title: Diagnostic and Predictive Value of Auditory Evoked Responses in Preterm Infants: II. Auditory Evoked Responses Attention and mismatch negativity. Auditory event-related potentials are related to cognition at preschool age after very preterm birth Neurophysiologic correlates of deficient phonological representations and object naming in prematurely born children Habituation as Parameter for Prediction of Mental Development in Healthy Preterm Infants Hemisphere Differences in Speech-Sound Event-Related Potentials in Intensive Care Neonates Maturational effects on newborn ERPs measured in the mismatch negativity paradigm
abstract: In this study , the diagnostic and predictive value of brainstem , middle latency , and cortical auditory evoked responses ( BMC -AERs ) obtained in the neonatal period in 81 preterm infants was assessed in relation to neurodevelopmental outcome .  The preterm infants were neonatally classified according to risk category and gestational age . The  BMC -AERs  were analyzed with respect to detectability , latencies , and amplitudes as well as derived latency and amplitude measures . At 5 y of age the neurodevelopmental outcome was assessed from neurologic and neuropsychologic evaluations . The results showed that BMC -AER differences mainly correlated with risk category ( low risk/high risk ) and to some extent with degree of prematurity . In view of these findings the degree of prematurity and the effect of risk category have to be taken into account , when BMC -AERs are applied in the preterm period to predict neurodevelopmental outcome . In this study the BMC -AERs for infants with abnormal neurodevelopmental outcome were scarcely distinguishable from the BMC -AERs for infants with normal neurodevelopmental outcome . Thus far , this and previous reports have indicated that BMC -AERs in preterm infants are useful in maturational studies and with infants showing symptoms related to lesions or dysfunction of the peripheral and /or central auditory system . For predicting neurodevelopmental outcome in preterm infants , BMC -AERs are of limited clinical value The mismatch negativity ( MMN ) component of the auditory event-related potential ( ERP ) is elicited by infrequent , physically deviant stimuli in a sequence of frequent homogeneous stimuli ( st and ards ) . It has been suggested that the MMN is generated by an automatic ( attention-independent ) neural mismatch process with a memory trace that encodes the physical features of the st and ard stimulus . The proposed MMN independence of attention was addressed in the present study . St and ard stimuli and two types of deviant stimuli , differing from st and ards either in frequency or intensity , were  dichotically  presented in r and om order and at a rapid rate . The subject attended either to left- or right-ear stimuli , counting the number of a design ated type of deviants in that ear . In the present conditions of very strongly focused attention , the MMN was elicited even by frequency change in the ignored input stream , and its amplitude was very similar to that of the MMN elicited by equivalent deviant stimuli ( targets ) in the attended input stream . In contrast , the MMN to intensity deviation was clearly attenuated in the absence of attention . This effect is , however , probably due to the attention effect on the MMN generator itself rather than the antecedent sensory- analysis and -storing functions Background : Auditory event-related potentials ( AERP ) are neurophysiological correlates of sound perception and cognitive processes . Our aim was to study in very preterm born children at preschool age if AERP correlate with cognitive outcome . Methods : Seventy children ( mean ± SD gestational age 27.4 ± 1.9 wk , birth weight 996 ± 288 g ) were investigated at age 4.3–5.3 y with psychological testing ( WPPSI-R , four subtests of NEPSY ) . Electroencephalogram was recorded while they listened to a repeated st and ard tone , r and omly replaced by one of three deviants .  Latencies and amplitudes for AERP components and mean amplitudes in successive 50-ms AERP time windows were measured . Results : Better cognitive test results and higher gestational age correlated with shorter P1 latencies and more positive mean amplitudes 150–500 ms after stimulus change onset . Neonatal brain damage was associated with a negative displacement of AERP curves . Neonatal morbidity had an impact on earlier time windows while gestational age and brain damage on both early and later time windows . Conclusion : AERP measures were associated with cognitive outcome . Neonatal morbidity mainly affects early cortical auditory encoding , while immaturity and brain damage additionally influence higher cortical functions of auditory perception and distraction . Perinatal auditory environment might play a role in development of auditory processing OBJECTIVE The aim of this follow-up study was to evaluate the development of object naming ability and auditory processing in prematurely born children . Furthermore , we investigated whether the mismatch negativity ( MMN ) parameters at the age of 4 years correlate with the MMN parameters and naming ability at the age of 6 years . METHODS Twelve very low birth weight ( VLBW ) preterm children ( mean age 5 years 7 months ) and matched controls were studied . Object naming was measured by the Boston naming test  . Auditory event-related potentials ( ERPs ) , especially the MMN  , were recorded for Finnish syllables ( st and ard /taa/ ; deviants /ta/ and /kaa/ ) in an oddball paradigm . RESULTS VLBW preterm children scored significantly lower in the object naming test than their controls . The MMN amplitude for consonant change was significantly smaller in the preterm group compared to the controls . The MMN amplitude at the age of 4 years correlated with the MMN amplitude at the age of 6 years . Furthermore , absence of the MMN at the age of 4 years predicted naming difficulties at the age of 6 years . CONCLUSIONS VLBW preterm children with a difficulty to preattentively discriminate changes in syllables , as indexed by the diminished change detection response , MMN , seem to have sustained naming difficulty . Therefore , it is reasonable to record the MMN along with the language development from infancy , in order to identify the children at risk for language deficiencies and to provide appropriate rehabilitation The aim of this prospect i ve pilot study was to evaluate the predictive value of discrimination and habituation , which was measured by mismatch negativity in 17 healthy very preterm ( mean gestational age 27.4 weeks ; range 25.0 - 31.3 ) and 16 term ( mean gestational age 40.3 weeks ; range 37.9 - 41.7 ) born infants at term equivalent age .  Developmental outcome was measured by Bayley Scales of Infant Development – I in 13 preterm and 13 term-born children at a mean age of 21.7 months ( ±2.18 ) and 18.5 months ( ±1.9 ) , respectively . No differences in amplitude and latency of the mismatch negativity were found between both groups at term equivalent age . Within the preterm group habituation capacity was positively correlated with the Mental Developmental Index ( r = .654 , P = .008 ) and Performance Developmental Index ( r = .482 , P = .048 ) at 21 months . Early learning capability , as measured by habituation , may be associated with a better prognosis for early mental development in healthy preterm infants Neurodevelopmental delays in intensive care neonates are common but difficult to predict . In children , hemisphere differences in cortical processing of speech are predictive of cognitive performance . We hypothesized that hemisphere differences in auditory event-related potentials in intensive care neonates are predictive of neurodevelopment in infancy , even in those born preterm .  Event-related potentials to speech sounds were prospect ively recorded in 57 infants ( gestational age 24 - 40 weeks ) prior to discharge . The Developmental Assessment of Young Children was performed at 6 and 12 months . Hemisphere differences in mean amplitudes increased with postnatal age ( P < .01 ) but not with gestational age . Greater hemisphere differences were associated with improved communication and cognitive scores at 6 and 12 months , but decreased in significance at 12 months after adjusting for socioeconomic and clinical factors . Auditory cortical responses can be used in intensive care neonates to help identify infants at higher risk for delays in infancy The mismatch negativity ( MMN ) component of event-related potentials ( ERPs ) , a measure of passive change detection , is suggested to develop early in comparison to other ERP components , and an MMN-like response has been measured even from preterm infants . The MMN response in adults is negative in polarity at about 150 - 200 ms . However , the response measured in a typical MMN paradigm can also be markedly different in newborns , even opposite in polarity . This has been suggested to be related to maturational factors . To verify that suggestion , we measured  ERPs  of 21 newborns during quiet sleep  to rarely occurring deviant tones of 1100 Hz ( probability 12 % ) embedded among repeated st and ard tones of 1000 Hz in an oddball sequence . Gestational age ( GA ) and two cardiac measures , vagal tone  ( V ) and  heart period ( HP ) , were used as measures of maturation . GA and HP explained between 36 % and 42 % of the total variance of the individual ERP peak amplitude ( the largest deflection of the difference wave at a time window of 150 - 375 ms ) at different scalp locations . In the discriminant function analyses , GA and HP as classifying variables differentiated infants in whom the peak of the difference wave had positive polarity from those with a negative polarity at an accuracy level ranging from 72 % to 91 % . These results demonstrate that during quiet sleep , maturational factors explain a significant portion of the ERP difference wave amplitude in terms of its polarity , indicating that the more mature the ERPs are , the more positive the amplitude . The present study suggests that maturational effects should be taken into account in ERP measurements using MMN paradigms with young infants
target: According to our findings , auditory event‐related potentials can help to predict neurodevelopmental outcome in preterms .
  Both prospect i ve and cross‐sectional studies reported a relationship between AERPs and cognitive outcome .
  Our results show that larger amplitudes and shorter latencies of late AERPs are related to better cognitive outcomes .
background: HIGHLIGHTSPreterm birth is associated with an elevated risk for neurodevelopmental deficits .
  Auditory event‐related potentials can be used to assess early cognitive functioning .
  This paper represents the first systematic review investigating the predictive power of AERPs on  cognition in preterms .
  ABSTRACT Prematurity is a known risk factor for later cognitive deficits .
  At present there are neither behavioral nor neurological tests available to detect those preterm infants who would benefit most from early interventions .
  Neurophysiologic methods , and more specifically , auditory event‐related potentials ( AERPs ) are convenient tools to investigate early cognitive functioning .
  However , the capability of AERPs as a prognostic factor for mental development in preterm infants remains unclear .