The mismatch negativity (MMN) response to complex tones and spoken words in individuals with aphasia

Background: The mismatch negativity (MMN) is a fronto-centrally distributed event-related potential (ERP) that is elicited by any discriminable auditory change. It is an ideal neurophysiological tool for measuring the auditory processing skills of individuals with aphasia because it can be elicited even in the absence of attention. Previous MMN studies have shown that acoustic processing of tone or pitch deviance is relatively preserved in aphasia, whereas the basic acoustic processing of speech stimuli can be impaired (e.g., auditory discrimination). However, no MMN study has yet investigated the higher levels of auditory processing, such as language-specific phonological and/or lexical processing, in individuals with aphasia. Aims: The aim of the current study was to investigate the MMN responses of normal and language-disordered subjects to tone stimuli and speech stimuli that incorporate the basic auditory processing (acoustic, acoustic-phonetic) levels of non-speech and speech sound processing, and also the language-specific phonological and lexical levels of spoken word processing. Furthermore, this study aimed to correlate the aphasic MMN data with language performance on a variety of tasks specifically targeted at the different levels of spoken word processing. Methods & Procedures: Six adults with aphasia (71.7 years ±3.0) and six healthy age-, gender-, and education-matched controls (72.2 years ±5.4) participated in the study. All subjects were right-handed and native speakers of English. Each subject was presented with complex harmonic tone stimuli, differing in pitch or duration, and consonant-vowel (CV) speech stimuli (non-word /de:/ versus real word /deI/). The probability of the deviant for each tone or speech contrast was 10%. The subjects were also presented with the same stimuli in behavioural discrimination tasks, and were administered a language assessment battery to measure their auditory comprehension skills. Outcomes & Results: The aphasic subjects demonstrated attenuated MMN responses to complex tone duration deviance and to speech stimuli (words and non-words), and their responses to the frequency, duration, and real word deviant stimuli were found to strongly correlate with performance on the auditory comprehension section of the Western Aphasia Battery (WAB). Furthermore, deficits in attentional lexical decision skills demonstrated by the aphasic subjects correlated with a word-related enhancement demonstrated during the automatic MMN paradigm, providing evidence to support the “word advantage effect”, thought to reflect the activation of language-specific memory traces in the brain for words. Conclusions: These results indicate that the MMN may be used as a technique for investigating general and more specific auditory comprehension skills of individuals with aphasia, using speech and/or non-speech stimuli, independent of the individual's attention. The combined use of the objective MMN technique and current clinical language assessments may result in improved rehabilitative management of aphasic individuals.     

The mismatch negativity (MMN) in basic research of central auditory processing: A review

In the present article, the basic research using the mismatch negativity (MMN) and analogous results obtained by using the magnetoencephalography (MEG) and other brain-imaging technologies is reviewed. This response is elicited by any discriminable change in auditory stimulation but recent studies extended the notion of the MMN even to higher-order cognitive processes such as those involving grammar and semantic meaning. Moreover, MMN data also show the presence of automatic intelligent processes such as stimulus anticipation at the level of auditory cortex. In addition, the MMN enables one to establish the brain processes underlying the initiation of attention switch to, conscious perception of, sound change in an unattended stimulus stream.     

Maturation of frontal and temporal components of mismatch negativity (MMN) in children

The mismatch negativity (MMN) response of auditory ERPs in adults appears to result from several overlapping components involving both frontal and temporal brain areas. Our aim was to test whether a similar configuration could be observed in children, and to examine the maturation rates of the different components. MMN (standard tones: 1000 Hz, deviants: 1100 Hz) was recorded from 28 scalp electrodes in 24 healthy children aged from 5 to 10 and in eight adults for comparison. Scalp current density analysis revealed both temporal and frontal components in children of all ages as well as in adults. Moreover the amplitudes of the temporal components were significantly greater in children than in adults, whereas the frontal components were similar at all ages. The results strongly suggest that MMN is mediated by at least two separate neural systems, and that the frontal system matures earlier than the sensory-specific system.     

A comparative study of mismatch negativity (MMN) in epilepsy and non-epileptic seizures.

This study investigated mismatch negativity (MMN) differences between subjects with non-epileptic seizures (NES), subjects with epilepsy, and healthy controls. Event-related potentials (ERPs) were obtained from 14 patients with NES, 15 patients with epilepsy and 16 healthy control subjects. A conventional MMN procedure was used with a random sequence of 12% deviant tones (922 Hz) and 88% standard tones (1000 Hz). Subjects were instructed to ignore the tones delivered through headphones whilst reading a book. Significant differences in distribution of the mismatch negativity (MMN) in patients with NES compared to controls were obtained (F3, p 相似文献   

Nicotine and the hallucinating brain: effects on mismatch negativity (MMN) in schizophrenia

Elevated smoking rates have been noted in schizophrenia, and it has been hypothetically attributed to nicotine's ameliorating abnormal brain processes in this illness. There is some preliminary evidence that nicotine may alter pre-attentive auditory change detection, as indexed by the EEG-derived mismatch negativity (MMN), but no previous study has examined what role auditory verbal hallucinations (AVH) may have on these effects. The objective of this study was to examine MMN-indexed acoustic change detection in schizophrenia (SZ) following nicotine administration and elucidate its association with AVH. Using a modified multi-feature paradigm, MMNs to duration, frequency and intensity deviants were recorded in 12 schizophrenia outpatients (SZ) with persistent AVHs following nicotine (6mg) and placebo administration. Electrical activity was recorded from 32 scalp electrodes; MMN amplitudes and latencies for each deviant were compared between treatments and were correlated with trait (PSYRATS) and state measures of AVH severity and Positive and Negative Syndrome Scale (PANSS) ratings. Nicotine administration resulted in a shortened latency for intensity MMN. Additionally, nicotine-related change in MMN amplitude was correlated with nicotine-related change in subjective measures of hallucinatory state. In summary, nicotine did not affect MMN amplitudes in schizophrenia patients with persistent AVHs, however this study reports accelerated auditory change detection to intensity deviants with nicotine in this group. Additionally, nicotine appeared to induce a generalized activation of the auditory cortex in schizophrenia, resulting in a concurrent increase in intensity MMN amplitude and subjective clarity of AVHs.     

Review The relationship between the mismatch negativity (MMN) and psycholinguistic models of spoken word processing

Background: The results from previous studies have indicated that a pre‐attentive component of the event‐related potential (ERP), the mismatch negativity (MMN), may be an objective measure of the automatic auditory processing of phonemes and words. Aims: This article reviews the relationship between the MMN data and psycholinguistic models of spoken word processing, in order to determine whether the MMN may be used to objectively pinpoint spoken word processing deficits in individuals with aphasia. Main Contribution: This article outlines the ways in which the MMN data support psycholinguistic models currently used in the clinical management of aphasic individuals. Furthermore, the cell assembly model of the neurophysiological mechanisms underlying spoken word processing is discussed in relation to the MMN and psycholinguistic models. Conclusions: The MMN data support current theoretical psycholinguistic and neurophysiological models of spoken word processing. Future MMN studies that include normal and aphasic populations will further elucidate the role that the MMN may play in the clinical management of aphasic individuals.     

The use of conditional inference to reduce prediction error—A mismatch negativity (MMN) study

The brain uses regularities in the sound environment to build inference models predicting the most likely attributes of subsequent sounds. When the inference model fails, a prediction-error signal (the mismatch negativity or MMN) is generated. This study is designed to explore the capacity to use information about when a deviant sound will occur to switch between inference models in memory. We measured MMN generated to rare frequency, duration, intensity and spatial deviant sounds randomly occurring in a stream of identical repeating “standard” sounds. We then measured MMN to the same deviants in a linked sequence where deviants were paired—duration deviants followed an intensity change and spatial deviants followed a frequency change. To minimise prediction error, the brain should use the occurrence of the intensity and frequency deviant to prompt a change in the dominant inference (“expect-the-standard”) to anticipate the characteristics of the linked deviant. Anticipation was quantified as the proportion decline in duration and spatial MMN in the linked versus random sequence. We report three main outcomes on a sample of 23 healthy adults: (1) a significant reduction in duration MMN amplitude in linked versus random sequence; (2) a subgroup of participants exhibited significant reduction in spatial MMN amplitude in linked versus random sequence; and (3) the capacity to anticipate a linked deviant (reduce MMN) was a related to performance on the Continuous Performance Task-Identical Pairs. The results are discussed with respect to a possible co-reliance of CPT-IP and inference models on the inferior frontal gyrus.     

On the possibility of independent activation of bilateral mismatch negativity (MMN) generators.

Event-related potential (ERP) studies on auditory selective attention have suggested that the neuronal traces underlying the mismatch negativity (MMN) develop separately for left and right ear inputs. We investigated whether this feature of the MMN could be exploited to activate the MMN generators in each hemisphere independently. Given the location of the MMN sources, this would allow separate assessment of left and right hemisphere auditory cortical structures. The MMN was elicited in a dichotic oddball paradigm using stimuli and conditions of stimulation that should optimize transmission of left and right ear stimuli to the contralateral auditory cortices. The MMN demonstrated no interhemispheric asymmetries, indicating that the bilateral MMN generators were symmetrically involved. The results of a supplementary experiment provide evidence for the simultaneous existence of multiple traces for MMN generation.     

Reduced mismatch negativity (MMN) suggests deficits in pre-attentive auditory processing in distractible children

Mismatch negativity (MMN) event-related brain potential reflects the brain's automatic auditory change detection mechanism that depends on integrity of the auditory sensory memory. We studied MMN in easily distractible (n = 20) and in non-distractible (n = 20) healthy 9-year-old children. Two MMN phases were revealed in both groups: an earlier MMN peak at approximately 220 ms and a later negative slope approximately 300-500 ms after stimulus presentation. The results suggested a strong frontal lobe contribution in the generation of the later MMN phase, and this response was significantly reduced in amplitude in the distractible children. The present findings suggest that distractible children may have deficits in the frontally mediated aspects of auditory sensory memory.     

Distinct pre-attentive responses to non-scale notes: An auditory mismatch negativity (MMN) study

Objective: The aim of the present study was to examine patterns of neural activity in response to variations in scale notes and alterations from a scale note to a non-scale note.Methods: Event-related potentials (ERPs) were recorded in response to scale and non-scale violin notes using an odd-ball mismatch negativity (MMN) paradigm. Standard stimuli were set to the scale note A4 (440 Hz). Deviant stimuli included two scale notes (scale-B, B4 = 494 Hz; scale-C, C5 = 523 Hz) and a non-scale note halfway between them (non-scale, B4 + 42¢ = 506 Hz).Results: MMN amplitude elicited by the non-scale was significantly larger than that elicited by the scale-B and scale-C, which did not differ significantly from one another.Conclusion: The current results suggest that the human brain may possess pre-attentive mechanisms for extracting relational aspects among sounds of the musical scale.Significance: The results indicate that non-scale notes may be processed in a different way even in the pre-attentive stage than scale notes.     

The mismatch negativity (MMN) potential as a tool for the functional mapping of temporal lobe epilepsies

Temporal lobe epilepsies are associated with cognitive dysfunctions in memory which are important clues currently used clinically for the lateralization of the epileptic focus in evaluations for epilepsy surgery. Because these lobes also contain the primary auditory cortex, the study of auditory evoked potentials (AEPs) is a candidate, not yet established, complementary method to characterize epilepsy-induced dysfunction. We aimed to establish the clinical usefulness of auditory evoked potentials for the study of pediatric symptomatic temporal lobe epilepsies. A group of 17 patients (ages 4–16) with symptomatic epilepsies undergoing evaluation for epilepsy surgery epilepsy was submitted to auditory evoked potentials using 35-channel scalp EEG recordings. A control group of 10 healthy volunteers was studied with the same protocol. The P100 and mismatch negativity (MMN) potential latencies and normalized amplitudes were studied. We also performed a voxel-based lesion-symptom mapping (VLSM) to determine the anatomical areas associated with changes in the AEPs. Eleven patients had temporal lobe epilepsy, three had frontal lobe epilepsy, and three had occipital lobe epilepsy. Latencies for the P100 were normal in 15/17 and in 11/17 for the MMN, with no consistent correlation with the epilepsy type. The MMN amplitude was abnormal in 7/17 patients, all with temporal lobe epilepsies (sensitivity of 64%). Of these patients, four had a decreased MMN associated with a Heschl's gyrus lesion in the VLSM, and three had an increased MMN associated with hippocampal lesion. No extratemporal epilepsy showed MMN amplitude abnormalities (specificity of 100%). The P100 amplitude was abnormal in 3/17, two with temporal and one with frontal lobe epilepsies. The auditory MMN has a high specificity but a low sensitivity for temporal lobe epilepsy in symptomatic pediatric epilepsies. Amplitude decreases of the MMN are associated with homolateral Heschl's gyrus lesions, and MMN increases with hippocampal lesions.     

Alterations of mismatch negativity (MMN) in schizophrenia patients with auditory hallucinations experiencing acute exacerbation of illness

Auditory verbal hallucinations (AHs), or hearing 'voices', are one of the hallmark symptoms of patients with schizophrenia. The primary objective of this study was to compare hallucinating schizophrenia patients with respect to differences in deviance detection, as indexed by the auditory mismatch negativity (MMN). Patients were recruited during an acute psychotic episode requiring hospitalization, during which time symptoms of psychosis, including auditory hallucinations, are likely to be at their most severe. MMNs to duration, frequency, gap, intensity and location deviants (as elicited by the 'optimal' multi-feature paradigm) were recorded in 12 acutely ill schizophrenia patients (SZ) with persistent AHs and 15 matched healthy controls (HC). Electrical activity was recorded from 32 scalp electrodes. MMN amplitudes and latencies for each deviant were compared between groups and were correlated with trait (PSYRATS) and state measures of AH severity and Positive and Negative Syndrome Scale (PANSS) ratings in SZs. There were significant group differences for duration, gap, intensity and location MMN amplitudes, such that SZs exhibited reduced MMNs compared to HCs. Additionally, gap MMN amplitudes were correlated with measures of hallucinatory state and frequency of AHs, while location MMN was correlated with perceived location of AHs. In summary, this study corroborates previous research reporting a robust duration MMN deficit in schizophrenia, as well as reporting gap, intensity and location MMN deficits in acutely ill schizophrenia patients with persistent AHs. Additionally, MMN amplitudes were correlated with state and trait measures of AHs. These findings offer further support to previous work suggesting that the presence of auditory hallucinations may make a significant contribution to the widely reported MMN deficits in schizophrenia.     

Association between reduced duration mismatch negativity (MMN) and raised temporal discrimination thresholds in schizophrenia.

OBJECTIVE: The event-related potential known as mismatch negativity (MMN) is elicited whenever the auditory system detects a change against an invariant background of stimulation. A reduction in mismatch negativity is well established in schizophrenia. The present study explored the association between reduced duration mismatch negativity in schizophrenia and behavioural measures of temporal discrimination. METHOD: Mismatch negativity amplitude to duration increments (125 vs. 50 ms) was compared between individuals with schizophrenia and healthy controls. Mismatch negativity amplitude was also related to two behavioural measures of temporal discrimination (silent and filled intervals) for detecting changes in stimuli of similar duration. RESULTS: Patients produced higher discrimination threshold estimates and smaller amplitude mismatch negativity responses to temporally deviant stimuli. Temporal discrimination thresholds correlated with the amplitude of the phase reversal in mismatch negativity at the left mastoid such that patients who produced the highest thresholds produced the smallest mismatch response. CONCLUSIONS: Imprecise representations of the temporal properties of auditory stimuli can account for some of the reduction in mismatch negativity amplitude in some patients but additional factors clearly contribute. The results suggest that patients who do and do not exhibit temporal processing deficits on behavioural tasks produce different patterns of reduction in duration mismatch negativity.     

Effects of olanzapine on auditory P300 and mismatch negativity (MMN) in schizophrenia spectrum disorders

We investigated effects of olanzapine (5-10 mg/day) on passive and active attention in 11 patients with schizophrenia spectrum disorders and 15 healthy controls by using auditory evoked potentials (AEPs) mismatch negativity (MMN) and P300. AEPs were elicited during active and passive auditory "oddball" paradigms before, after 2 weeks and 4 weeks of olanzapine treatment. Baseline P300 amplitudes, but not MMN, were significantly reduced in patients compared with controls. Although clinical signs improved significantly measured by Positive and Negative Syndrome Scale (PANSS), olanzapine had no significant effects on latencies and amplitudes of MMN and P300. Thus, olanzapine does not have effects on active and passive attention in patients with schizophrenia spectrum disorders. Four weeks olanzapine treatment may be insufficient for the improvement of cognitive dysfunction in terms of inability to focus on relevant stimuli in these patients.     

Fast vigilance decrement in closed head injury patients as reflected by the mismatch negativity (MMN)

Event-related potentials (ERPs) were measured from 24 chronic closed head injury (CHI) patients and 18 age- and education-matched controls. The oddball paradigm was applied while subjects were watching a silent movie. The standard (p=0.8) sound of 75 ms duration had a basic frequency of 500 Hz with harmonic partials of 1000 Hz and 1500 Hz, whereas these frequencies for the pitch deviant were each 10% higher. The frequencies of the duration deviant matched with those of the standard but was 25 ms in duration. The MMN (mismatch negativity), generated by the brain's automatic auditory change-detector mechanism, was elicited by both deviants. No significant differences in the MMN latency or amplitude for either pitch or duration deviants were found between the groups. However, the MMN amplitude for the pitch deviant decreased in the patient group during the experiment considerably faster than in controls, suggesting a faster vigilance decrement in the patients.     

The mismatch negativity (MMN)--a unique window to disturbed central auditory processing in ageing and different clinical conditions

In this article, we review clinical research using the mismatch negativity (MMN), a change-detection response of the brain elicited even in the absence of attention or behavioural task. In these studies, the MMN was usually elicited by employing occasional frequency, duration or speech-sound changes in repetitive background stimulation while the patient was reading or watching videos. It was found that in a large number of different neuropsychiatric, neurological and neurodevelopmental disorders, as well as in normal ageing, the MMN amplitude was attenuated and peak latency prolonged. Besides indexing decreased discrimination accuracy, these effects may also reflect, depending on the specific stimulus paradigm used, decreased sensory-memory duration, abnormal perception or attention control or, most importantly, cognitive decline. In fact, MMN deficiency appears to index cognitive decline irrespective of the specific symptomatologies and aetiologies of the different disorders involved.     

Negative bias in expression-related mismatch negativity(MMN) in remitted late-life depression: An event-related potential study

Negative bias in cognition is closely associated with susceptibility to recurrent episodes of depression. Given the high recurrence rate of depression, previous studies have focused on the attentive level in late-life depression (LLD), but depression relapse is difficult to detect as a lower chief complaint in elderly people. Facial expression mismatch negativity (EMMN) is a tool that can measure cognitive bias in pre-attentive processing. In this study, we sought to explore the cognitive bias in pre-attentive emotional information processing in LLD. Thirty patients with remitted LLD and 30 non-depressed, age- and gender-matched normal controls (NC) were enrolled in this study. Automatic emotional processing was elicited by using an expression-related oddball paradigm in all participants. There were no significant differences in N170 amplitude and latency between remitted LLD and NC. Compared with NC subjects, patients with remitted LLD demonstrated an attenuated mean amplitude of positive and negative EMMN, whereas the mean amplitude of negative EMMN in remitted LLD was much larger than that of positive EMMN. Our findings suggest that although basic processing of facial expressions is intact in remitted LLD, automatic processing of facial expressions in remitted LLD is impaired with a negative bias in cognition. Further investigation of the contributions of negative bias in EMMN to susceptibility to recurrence of LLD is warranted.     

Measurement of extensive auditory discrimination profiles using the mismatch negativity (MMN) of the auditory event-related potential (ERP)

ObjectiveMismatch negativity (MMN), a change-specific component of the auditory event-related potential (ERP), is sensitive to deficits in central auditory processing associated with many clinical conditions. The aim of this study was to obtain a comprehensive multi-dimensional profile of central auditory processing by extending the recently developed fast multi-feature MMN paradigm [Näätänen R, Pakarinen S, Rinne T, Takegata R. The mismatch negativity (MMN): towards the optimal paradigm. Clin Neurophysiol 2004;115:140–144].MethodsMMN responses to changes in sound duration, frequency, intensity, and perceived sound-source location at six different magnitudes of deviation were recorded from healthy young adults by using the multi-feature MMN paradigm. In addition, behavioural discrimination accuracy and speed were measured to examine the relationship between MMN and behavioural performance.ResultsAll the 24 sound changes elicited significant MMNs. MMN amplitude increased and latency decreased with increasing magnitude of sound change. Furthermore, the MMN amplitude and latency predicted the subjects’ accuracy and speed in detecting these deviations.ConclusionsThis new paradigm provides an extensive auditory discrimination profile for several auditory attributes at different deviation magnitudes in a minimal recording time.SignificanceThe auditory discrimination profiles can offer a comprehensive view of the development, plasticity, and deficits of central auditory processing.     

Visual mismatch negativity: the detection of stimulus change

Mismatch negativity is an event related potential generated by a mechanism which detects stimulus change. Such a mechanism is important to enable attention to be switched to important changes in the environment. The effect has been extensively studied in the auditory modality. The present investigation was designed to establish whether the enhanced negativity in the visual event related potential evoked by deviant stimuli presented infrequently among a sequence of repeated standard stimuli is really associated with the detection of stimulus change. The experiment set out to distinguish effects associated with stimulus change from those related to the physical attributes of the stimuli or to differences in the refractory state of receptors or neurons. The findings support the hypothesis that deviance-related negativity reflects the operation of a change detection mechanism and not the refractory state of elements of the visual system.     

Electrophysiology of spatial scene analysis: the mismatch negativity (MMN) is sensitive to the ventriloquism illusion.

OBJECTIVES: The ventriloquism effect is the tendency to underestimate the spatial separation between synchronous auditory and visual signals moderately separated in space. If, as it is thought, this effect is pre-attentive, it could modulate the mismatch negativity (MMN) that indexes the automatic, pre-attentive detection of deviant auditory stimuli rarely occurring in a sequence of standard stimuli. We assessed the existence of an MMN evoked by auditory and visual signals made up of standard sounds coming from the same location as the visual signal and deviant sounds coming from lateral deviations (20 or 60 degrees). As first observed in a behavioral study, a ventriloquism effect occurred for 20 degrees spatial separation but not for 60 degrees. METHODS: Cortical evoked potentials were recorded using the oddball paradigm on 8 adults in auditory alone and audiovisual conditions. RESULTS: In the auditory alone condition, each spatial localization contrast elicited a significant MMN. In the audiovisual condition, a significant MMN was only evoked for the 60 degrees contrasts. CONCLUSIONS: The MMN evoked by spatial separation contrasts (20 and 60 degrees) in the auditory alone condition was suppressed by the corresponding audiovisual condition only when the latter yielded a ventriloquism effect, suggesting that this effect occurs at an early perceptual level.