the P300, clusters with significantly higher activity were found in the frontal (caudal middle frontal and precentral), parietal (precuneus) and cingulate (posterior and isthmus) cortex. Significant intra- and interhemispheric connections between parietal, cingulate and occipital regions constituted the network governing active phonemic target detection. A predominantly bilateral network was found to underly both the MMN and P300. While passive phoneme discrimination is aided by a fronto-temporo-parietal network, active categorization calls on a network entailing fronto-parieto-cingulate cortices. Neural processing of phonemic contrasts, as reflected by the MMN and P300, does not appear to show pronounced lateralization to the language-dominant hemisphere.

Asunto(s)

RESUMEN

OBJECTIVE: Sensory intelligence in the brain helps listeners automatically extract abstract auditory rules formed by invariant acoustic features from complex speech sound streams, presumably serving as the neural basis for speech comprehension. However, whether this intelligence is deficient in children with cochlear implants (CIs) remains unclear. METHODS: Mandarin Chinese monosyllables shared a flat lexical tone contour to form an abstract auditory rule but differed in other acoustic features to construct a complex speech sound stream. The abstract rule was occasionally violated by monosyllables with a rising or falling lexical tone. RESULTS: In normal hearing (NH) children, the abstract auditory rule could be extracted, as revealed by a mismatch negativity (MMN) and a late discriminative negativity (LDN). However, the MMN and LDN were only evoked in CI children with good hearing and speech performance. NH children with a higher speech perception or spatial hearing score had a greater MMN. The LDN was attenuated with increasing age in NH children. CONCLUSIONS: The sensory intelligence for extraction of auditory abstract rules, associated with speech perception, is deficient in CI children. This intelligence may gradually develop during childhood and adolescence. SIGNIFICANCE: Deficient sensory intelligence in CI children may aid in understanding poor speech comprehension in complex environments.

Asunto(s)

RESUMEN

OBJECTIVE: Tinnitus retraining therapy (TRT) has been widely used in tinnitus management. However, its efficacy is often assessed through subjective methods. Here, we aimed to assess potential neural changes following TRT using mismatch negativity (MMN). DESIGN: Chronic tinnitus (>6 months) patients participated in a six-month TRT program. We collected tinnitus psychoacoustic features and gathered the tinnitus handicap inventory (THI) before and after TRT. We also used a multi-featured paradigm, including frequency, intensity, duration, location and silent gap deviants, to elicit MMN response before and after TRT. Data were analyzed retrospectively. STUDY SAMPLE: The study involved 26 chronic tinnitus patients. RESULTS: Post-TRT measurements showed that MMN amplitudes significantly increased for all deviant conditions (p ≤ .03). However, we did not find a significant difference in MMN latencies for all deviant conditions (p ≥ .13). The THI scores of the patients significantly decreased following the TRT program (p < 0.001). Our results reveal improved subjective tinnitus perception following the TRT program. CONCLUSION: These findings indicate that TRT might be a viable alternative in tinnitus management. The greater MMN amplitudes and improved subjective tinnitus perception raise the possibility that MMN can be a useful tool in tinnitus research and tinnitus patient follow-up.