- Email: [email protected]
226. Neurofeedback effects on EEG and behavior in mild mentally retarded (MMR) children. Two months follow-up study
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Society Proceedings / Clinical Neurophysiology 119 (2008) e99–e164
deficit/ hyperactivity ADHD, recent event related potential (ERP) studies have shown functional impairments in cortical regions, specifically in early components, such as P1 or N1, both sensitive to selective attention effects. Our study aimed to test the lack of the modulation of the magnetic equivalent of the P1 by attention (higher intensity in brain activation during the attention task compared to the perceptive task) in ADHD children. We used magnetoencephalography (MEG) to measure event-related brain activity during a perceptive task and during a selective attention task in children with DSM-IV combined type ADHD (ADHDC) or predominantly inattentive type ADHD (ADHD-PI) and in age and intelligence-matched control children. Statistical comparison of control children and ADHD PI children indicated significant differences. The ”attentional effect” on the first visual evoked magnetic field component (100 ms) was detected by ANOVA in the control group (p = .010), while in the ADHD PI group it was not detected (p = .478). ADHD PI group showed a deficit in early visual selective attention processing. It has been proposed that during this stage stimuli are filtered out, so that, the absence of the attentional effect in ADHD PI could be related to the selective attention deficit in these children. doi:10.1016/j.clinph.2008.04.238
223. Otahara syndrome: Case review, in a 26-week preterm neonate—E. Olivas, L. Flores, H. Sarnat, J.M. Ibarra, B.A. ´ os (Mexico) Rı This study analyzed the clinical and electroencephalographic (EEG) characteristics of the Ohtahara syndrome in a 26-week preterm neonate. We completed the clinical case analysis through of the review of the clinical history and EEG recording and comparison with the literature. The ictal EEG during tonic spasm showed high voltage bursts of 400–800 ms, with voltage suppression phases varying from 200 ms to 2 s. The interictal EEG showed bursts of sharp wave, sharp and slow waves and polyspikes with slow waves of 200 ms–1 s, with voltage suppression of 3 a 97 s. The EEG characteristics observed in the preterm newborn with Ohtahara syndrome depend upon the degree of cerebral maturation, so that as maturation proceeds, the low voltage periods of suppression become briefer. We have analyzed the clinical EEG features of the Ohtahara syndrome in a preterm newborn. doi:10.1016/j.clinph.2008.04.239
224. Paroxysmal monorhytmic alpha activity in high risk ´ os infants—E. Olivas, D.S. Barreto, J. Ibarra, B Rı (Mexico) Paroxysmal monorhytmic alpha activity has been described in neonates with and without clinical seizure activity. We studied the electroencephalographic (EEG) characteristics of this rhythmic discharge, other EEG findings and the background activity. Besides, we study the clinical characteristics and neuroimaging findings. We developed a descriptive study. Data were obtained from medical records of neonates with this rhytmic discharge hospitalized at the Neonatal Intensive Care Unit and the Intermediate Care Unit at Instituto Nacional de Perinatologı´a during 2006.
Neonates (24) with paroxysmal monorhytmic alpha activity were identified. The amplitude of alpha trains was in order of 10– 300 lV, frequency 8–13 Hz, lasting 1–22 sec. localized to the frontal, temporal, central and occipital areas. 19 of 24 neonates also had others EEG abnormalities: surface-positive sharp waves, runs of spikes, polyspikes trains, trains of sharp and delta waves, delta waves discharges. 2 of 24 had suppression- burst pattern. All infants had background abnormalities. 2 of 24 had clinical seizure activity. Neuroimaging studies were abnormal in 17 infants: intraventricular haemorrhage, encephalomalacia, porencephaly, alobar holoprosencephaly. One infant died. Paroxysmal monorhytmic alpha activity is indicative of severe cerebral dysfunction. Paroxysmal monorhytmic activity in the alpha range is associated with severe brain damage. It can be used to predict neurodevelopment outcomes. doi:10.1016/j.clinph.2008.04.240
225. Differential cognitive pattern in patients with congenital Hypothyroidism according to etiology: Dyshormonogenesis and dysembriogenesis—A. Olivares Torres, C. Pe´rez Ge´sen, F. Carvajal Martı´nez, M. Pe´rez Avalo, L. Gala´n Garcı´a, ´ lvarez Gonza´lez (Cuba) A. A The purpose of this study was to evaluate and test whether brain event-related potentials (erps) are different in children with Congenital Hypothyroidism (CH) according to the etiology (Dysembriogenesis/ Dyshormonogenesis) after early high-dose levothyroxine treatment to confirm the double effect hypothesis in patients with HC. Visual erps were recorded in 14 normal controls and in 14 children with CH. The P300 component was measured and clinical variables were registered in these patients. Based on etiology, the CH group was divided in 2 subgroups: dysembriogenesis (n = 8) and dyshormonogenesis (n = 6). CH patients were treated at a median age of 20, 42 days with a mean initial dose of levothyroxine of 8.06 Ug/kg day. Study of the P300 component by analyzing the ERP measures revealed that there was no difference between CH subjects and controls, but it did differ between CH subjects of different etiologies. The P300 amplitude was significantly diminished in the dyshormonogenesis group as compared to the dysembriogenesis group. However, P300 latency was the same in CH and control groups, as well as in both etiologies. The cognitive pattern in dyshormonogenesis and dysembriogenesis etiologies has a similar behavior. We didn’t confirm the double effect hypothesis in the patients with HC. Erps can be used to find a differential cognitive pattern among patients with HC of different etiologies. doi:10.1016/j.clinph.2008.04.241
226. Neurofeedback effects on EEG and behavior in mild mentally retarded (MMR) children. Two months follow-up study—F. Garcı´a, T. Ferna´ndez, J. Becerra, M.I. Caballero, A. Ferna´ndez Bouzas, E. Santiago, H. Belmont, T. Harmony (Mexico) NFB is an operant conditioning procedure, whereby an individual can learn to modify the electrical activity of his or her
Society Proceedings / Clinical Neurophysiology 119 (2008) e99–e164
own brain. MMR children have an EEG slower than normal children of the same age. A NFB treatment was applied to 6 MMR children (IQ between 50 and 69), 6–11 years old (two boys) with normal neurological exam and abnormally higher theta/alpha ratio for their age. Positive reinforcement (tone of 500 Hz) was given when theta/alpha ratio was below a previously specified threshold. NFB training consisted of 30 sessions of 30 min each one. Significant changes in behaviour (IQ, Task of Attention Variables, and academic achievement) and EEG (reduction of theta Absolute Power and delta Relative Power, and increase of alpha and beta Relative Power) were observed. These changes were more apparent two months after NFB treatment. This NFB protocol is useful for the treatment of MMR children. This is the first report in MMR children using NFB.
e155
two evaluative poles (positive versus negative words) that appear on the screen. Both groups responded faster in a block where nonindigenous faces and positive words (as well as indigenous names and negative words) share a key, compared to the inverse block. The ANOVA and ERP analysis reveals an early N170 amplitude discrimination of other race and same raze stimuli (inverted for each group), simultaneously with and late positive potential (LPP) enhanced to in-group stimuli. We conclude that the present study support an early and late electrophysiological discrimination of conventional stereotypes of raze and valence. These results suggest simultaneously, the sensibility of N170 to raze feature, and a late (LPP) conscious evaluation of stimuli. doi:10.1016/j.clinph.2008.04.244
doi:10.1016/j.clinph.2008.04.242
229. An ERP study of category learning—A.J. Tabullo, A.A. Yorio, P. Pe´rez Leguizamon, E.T. Segura (Mexico) 227. Intrauterine drug exposure affects early auditory processing in newborn children—J.G. Martı´nez, A.A. Gonza´lez, F.R. Go´mez, A. Gutie´rrez Padilla (Mexico) In order to evaluate the early auditory processing in drugexposed children versus controls, by means of ERP techniques, we recorded the EEG during slow sleep was recorded in eight drug-exposed infants and eight healthy controls matched by sex, gestational age and corporal weight. Drug-exposed children had an averaged gestational age of 38.5 weeks, and age ranging from 3 to 30 days. Their averaged corporal weight was 2100 g and they all suffered an intrauterine exposure to a weekly averaged combined consumption of tobacco by mother – 20 mg of nicotine, cocaine 240 mg, and alcohol 80 mg, respectively. Event related brain potentials were obtained while presenting a stream of successive auditory tones–lasting 50 milliseconds–in an oddball paradigm (20/80), using 1000 Hz and 1300 Hz as infrequent and frequent stimuli, respectively. The inter-stimuli interval was 650 ms. A negative component peaking over 170 ms–a probable analogous of N100–was significantly higher in the drug-exposed infants. The effects of early drug exposure could affect the cortical recruiting of the neural resources involved in early auditory processing. ERP methods are valuable to early evaluate the effects of drugs on early auditory processing development. doi:10.1016/j.clinph.2008.04.243
Stimulus equivalence (Sidman, 1982, 1994) provides a model of category learning, and it has been argued that equivalence relations may be related to semantic processes. In the present study, we examined ERPs in a category learning task, comparing equivalence-related, identical and non-related stimulus. Ten healthy subjects participated on the experiment. A series of arbitrary relations between visual stimuli (A–B, B–C) were thought via matching to sample procedures. In the test phase, subjects were instructed to classify stimulus pairs as ‘‘equivalent” (C–A), ‘‘identical” or ‘‘non-related”. EEG activity was recorded during this phase. A frontocentral negativity was observed between 100 and 300 ms. The waveform elicited by identical stimuli was significantly less negative than the waveforms of equivalent and unrelated stimulus (F(2, 8) = 6.757, p = 0.019). A centroparietal negativity emerged between 350 and 600 ms. The waveform was significantly more positive for equivalent stimuli, and more negative for non-related stimuli (F(2, 8) = 7.322, p = 0.019). We argued that these waveforms correspond to a N200 component, associated with perceptual mismatch, and a N400 component, associated with semantic mismatch. N200 could reflect automatic attentional processes, and N400 could be a marker of categorization and decision taking. The observed ERPs can be considered as neural markers of perceptual and semantic categorization. The present findings support stimulus equivalence as a model of semantic processing. doi:10.1016/j.clinph.2008.04.245
228. N170 and LPP discrimination of same raze versus other raze facial stimuli and positive and negative words in indigenous and non-indigenous participants—R. Gonza´lez, V. Lo´pez, A. Haye, E. Hurtado, A. Navarro, A. Iban˜ez (Chile) This study assessed the ERPs modulation of racial face stimuli and negative versus positive words using the Implicit Association task in indigenous and non-indigenous participants. We record behavioral responses (RT) and electrophysiological correlates (ERPs, 128 channels, EGIs GES300 amplifier) of the Implicit Association Task (IAT) with indigenous (Mapuches) and nonindigenous Chileans participants. In the IAT, participants use two keys on the computer keyboard to categorize exemplars of two target categories (indigenous and non-indigenous faces) and
230. Habituation of visual event-related potentials in adults, healthy infants and infants with periventricular leukomalacia—B. Gonza´lez Frankenberger, T. Harmony, J. Ricardo Garcell, E. Porras Kattz, A. Ferna´ndez Bouzas, E. Santiago, ´ rez (Mexico) G. Avecilla Ramı The purpose of this study was to explore if habituation of evoked potentials to visual stimuli was present in adults, healthy infants and infants with periventricular leukomalacia (PVL) during sleep. Referential recordings to stimuli consisting of photic light stimulation presented by blocks were obtained. A total of 25 blocks each consisting of 15 stimuli were presented. Interblock
Society Proceedings / Clinical Neurophysiology 119 (2008) e99–e164
deficit/ hyperactivity ADHD, recent event related potential (ERP) studies have shown functional impairments in cortical regions, specifically in early components, such as P1 or N1, both sensitive to selective attention effects. Our study aimed to test the lack of the modulation of the magnetic equivalent of the P1 by attention (higher intensity in brain activation during the attention task compared to the perceptive task) in ADHD children. We used magnetoencephalography (MEG) to measure event-related brain activity during a perceptive task and during a selective attention task in children with DSM-IV combined type ADHD (ADHDC) or predominantly inattentive type ADHD (ADHD-PI) and in age and intelligence-matched control children. Statistical comparison of control children and ADHD PI children indicated significant differences. The ”attentional effect” on the first visual evoked magnetic field component (100 ms) was detected by ANOVA in the control group (p = .010), while in the ADHD PI group it was not detected (p = .478). ADHD PI group showed a deficit in early visual selective attention processing. It has been proposed that during this stage stimuli are filtered out, so that, the absence of the attentional effect in ADHD PI could be related to the selective attention deficit in these children. doi:10.1016/j.clinph.2008.04.238
223. Otahara syndrome: Case review, in a 26-week preterm neonate—E. Olivas, L. Flores, H. Sarnat, J.M. Ibarra, B.A. ´ os (Mexico) Rı This study analyzed the clinical and electroencephalographic (EEG) characteristics of the Ohtahara syndrome in a 26-week preterm neonate. We completed the clinical case analysis through of the review of the clinical history and EEG recording and comparison with the literature. The ictal EEG during tonic spasm showed high voltage bursts of 400–800 ms, with voltage suppression phases varying from 200 ms to 2 s. The interictal EEG showed bursts of sharp wave, sharp and slow waves and polyspikes with slow waves of 200 ms–1 s, with voltage suppression of 3 a 97 s. The EEG characteristics observed in the preterm newborn with Ohtahara syndrome depend upon the degree of cerebral maturation, so that as maturation proceeds, the low voltage periods of suppression become briefer. We have analyzed the clinical EEG features of the Ohtahara syndrome in a preterm newborn. doi:10.1016/j.clinph.2008.04.239
224. Paroxysmal monorhytmic alpha activity in high risk ´ os infants—E. Olivas, D.S. Barreto, J. Ibarra, B Rı (Mexico) Paroxysmal monorhytmic alpha activity has been described in neonates with and without clinical seizure activity. We studied the electroencephalographic (EEG) characteristics of this rhythmic discharge, other EEG findings and the background activity. Besides, we study the clinical characteristics and neuroimaging findings. We developed a descriptive study. Data were obtained from medical records of neonates with this rhytmic discharge hospitalized at the Neonatal Intensive Care Unit and the Intermediate Care Unit at Instituto Nacional de Perinatologı´a during 2006.
Neonates (24) with paroxysmal monorhytmic alpha activity were identified. The amplitude of alpha trains was in order of 10– 300 lV, frequency 8–13 Hz, lasting 1–22 sec. localized to the frontal, temporal, central and occipital areas. 19 of 24 neonates also had others EEG abnormalities: surface-positive sharp waves, runs of spikes, polyspikes trains, trains of sharp and delta waves, delta waves discharges. 2 of 24 had suppression- burst pattern. All infants had background abnormalities. 2 of 24 had clinical seizure activity. Neuroimaging studies were abnormal in 17 infants: intraventricular haemorrhage, encephalomalacia, porencephaly, alobar holoprosencephaly. One infant died. Paroxysmal monorhytmic alpha activity is indicative of severe cerebral dysfunction. Paroxysmal monorhytmic activity in the alpha range is associated with severe brain damage. It can be used to predict neurodevelopment outcomes. doi:10.1016/j.clinph.2008.04.240
225. Differential cognitive pattern in patients with congenital Hypothyroidism according to etiology: Dyshormonogenesis and dysembriogenesis—A. Olivares Torres, C. Pe´rez Ge´sen, F. Carvajal Martı´nez, M. Pe´rez Avalo, L. Gala´n Garcı´a, ´ lvarez Gonza´lez (Cuba) A. A The purpose of this study was to evaluate and test whether brain event-related potentials (erps) are different in children with Congenital Hypothyroidism (CH) according to the etiology (Dysembriogenesis/ Dyshormonogenesis) after early high-dose levothyroxine treatment to confirm the double effect hypothesis in patients with HC. Visual erps were recorded in 14 normal controls and in 14 children with CH. The P300 component was measured and clinical variables were registered in these patients. Based on etiology, the CH group was divided in 2 subgroups: dysembriogenesis (n = 8) and dyshormonogenesis (n = 6). CH patients were treated at a median age of 20, 42 days with a mean initial dose of levothyroxine of 8.06 Ug/kg day. Study of the P300 component by analyzing the ERP measures revealed that there was no difference between CH subjects and controls, but it did differ between CH subjects of different etiologies. The P300 amplitude was significantly diminished in the dyshormonogenesis group as compared to the dysembriogenesis group. However, P300 latency was the same in CH and control groups, as well as in both etiologies. The cognitive pattern in dyshormonogenesis and dysembriogenesis etiologies has a similar behavior. We didn’t confirm the double effect hypothesis in the patients with HC. Erps can be used to find a differential cognitive pattern among patients with HC of different etiologies. doi:10.1016/j.clinph.2008.04.241
226. Neurofeedback effects on EEG and behavior in mild mentally retarded (MMR) children. Two months follow-up study—F. Garcı´a, T. Ferna´ndez, J. Becerra, M.I. Caballero, A. Ferna´ndez Bouzas, E. Santiago, H. Belmont, T. Harmony (Mexico) NFB is an operant conditioning procedure, whereby an individual can learn to modify the electrical activity of his or her
Society Proceedings / Clinical Neurophysiology 119 (2008) e99–e164
own brain. MMR children have an EEG slower than normal children of the same age. A NFB treatment was applied to 6 MMR children (IQ between 50 and 69), 6–11 years old (two boys) with normal neurological exam and abnormally higher theta/alpha ratio for their age. Positive reinforcement (tone of 500 Hz) was given when theta/alpha ratio was below a previously specified threshold. NFB training consisted of 30 sessions of 30 min each one. Significant changes in behaviour (IQ, Task of Attention Variables, and academic achievement) and EEG (reduction of theta Absolute Power and delta Relative Power, and increase of alpha and beta Relative Power) were observed. These changes were more apparent two months after NFB treatment. This NFB protocol is useful for the treatment of MMR children. This is the first report in MMR children using NFB.
e155
two evaluative poles (positive versus negative words) that appear on the screen. Both groups responded faster in a block where nonindigenous faces and positive words (as well as indigenous names and negative words) share a key, compared to the inverse block. The ANOVA and ERP analysis reveals an early N170 amplitude discrimination of other race and same raze stimuli (inverted for each group), simultaneously with and late positive potential (LPP) enhanced to in-group stimuli. We conclude that the present study support an early and late electrophysiological discrimination of conventional stereotypes of raze and valence. These results suggest simultaneously, the sensibility of N170 to raze feature, and a late (LPP) conscious evaluation of stimuli. doi:10.1016/j.clinph.2008.04.244
doi:10.1016/j.clinph.2008.04.242
229. An ERP study of category learning—A.J. Tabullo, A.A. Yorio, P. Pe´rez Leguizamon, E.T. Segura (Mexico) 227. Intrauterine drug exposure affects early auditory processing in newborn children—J.G. Martı´nez, A.A. Gonza´lez, F.R. Go´mez, A. Gutie´rrez Padilla (Mexico) In order to evaluate the early auditory processing in drugexposed children versus controls, by means of ERP techniques, we recorded the EEG during slow sleep was recorded in eight drug-exposed infants and eight healthy controls matched by sex, gestational age and corporal weight. Drug-exposed children had an averaged gestational age of 38.5 weeks, and age ranging from 3 to 30 days. Their averaged corporal weight was 2100 g and they all suffered an intrauterine exposure to a weekly averaged combined consumption of tobacco by mother – 20 mg of nicotine, cocaine 240 mg, and alcohol 80 mg, respectively. Event related brain potentials were obtained while presenting a stream of successive auditory tones–lasting 50 milliseconds–in an oddball paradigm (20/80), using 1000 Hz and 1300 Hz as infrequent and frequent stimuli, respectively. The inter-stimuli interval was 650 ms. A negative component peaking over 170 ms–a probable analogous of N100–was significantly higher in the drug-exposed infants. The effects of early drug exposure could affect the cortical recruiting of the neural resources involved in early auditory processing. ERP methods are valuable to early evaluate the effects of drugs on early auditory processing development. doi:10.1016/j.clinph.2008.04.243
Stimulus equivalence (Sidman, 1982, 1994) provides a model of category learning, and it has been argued that equivalence relations may be related to semantic processes. In the present study, we examined ERPs in a category learning task, comparing equivalence-related, identical and non-related stimulus. Ten healthy subjects participated on the experiment. A series of arbitrary relations between visual stimuli (A–B, B–C) were thought via matching to sample procedures. In the test phase, subjects were instructed to classify stimulus pairs as ‘‘equivalent” (C–A), ‘‘identical” or ‘‘non-related”. EEG activity was recorded during this phase. A frontocentral negativity was observed between 100 and 300 ms. The waveform elicited by identical stimuli was significantly less negative than the waveforms of equivalent and unrelated stimulus (F(2, 8) = 6.757, p = 0.019). A centroparietal negativity emerged between 350 and 600 ms. The waveform was significantly more positive for equivalent stimuli, and more negative for non-related stimuli (F(2, 8) = 7.322, p = 0.019). We argued that these waveforms correspond to a N200 component, associated with perceptual mismatch, and a N400 component, associated with semantic mismatch. N200 could reflect automatic attentional processes, and N400 could be a marker of categorization and decision taking. The observed ERPs can be considered as neural markers of perceptual and semantic categorization. The present findings support stimulus equivalence as a model of semantic processing. doi:10.1016/j.clinph.2008.04.245
228. N170 and LPP discrimination of same raze versus other raze facial stimuli and positive and negative words in indigenous and non-indigenous participants—R. Gonza´lez, V. Lo´pez, A. Haye, E. Hurtado, A. Navarro, A. Iban˜ez (Chile) This study assessed the ERPs modulation of racial face stimuli and negative versus positive words using the Implicit Association task in indigenous and non-indigenous participants. We record behavioral responses (RT) and electrophysiological correlates (ERPs, 128 channels, EGIs GES300 amplifier) of the Implicit Association Task (IAT) with indigenous (Mapuches) and nonindigenous Chileans participants. In the IAT, participants use two keys on the computer keyboard to categorize exemplars of two target categories (indigenous and non-indigenous faces) and
230. Habituation of visual event-related potentials in adults, healthy infants and infants with periventricular leukomalacia—B. Gonza´lez Frankenberger, T. Harmony, J. Ricardo Garcell, E. Porras Kattz, A. Ferna´ndez Bouzas, E. Santiago, ´ rez (Mexico) G. Avecilla Ramı The purpose of this study was to explore if habituation of evoked potentials to visual stimuli was present in adults, healthy infants and infants with periventricular leukomalacia (PVL) during sleep. Referential recordings to stimuli consisting of photic light stimulation presented by blocks were obtained. A total of 25 blocks each consisting of 15 stimuli were presented. Interblock