MMN Amplitude Research Articles

Hyperacusis questionnaire and event-related potential correlation in migraine patients

This study aims to investigate auditory hypersensitivity and cortical function in migraine patients using the Hyperacusis Questionnaire and the Event-Related Potential (ERP) technique. The study analyzes alterations in the latency and amplitude of the event-related potentials MMN and P300 components. The findings contribute to a better understanding of the physiological relationship between migraine and auditory hypersensitivity. Seventeen migraine patients were admitted to the outpatient clinic of the Department of Otorhinolaryngology-Head and Neck Surgery at Peking University People’s Hospital from June 2023 to September 2023. Nineteen matched healthy subjects were also selected. All participants underwent the pure tone audiometry and the auditory brainstem response test to determine hearing thresholds, the Hyperacusis Questionnaire, the Tinnitus Handicap Inventory, and an ERP examination. The Oddball classical paradigm was used as the stimulation task, and electroencephalography signals were recorded synchronously. The scores of the Hyperacusis Questionnaire, latency and amplitude of MMN and P300 component were compared between the migraine group and the control group, and their correlation was analyzed. The latency of MMN at the Fz and Cz sites in migraine patients was significantly shorter than that in the control group (P < 0.05), and the amplitudes were significantly higher than those in the control group (P < 0.05). The variances in latency and amplitude of P300 at Cz and Pz sites in migraine patients were not statistically significant when compared with the control group. (P > 0.05). The Hyperacusis Questionnaire was negatively correlated with MMN latency, with a correlation coefficient of − 0.374 (P = 0.025), and positively correlated with MMN amplitude, with a correlation coefficient of 0.378 (P = 0.023). There was no significant similarity between the Hyperacusis Questionnaire and P300 latency and amplitude (P > 0.05). Overall, auditory hypersensitivity was enhanced in individuals with migraines compared to healthy individuals, leading to faster information processing, while there may be less impairment in cognitive function.

A study on neural changes induced by sauna bathing: Neural basis of the "totonou" state.

Saunas are becoming increasingly popular worldwide, being an activity that promotes relaxation and health. Intense feelings of happiness have been reported shortly after enjoying a hot sauna and cold water, what is known in Japan as the "totonou" state. However, no research has investigated what occurs in the brain during the "totonou" state. In the present study, participants underwent a sauna phase, consisting of three sets of alternating hot sauna, cold water, and rest. We elucidated changes in brain activity and mood in the "totonou" state by measuring and comparing brain activity and emotional scales before and after the sauna phase and during the rest phase in each set. We found significant increases in theta and alpha power during rest and after the sauna phase compared to before the sauna phase. Moreover, in an auditory oddball task, the p300 amplitude decreased significantly and MMN amplitude increased significantly after the sauna phase. The increase in MMN indicates higher activation of the pre-attentional auditory process, leading to a decrease in attention-related brain activity P300. Hence, the brain reaches in a more efficient state. Further, the response time in behavioral tasks decreased significantly. In addition, the participants' subjective responses to the questionnaire showed significant changes in physical relaxation and other indicators after being in the sauna. Finally, we developed an artificial intelligence classifier, obtaining an average accuracy of brain state classification of 88.34%. The results have potential for future application.

Pre- to Postoperative Longitudinal Follow-up of Phoneme Perception in Glioma Patients: Evidence from the Mismatch Negativity and P300

ABSTRACT Background and Aims Glioma growth in eloquent language areas induces adaptive activation changes in the language network. The present study aimed to (1) investigate the pre- to postoperative evolution of neural phoneme perception processes in glioma patients and (2) assess if event-related potentials (ERPs) reflecting phoneme perception can provide added value to the diagnostic approach in individuals undergoing awake surgery. Methods and Procedures In five persons undergoing an awake craniotomy for the resection of a glioma, pre- and postoperative behavioural language assessment (Aachen Aphasia Test, Comprehensive Aphasia Test and Boston Naming Test) and electrophysiological investigation of phoneme perception was performed. For the latter, ERPs were obtained through the administration of an inattentive (Mismatch Negativity; MMN) and attentive (P300) oddball paradigm containing a phonemic articulation place contrast during EEG recording. Outcomes and Results Aberrant phoneme categorization processing was evidenced in all five participants preoperatively based on the MMN and P300 amplitude and latency. Moreover, mild behavioural impairments were found in four participants at this time. Postoperatively, three out of five participants reached behavioural ceiling effects, while four individuals displayed normalization of electrophysiological measures. Conclusions While neural processing of phoneme contrasts was preoperatively affected by glioma-induced disturbances, a high potential for postsurgical plasticity was shown. As four participants presented with a high grade glioma, tumour grade might partially account for this pattern. Addition of electrophysiological tests to the language assessment could provide benefits in both the pre- and postoperative clinical diagnostic approach in glioma patients. These preliminary results need validation in a larger sample.

Distinct Neural Resource Involvements but Similar Hemispheric Lateralization Patterns in Pre-Attentive Processing of Speaker's Identity and Linguistic Information.

The speaker's identity (who the speaker is) and linguistic information (what the speaker is saying) are essential to daily communication. However, it is unclear whether and how listeners process the two types of information differently in speech perception. The present study adopted a passive oddball paradigm to compare the identity and linguistic information processing concerning neural resource involvements and hemispheric lateralization patterns. We used two female native Mandarin speakers' real and pseudo-Mandarin words to differentiate the identity from linguistic (phonological and lexical) information. The results showed that, in real words, the phonological-lexical variation elicited larger MMN amplitudes than the identity variation. In contrast, there were no significant MMN amplitude differences between the identity and phonological variation in pseudo words. Regardless of real or pseudo words, the identity and linguistic variation did not elicit MMN amplitudes differences between the left and right hemispheres. Taken together, findings from the present study indicated that the identity information recruited similar neural resources to the phonological information but different neural resources from the lexical information. However, the identity and linguistic information processing did not show a particular hemispheric lateralization pattern at an early pre-attentive speech perception stage. The findings revealed similarities and differences between linguistic and non-linguistic information processing, contributing to a better understanding of speech perception and spoken word recognition.

Interaction effects of the 5-HTT and MAOA-uVNTR gene variants on pre-attentive EEG activity in response to threatening voices

Both the serotonin transporter polymorphism (5-HTTLPR) and the monoamine oxidase A gene (MAOA-uVNTR) are considered genetic contributors for anxiety-related symptomatology and aggressive behavior. Nevertheless, an interaction between these genes and the pre-attentive processing of threatening voices –a biological marker for anxiety-related conditions– has not been assessed yet. Among the entire sample of participants in the study with valid genotyping and electroencephalographic (EEG) data (N = 140), here we show that men with low-activity MAOA-uVNTR, and who were not homozygous for the 5-HTTLPR short allele (s) (n = 11), had significantly larger fearful MMN amplitudes –as driven by significant larger ERPs to fearful stimuli– than men with high-activity MAOA-uVNTR variants (n = 20). This is in contrast with previous studies, where significantly reduced fearful MMN amplitudes, driven by increased ERPs to neutral stimuli, were observed in those homozygous for the 5-HTT s-allele. In conclusion, using genetic, neurophysiological, and behavioral measurements, this study illustrates how the intricate interaction between the 5-HTT and the MAOA-uVNTR variants have an impact on threat processing, and social cognition, in male individuals (n = 62).

Adjuvant electroconvulsive therapy with antipsychotics is associated with improvement in auditory mismatch negativity in schizophrenia

• Thirty-seven patients with schizophrenia received 8 bifrontal adjuvant ECT treatments with atypical antipsychotics. The frequency and duration MMN of auditory stimuli were measured before and after ECT treatments. The Positive and Negative Syndrome Scale was used to assess clinical symptoms. Cognitive function was assessed using the MATRICS Consensus Cognitive Battery. • At baseline, compared with healthy controls, patients with schizophrenia had a significantly lower amplitude of both MMN-F and MMN-D and significantly longer MMN-D latency. Compared with baseline, the amplitude increased significantly and the latency shortened significantly in patients with schizophrenia, both in frequency and duration MMN after 8 ECT treatments. • The improvement of cognitive function was significantly correlated with the change of MMN latency. There was a significant correlation between the change of MMN amplitude and the change of general psychopathological subscale of PANSS. • MMN may be a biomarker of the effects of ECT on cognitive function in patients with schizophrenia.

The effect of memantine on cortical network function in frontotemporal lobar degeneration is conditional on baseline GABA physiology

AbstractBackgroundFrontotemporal lobar degeneration (FTLD) is associated with deficits to GABA and glutamatergic neurotransmitters, particularly in the frontal cortex. While targeting GABAergic systems has shown to restore frontotemporal deficits in FTLD, little is known whether pharmacological probes of glutamatergic functioning have similar effects in these circuits.MethodTwenty participants with a FTLD‐associated syndrome (11 with PSP, 9 with bvFTD) and 20 healthy‐controls undertook two magnetoencephalography (MEG) sessions with a roving auditory oddball paradigm assessing frontotemporal change detection: (1) session on placebo and (2) after 10mg of oral memantine, which aims to blocks glutamatergic ecotoxicity. The mean amplitude of MEG “mismatch negativity” responses (MMN; standard‐deviants, 125‐175ms) was calculated across gradiometer sensors and for bilateral frontotemporal sources. Glutamate and GABA levels were measured using 7T proton magnetic resonance spectroscopy of the right inferior frontal gyrus (IFG). Frequentist and Bayesian ANOVAs assessed the differential mean MMN responses between controls and patients across placebo and drug conditions. Evoked difference waveforms (standard‐deviants) across the peristimulus time‐window were analysed using random field theory (RFT) (crit p=0.05, FWER) for the interaction effects of interest (i.e. drug session x group and drug x MRS levels).ResultPatients and controls did not demonstrate differential mean MMN amplitudes on placebo at the average‐sensor (p=0.95) or source‐level (p&gt;0.27) (BF10=0.3‐0.5). Across sensors, only controls exhibited a differential drug‐dependent MMN, reflected by a steeper rebound of difference waveforms between 206‐288ms on memantine (Fig 1A; pFWER=0.026, cluster‐level). However, no interaction was found for mean MMNs (p&gt;0.053). Notably, RFT (Fig 1B) and linear mixed models (Fig 1C) identified that greater GABA levels in patients are significantly associated with stronger MMN responses in right‐hemisphere areas under memantine. Glutamate levels did not moderate the mean MMN response to memantine (p&gt;0.065).ConclusionOverall, we show that targeting glutamatergic systems may not lead to a restoration of frontotemporal physiology across patients. However, the effects of memantine are conditional on patient's baseline GABA, suggesting a critical balance between glutamatergic and GABA physiology that may underlie the large‐scale neural deficits in FTLD.

A preliminary study on the negative wave mismatch in patients with unilateral total sudden deafness

Objective:To observe the characteristics of different negativity negativity （MMN） in patients with unilateral sudden deafness, and compare them with normal MMN, in order to provide theoretical reference for discussing the pathogenesis of unilateral sudden deafness and their relationship with the auditory centers, and to provide theoretical basis for the treatment of sudden deafness in the future. Methods:Twenty-six cases of unilateral total sudden deafness were recruited as experimental group, 25 cases of normal healthy people as control group, the MMN inspections was performed respectively, the two groups using classical mode of oddball, standard and deviation stimulate with 1000 Hz and 2000 Hz short pure tone test MMN respectively, to observe the MMN latency and amplitude characteristics, and compare the latent period and amplitude difference between the two groups. Results:Among the 51 subjects, only 1 patient with unilateral total sudden deafness did not elicit MMN waveform, while the rest were all induced. The average incubation period of MMN in the experimental group was （162.03±38.64） ms, the average amplitude was （2.83±1.14）μV, and the mean age was （48.64±10.27） y. While the average incubation period of MMN in the control group was （197.52±27.43） ms, the average amplitude was （2.58±1.07）μV, and the mean age was （45.00±8.20） y. The MMN latency was significantly different between the two groups （P<0.01）. There was no statistical difference in amplitude between the two groups （P>0.05）. There was no statistical difference in age between the two groups （P>0.05）. Conclusion:The latency period of MMN of unilateral total sudden deafness is shorter than that of the control group. It suggests that the auditory center function of patients with acute sudden deafness has changed, and we speculate that the auditory center of patients with acute sudden deafness may have corresponding emergency changes, so as to make its function have adaptive changes, which will provide further reference for the discussion of the pathophysiological mechanism and treatment of sudden deafness in the future.We speculated that acute unilateral auditory deprivation caused by unilateral total deafness sudden deafness has an impact on cerebral cortical auditory function, which provides further reference for the discussion of pathophysiological mechanism and treatment plan of sudden deafness in the future.

Targeted α7 Nicotinic Acetylcholine Receptor Treatment for the Modulation of Speech MMN in Schizophrenia: An Optimized CDP-Choline and Galantamine Combination Approach Personalized to Baseline-Deviance Detection Levels

α7 nicotinic acetylcholine receptors (nAChR) pathophysiology is associated with sensory and cognitive dysfunction in schizophrenia (SCZ), a multigenic neurodevelopmental disorder. The mismatch negativity event-related potential (MMN-ERP) is sensitive to early deviance detection and sensory memory processing, which are impaired in SCZ and their non-affected relatives. Improvement in MMN amplitudes is associated with clinical and functional outcomes, making this ERP an ideal endophenotype to assess novel pharmacological treatments. As genetics, smoking status, personality, and functioning level were emphasized as trait factors underlying response variability to pharmacological therapies and specific α7 nAChR agonists, the MMN use for participant baseline electrophysiological response stratification is an increasingly applied strategy demonstrating converging evidence of deviance detection improvements in SCZ. Evidence for sensory processing improvements mediated by α7 nAChR-agonists and considering this receptor’s fast desensitization rate, a novel optimized approach combining CDP-choline (a selective α7 agonist) with galantamine (a nAChR positive allosteric modulator) was shown to increase deviance detection in healthy low-baseline groups.

Does working memory protect against auditory distraction in older adults?

BackgroundPast research indicates that when younger adults are engaged in a visual working memory task, they are less distracted by novel auditory stimuli than when engaged in a visual task that does not require working memory. The current study aimed to determine whether working memory affords the same protection to older adults.MethodWe examined behavioral and EEG responses in 16 younger and 16 older adults to distractor sounds when the listeners performed two visual tasks; one that required working memory (W1) and the other that did not (W0). Auditory distractors were presented in an oddball paradigm, participants were exposed to either standard tones (600 Hz: 80%) or various novel environmental sounds (20%).ResultsIt was found that: 1) when presented with novel vs standard sounds, older adults had faster correct response times in the W1 visual task than in the W0 task, indicating that they were less distracted by the novel sound; there was no difference in error rates. Younger adults did not show a task effect for correct response times but made slightly more errors when a novel sound was presented in the W1 task compared to the W0 task. 2) In older adults (but not the younger adults), the amplitude of N1 was smaller in the W1 condition compared to the W0 condition. 3) The working memory manipulation had no effect on MMN amplitude in older adults. 4) For the W1 compared to W0 task, the amplitude of P3a was attenuated for the older adults but not for the younger adults.ConclusionsThese results suggest that during the working memory manipulation older adults were able to engage working memory to reduce the processing of task-irrelevant sounds.

Mismatch Negativity Is Not Always Modulated by Lexicality.

One factor that is commonly thought to influence MMN amplitude is lexicality; multiple studies have shown that real-word deviants elicit larger MMNs than pseudoword deviants. Here, however, we report data from two experiments challenging this assumption. In the first experiment (N = 48), real-word deviants did not elicit more negative MMNs than pseudoword deviants; the acoustic difference between standard and deviant was identical across these comparisons. In this experiment, the pseudoword deviant [pʰa˨˩] differed from a real-word [pʰa˧˥] in tone only; therefore, to test the possibility that the lexicality effect is real but is restricted to pseudowords that differ from real words by at least one segment, we ran a second experiment which included different items and participants, and also included a control comparison in which the pseudoword ([tsʰei˨˩]) differs from all real words by at least one segment (there is no existing Mandarin morpheme pronounced [tsʰei] in any tone). In the second experiment (N = 36), both types of pseudowords failed to elicit less negative MMNs than real words. These findings, together with other recent studies failing to show lexicality effects in MMN, challenge the assumption that wordhood reliably influences MMN amplitude.

Associations of childhood experiences with event-related potentials in adults with autism spectrum disorder

Childhood maltreatment is defined as experiencing of physical, emotional and sexual abuse and neglect in childhood. Maltreatment in childhood leads to substantial psychosocial problems later in life in the general population. Individuals with autism spectrum disorder (ASD) have a higher risk of experiencing stressful and traumatic events, such as maltreatment, during childhood. Although childhood maltreatment reportedly leads to psychosocial problems in adults with ASD, the biological associations between childhood experiences and brain function in this population remain understudied. Here, we evaluated the relationships between childhood experiences and event-related potential (ERP) components during the auditory odd-ball task in adults with ASD (N = 21) and typically developed (TD) individuals (N = 22). We found that the higher the severity of sexual abuse, the larger the amplitude of P300 at Fz, Cz, C3, and C4 in individuals with ASD. Conversely, the severity of child maltreatment was associated with P300 latency at Cz and C3 in TD individuals. Moreover, full IQ was significantly associated with the MMN amplitude at Fz, Cz, C3, and C4 in TD individuals. These findings provide the first evidence that ERPs could be used to study the impacts childhood experiences on the brain of individuals with ASD and that childhood sexual abuse has salient impacts on brain function in this population.

Trajectories of Mismatch Negativity and P3a Amplitude Development From Ages 9 to 16 Years in Children With Risk Factors for Schizophrenia

BackgroundMismatch negativity (MMN) and P3a amplitude reductions are robust abnormalities of sensory information processing in schizophrenia, but they are variably present in different profiles of risk (family history vs. clinical high risk) for the disorder. This study aimed to determine whether these abnormalities characterize children presenting replicated risk factors for schizophrenia, using longitudinal assessment over the ages of 9–16 years in children with multiple replicated antecedents of schizophrenia (ASz) and with family history of schizophrenia (FHx), relative to typically developing (TD) peers. MethodsA total of 105 children (52 female) sampled from the community were assessed at ages 9–12 years and approximately 2 and 4 years later. Linear mixed models were fitted to MMN and P3a peak amplitudes and latencies, with intercept and slope estimates from 32 ASz and 28 FHx children compared with those of 45 TD peers. ResultsIn ASz relative to TD children, MMN amplitude initially increased and then prominently decreased during adolescence. Both ASz and FHx children had greater P3a amplitude than TD children at 11 years, which decreased with age, in contrast to P3a amplitude increasing during adolescence in TD youths. MMN abnormalities were specific to ASz children who continued to present symptoms during follow-up. ConclusionsAge-dependent MMN and P3a abnormalities demarcate adolescent development of ASz and FHx from TD children, with auditory change detection abnormalities specific to ASz children with continuing symptoms and attention-orienting abnormalities characterizing both ASz and FHx risk profiles. Follow-up is required to determine whether these abnormalities index vulnerability for schizophrenia or an illness nonspecific developmental delay.

T15. MISMATCH NEGATIVITY INDICES AS A PROGNOSTIC FACTOR FOR REMISSION IN SCHIZOPHRENIA

BackgroundMismatch negativity (MMN) is an event-related potential component when a sequence of relatively standard stimuli is interrupted by the infrequent presentation of deviant stimuli. MMN is known to be associated with neuro-cognition and functional outcomes. Also, abnormally decreased MMN has often been reported in schizophrenia. Remission and recovery rates are related to the neuro-cognition of patients with schizophrenia. The present study explored the relationship of MMN with remission in patients with schizophrenia.MethodsForty patients with schizophrenia were recruited and divided into two groups, with or without remission, according to the Remission in Schizophrenia Working Group criteria (RSWGcr). For assessments of symptom severity, cognitive function and functional outcome, scale such as Positive and Negative Syndrome Scale (PANSS), K-WAIS-IV, and Global Assessment of Functioning (GAF) were measured. MMN of the patients were evaluated at the frontocentral site. A regression analysis was used to identify the factors that significantly predicted symptom improvement and remission including MMN at frontal site assessed at baseline, and anticipated clinical variables as predictive factors.ResultsMMN amplitudes in frontal sites were further decreased in the groups without remission compared to the groups with remission. MMN amplitude was significantly correlated with measures of symptom change and functional outcome measurements in patients with schizophrenia. Regression analysis revealed that symptom severity and MMN significantly predicted remission in patients with schizophrenia. Symptom improvement significantly predicted PANSS at baseline, illness duration, and antipsychotic dose, as did MMN amplitude at frontal site.DiscussionThis study explored the relationship of MMN with remission in patients with schizophrenia. The remitted patients with schizophrenia showed larger MMN amplitude in frontal electrode site than those of non-remitted patients. MMN in frontal sites was correlated with symptom improvement and functional outcomes through PANSS and GAF scales. The present study found that MMN was significantly correlated with variables related to remission such as PANSS and GAF evaluated at 6 months later. MMN indexes appears to be a promising candidate for predicted factor of remission of schizophrenia.

Stability of mismatch negativity event-related potentials in a multisite study.

ObjectivesMismatch negativity (MMN), an auditory event‐related potential sensitive to deviance detection, is smaller in schizophrenia and psychosis risk. In a multisite study, a regression approach to account for effects of site and age (12–35 years) was evaluated alongside the one‐year stability of MMN.MethodsStability of frequency, duration, and frequency + duration (double) deviant MMN was assessed in 167 healthy subjects, tested on two occasions, separated by 52 weeks, at one of eight sites. Linear regression models predicting MMN with age and site were validated and used to derive standardized MMN z‐scores. Variance components estimated for MMN amplitude and latency measures were used to calculate Generalizability (G) coefficients within each site to assess MMN stability. Trait‐like aspects of MMN were captured by averaging across occasions and correlated with subject traits.ResultsAge and site accounted for less than 7% of MMN variance. G‐coefficients calculated at electrode Fz were stable (G = 0.63) across deviants and sites for amplitude measured in a fixed window, but not for latency (G = 0.37). Frequency deviant MMN z‐scores averaged across tests negatively correlated with averaged global assessment of functioning.ConclusionMMN amplitude is stable and can be standardized to facilitate longitudinal multisite studies of patients and clinical features.

Mismatch negativity to different deviant changes in autism spectrum disorders: A meta-analysis

ObjectiveMismatch negativity (MMN) has been continuously used to evaluate the functional integrity of central auditory processing. However, it still remains inconclusive whether patients with autism spectrum disorder (ASD) demonstrate reduced MMN responses in all deviant types. MethodsTo reconcile the previous controversial findings, we performed a meta-analysis of peer-reviewed MMN articles concerning ASD. The potential moderators regarding different deviant types, diagnosis, and age on the effect sizes (Hedges’ g) were also assessed. ResultsCompared to the controls, ASD patients showed reduced MMN amplitudes (g = −0.37, p = 0.001) and prolonged latencies (g = −0.33, p = 0.041) in response to speech-sound deviants. Children/adolescents with ASD manifested reduced MMN amplitudes in response to tone-duration deviants (g = −0.46, p = 0.014). Furthermore, the results showed significantly shortened MMN latencies to tone-frequency deviants in patients with autism (g = 0.29, p = 0.038) and, in contrast, prolonged MMN latencies (g = −0.74, p = 0.001) in patients with Asperger syndrome. ConclusionMMN deficits are robust in ASD patients, suggesting an altered central ability in auditory discrimination. SignificanceMMN alterations were displayed in different profiles with respect to frequency, duration and phoneme changes.

Impaired P1 Habituation and Mismatch Negativity in Children with Autism Spectrum Disorder.

Passive testing of auditory function is an important objective in individuals with ASD due to known difficulties in understanding and/or following task instructions. In present study the habituation to standard tones following deviants and the auditory discriminative processes were examined in two conditions: electronic and human sounds, in a sample of 16 ASD children. ASD children presented a reduced habituation in the P1 component and a decrease in the amplitude of the mismatch negativity indicating a lower auditory discrimination with respect to controls. MMN amplitude was related to sensory sensitivity. Results suggest an increased activation to repeatedly auditory stimulus and a poor auditory discrimination, for both: electronic and human sounds with consequences on the impaired sensory behavior of ASD subjects.

Sensory processing deficiencies in patients with borderline personality disorder who experience auditory verbal hallucinations

Auditory verbal hallucinations (AVH) are common in patients with borderline personality disorder (BPD). We examined two candidate mechanisms of AVH in patients with BPD, suggested to underlie sensory processing systems that contribute to psychotic symptoms in patients with schizophrenia; sensory gating (P50 ratio and P50 difference) and change detection (mismatch negativity; MMN). Via electroencephalographic recordings P50 amplitude, P50 ratio, P50 difference and MMN amplitude were compared between 23 borderline patients with and 25 without AVH, and 26 healthy controls. Borderline patients with AVH had a significantly lower P50 difference compared with healthy controls, whereas no difference was found between borderline patients without AVH and healthy controls. The groups did not differ on MMN amplitude.The impaired sensory gating in patients with borderline personality disorder who experience AVH implies that P50 sensory gating deficiencies may underlie psychotic vulnerability in this specific patient group. Patients with borderline personality disorder with or without AVH did not have problems with auditory change detection. This may explain why they are spared from the poor outcome associated with negative symptoms and symptoms of disorganization in patients with chronic schizophrenia.

Childhood leukemia survivors exhibit deficiencies in sensory and cognitive processes, as reflected by event-related brain potentials after completion of curative chemotherapy: A preliminary investigation

ABSTRACTObjective: The purpose of this study was to characterize post-chemotherapy sensory, memory, and attention abilities in childhood survivors of acute lymphoblastic leukemia (ALL) to better understand how treatment affects cognitive functioning.Methods: Eight ALL survivors and eight age-matched, healthy children between the ages of 5-11 years participated in the study. Among the ALL survivors, a median of 63 days (range 22-267 days) elapsed between completion of chemotherapy and this assessment. Sounds were presented in an oddball paradigm while recording the electroencephalogram in separate conditions of passive listening and active task performance. To assess different domains of cognition, we measured event-related brain potentials (ERPs) reflecting sensory processing (P1 component), working memory (mismatch negativity [MMN] component), attentional orienting (P3a), and target detection (P3b component) in response to the sounds. We also measured sound discrimination and response speed performance.Results: Relative to control subjects, ALL survivors had poorer performance on auditory tasks, as well as decreased amplitude of the P1, MMN, P3a, and P3b components. ALL survivors also did not exhibit the amplitude gain typically observed in the sensory P1 component when attending to the sound input compared to when passively listening.Conclusions: Atypical responses were observed in brain processes associated with sensory discrimination, auditory working memory, and attentional control in pediatric ALL survivors indicating deficiencies in all cognitive domains compared to age-matched controls.Significance: ERPs differentiated aspects of cognitive functioning, which may provide a useful tool for assessing recovery and risk of post-chemotherapy cognitive deficiencies in young children. The decreased MMN amplitude in ALL survivors may indicate (N-methyl D-aspartate) NMDA dysfunction induced by methotrexate, and thus provides a potential therapeutic target for chemotherapy-associated cognitive impairments.

Mismatch negativity-indexed auditory change detection of speech sounds in early and chronic schizophrenia

Auditory change detection, as indexed by the EEG-derived mismatch negativity, has been demonstrated to be dysfunctional in chronic schizophrenia using both pure-tone and speech (phoneme) sounds. It is unclear, however, whether reduced MMN amplitudes to speech sound deviants are observed within the first 5 years of the illness. The present study investigated MMNs elicited by across-vowel (phoneme) change in early schizophrenia (ESZ; Experiment 1) as well as chronic schizophrenia (CSZ; Experiment 2). In both experiments, clinical and control participants were presented the Finnish phoneme /e/ (standard; P = .90) and the Finnish phoneme /ö/ (deviant; P = .10) within an oddball paradigm. In experiment 2 we report significantly reduced MMN amplitudes in CSZ relative to HCs, but no differences were found when comparing ESZ and HC in experiment 1. Additionally, in our clinical samples, MMN amplitudes were correlated with symptom scores. These findings suggest that early detection of phonetic change may be impaired in chronic schizophrenia, but not early in the progression of the illness. As MMN reductions only emerged in patients with a longer course of illness, and appeared to change with symptom severity, this suggests a dynamic change in the early auditory processing of language over time in schizophrenia.