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Background The systemic low-frequency oscillation (sLFO) functional (f)MRI signals extracted from the internal carotid artery (ICA) and the superior sagittal sinus (SSS) are found to have valuable physiological information. Purpose 1) To further develop and validate a method utilizing these signals to measure the delay times from the ICAs and the SSS. 2) To establish the delay time as an effective perfusion biomarker that associates with cerebral circulation time (CCT). 3) To explore within subject variations, and the effects of gender and age on the delay times. Study type Prospective. Subjects In all, 100 healthy adults (Human Connectome Project [HCP], age range 22-36 years, 54 females and 46 males), 56 healthy children (Adolescent Brain Cognitive Development project) were included. Field strength/sequence Echo planar imaging (EPI) sequence at 3T. Assessment The sLFO fMRI signals from the ICAs and the SSSs were extracted from the resting state fMRI data. The maximum cross-correlation coefficients and their corresponding delay times were calculated. The gender and age differences of delay times were assessed statistically. Statistical tests T-tests were conducted to measure the gender differences. The Kruskal-Wallis test was used to detect age differences. Results Consistent and robust results were found from 80% of the 400 HCP scans included. Negative correlations (-0.67) between the ICA and the SSS signals were found with the ICA signal leading the SSS signal by ∼5 sec. Within subject variation was 2.23 sec at the 5% significance level. The delay times were not significantly different between genders (P = 0.9846, P = 0.2288 for the left and right ICA, respectively). Significantly shorter delay times (4.3 sec) were found in the children than in the adults (P Data conclusion We have shown that meaningful perfusion information (ie, CCT) can be derived from the sLFO fMRI signals of the large blood vessels. Level of evidence 1 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;50:1504-1513.

The use of Multi-Voxel Pattern Analysis (MVPA) has increased considerably in recent functional magnetic resonance imaging studies. A crucial step consists in the choice of methods for the estimation of responses and their statistical significance. However, a systematic comparison of these and their adequacy to predominant experimental design is missing.In the current study, we compared three pattern estimation methods: Least-Squares Unitary (LSU), based on run-wise estimation, Least-Squares All (LSA) and Least-Squares Separate (LSS), which rely on trial-wise estimation. We compared the efficiency of these methods in an experiment where sustained activity had to be isolated from zero-duration events as well as in a block-design approach and in an event-related design. We evaluated the sensitivity of the t-test in comparison with two non-parametric methods based on permutation testing: one proposed in Stelzer et al. (2013), equivalent to performing a permutation in each voxel separately and the Threshold-Free Cluster Enhancement (Smith and Nichols, 2009).LSS resulted the most accurate approach to address the large overlap of signal among close events in the event-related designs. We found a larger sensitivity of Stelzer’s method in all settings, especially in the event-related designs, where voxels close to surpass the statistical threshold with the other approaches were now marked as informative regions.Our results provide evidence that LSS is the most accurate approach for unmixing events with different duration and large overlap of signal, consistent with previous studies showing better handling of collinearity in LSS. Moreover, Stelzer’s potentiates this better estimation with its larger sensitivity.

Objectives Our previous study showed that long-term practitioners of Sahaja Yoga Meditation (SYM) had around 7% larger grey matter volume (GMV) in the whole brain compared with healthy controls; however, when testing individual regions, only 5 small brain areas were statistically different between groups. Under the hypothesis that those results were statistically conservative, with the same dataset, we investigated in more detail the regional differences in GMV associated with the practice of SYM, with a different statistical approach. Design Twenty-three experienced practitioners of SYM and 23 healthy non-meditators matched on age, sex and education level, were scanned using structural magnetic resonance imaging (MRI). Their GMV were extracted and compared using Voxel-Based Morphometry (VBM). Using a novel ad-hoc general linear model, statistical comparisons were made to observe if the GMV differences between meditators and controls were statistically significant. Results In the 16 lobe area subdivisions, GMV was statistically significantly different in 4 out of 16 areas: in right hemispheric temporal and frontal lobes, left frontal lobe and brainstem. In the 116 AAL area subdivisions, GMV difference was statistically significant in 11 areas. The GMV differences were statistically more significant in right hemispheric brain areas. Conclusions The study shows that long-term practice of SYM is associated with larger GMV overall, and with significant differences mainly in temporal and frontal areas of the right hemisphere and the brainstem. These neuroplastic changes may reflect emotional and attentional control mechanisms developed with SYM. On the other hand, our statistical ad-hoc method shows that there were more brain areas with statistical significance compared to the traditional methodology which we think is susceptible to conservative Type II errors.

In this paper, we explore the utility of resting-state EEG measures as potential biomarkers for the detection and assessment of cognitive decline in mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Neurophysiological biomarkers of AD derived from EEG and FDG-PET, once characterized and validated, would expand the set of existing diagnostic molecular biomarkers of AD pathology with associated biomarkers of disease progression and neural dysfunction. Since symptoms of AD often begin to appear later in life, successful identification of EEG-based biomarkers must account for age-related neurophysiological changes that occur even in healthy individuals. To this end, we collected EEG data from individuals with AD (n = 26), MCI (n = 53), and cognitively normal healthy controls stratified by age into three groups: 18–40 (n = 129), 40–60 (n = 62) and 60–90 (= 55) years old. For each participant, we computed power spectral density at each channel and spectral coherence between pairs of channels. Compared to age matched controls, in the AD group, we found increases in both spectral power and coherence at the slower frequencies (Delta, Theta). A smaller but significant increase in power of slow frequencies was observed for the MCI group, localized to temporal areas. These effects on slow frequency spectral power opposed that of normal aging observed by a decrease in the power of slow frequencies in our control groups. The AD group showed a significant decrease in the spectral power and coherence in the Alpha band consistent with the same effect in normal aging. However, the MCI group did not show any significant change in the Alpha band. Overall, Theta to Alpha ratio (TAR) provided the largest and most significant differences between the AD group and controls. However, differences in the MCI group remained small and localized. We proposed a novel method to quantify these small differences between Theta and Alpha bands’ power using empirically derived distributions of spectral power across the time domain as opposed to averaging power across time. We defined Power Distribution Distance Measure (PDDM) as a distance measure between probability distribution functions (pdf) of Theta and Alpha power. Compared to average TAR, using PDDF enhanced the statistical significance, the effect size, and the spatial distribution of significant effects in the MCI group. We designed classifiers for differentiating individual MCI and AD participants from age-matched controls. The classification performance measured by the area under ROC curve after cross-validation were AUC = 0.85 and AUC = 0.6, for AD and MCI classifiers, respectively. Posterior probability of AD, TAR, and the proposed PDDM measure were all significantly correlated with MMSE score and neuropsychological tests in the AD group.

Background: Previous work designed a network-based protocol of cognitive training. This programme exploits a mechanism of induced task-oriented co-activation of multiple regions that are part of the default mode network (DMN), to induce functional rewiring and increased functional connectivity within this network. Objective: In this study, the programme was administered to patients with a diagnosis of mild cognitive impairment to test its effects in a clinical sample. Method: Twenty-three patients with mild cognitive impairment (mean age: 73.74 years, standard deviation 5.13, female/male ratio 13/10) allocated to the experimental condition, underwent one month of computerised training, while fourteen patients (mean age: 73.14 years, standard deviation 6.16, female/ male ratio 7/7) assigned to the control condition underwent a regime of intense social engagement. Patients were in the prodromal stage of Alzheimer's disease (AD) as confirmed by clinical follow ups for at least two years. The DMN was computed at baseline and retest, together with other, control patterns of connectivity, grey matter maps and neuropsychological profiles. Results: A condition-by-timepoint interaction indicating increased connectivity triggered by the programme was found in left parietal DMN regions. No decreases as well as no changes in the other networks or morphology were found. Although between-condition cognitive changes did not reach statistical significance, they correlated positively with changes in DMN connectivity in the left parietal region, supporting the hypothesis that parietal changes were beneficial. Conclusion: This programme of cognitive training up-regulates a pattern of connectivity which is pathologically down-regulated in AD. We argue that, when cognitive interventions are conceptualised as tools to induce co-activation repeatedly, they can lead to clinically relevant improvements in brain functioning, and can be of aid in support of pharmacological and other interventions in the earliest stages of AD.

Background: The noninjured, contralateral hemisphere is increasingly acknowledged in the process of recovery from acute ischemic stroke. We estimated the value of conventional electroencephalography (EEG) recordings for identifying contralateral hemisphere involvement in relation to functional recovery. Methods: We analyzed 2-min epochs from 21 electrode EEG registrations of 18 patients with acute hemispheric ischemic stroke and compared with 18 age-matched controls. Outcome was dichotomized as good (modified Rankin Scale [mRS] 0–2) or poor (mRS 3–5 or death) at 3 months. Effects of the infarct on the ipsi-and contralateral hemispheres were analyzed by the delta/alpha ratio (DAR) and 2 measures of functional connectivity (magnitude squared coherence [MSC] and weighted phase lag index [WPLI]). Results: DAR was higher in patients than in controls, both in the ipsilateral and in the contralateral hemisphere (median 4.5 ± 6.7 ipsilateral and 2.4 ± 2.0 contralateral vs. 0.5 ± 0.5 in the control group, p < 0.001), indicating robust EEG changes in both lesioned and non-lesioned hemisphere. MSC and WPLI in the alpha and beta frequency bands were lower in patients than in controls in both hemispheres, indicating clear disturbances of functional connectivity (p < 0.05). In the poor outcome group, contralateral MSC and WPLI were lower than in the good outcome group, although these differences did not reach statistical significance. Conclusions: Short conventional EEG measurements show robust changes of brain activity and functional connectivity in both ipsilateral and contralateral hemispheres of patients with acute ischemic stroke. Changes of remote functional connectivity tend to interact with functional recovery. Future studies should estimate predictive values for individual patients and interactions with plasticity enhancing treatments.

Purpose To compare white matter bundles and fiber tract changes in seizure-free and non-seizure-free idiopathic generalized epilepsy (IGE) patients. Method Forty adult patients with IGE underwent a 3 T brain MRI with DTI sequences. According to seizure control status, eighteen patients were classified as refractory (R) if they had presented at least one incapacitating seizure in the previous six months, while on appropriate antiepileptic drug treatment. Twenty two seizure-free patients with adequate seizure control were considered non-refractory (NR). We compared fractional anisotropy (FA) and mean diffusivity (MD) values in sixteen white matter tracts in the R and NR groups, and in twenty healthy subjects. Results R and NR groups did not differ in gender, age and education. We found decreased FA in two tracts in the R group (forceps major and right uncinate fasciculus) and approaching statistical significance in two tracts in the NR group (right cingulate gyrus and right uncinate fasciculus) group, as well as increased MD in six tracts in the R group (forceps minor, left thalamic anterior radiation, right inferior longitudinal fasciculus, right longitudinal superior parietal and temporal fasciculi, and right cingulate gyrus) and in five tracts in the NR group (forceps minor, left thalamic anterior radiation, right inferior longitudinal fasciculus, right longitudinal superior parietal and temporal fasciculi), compared to controls. No differences were noted comparing FA and MD values between R and NR groups. Conclusions In our patient population, refractory IGE patients on adequate antiepileptic drug treatment did not present more severe white matter tract involvement compared to non-refractory patients.

Background Transcranial MR-guided high-intensity focused ultrasound (tcMRgFUS) is a promising noninvasive method to treat medication-refractory essential tremor. Purpose/Hypothesis To define the correlation between lesion size after ablation, thermal dose, and clinical outcome in tcMRgFUS treatment of essential tremor. Study Type Retrospective. Population/Subjects/Phantom/Specimen/Animal Model Eight patients with medication-refractory essential tremor were treated using a tcMRgFUS system at 3T. Field Strength/Sequence T2-weighted images were acquired immediately and at 1 year posttreatment at 3T. Assessment An atlas of the thalamic nuclei and dose maps were warped to the posttreatment images. The thermal dose, the immediate posttreatment lesion volume and 1-year final lesion volume, and the volumes confined inside the ventral division of the ventral lateral posterior thalamic nucleus (VLpv) were correlated to clinical outcome at 1 month and 1 year using Pearson's coefficient. The spatial region of treatment correlating with maximal clinical outcome was derived in a normalized space from average maps of clinical tremor score improvement at 1 year. Statistical Tests Statistical significance was assessed using the Wilcoxon two-tailed rank test. Results The correlations between thermal dose, lesion volume posttreatment and at 1 year, and outcome at 1 year were good (r = 0.73, 0.65, 0.73, respectively), and were slightly better than at 1 month (r = 0.57, 0.49, 0.65). Reducing the measurement to include only the portion within the VLpv did not significantly modify the correlations (P = 0.09). The center of the spatial region of treatment was found in the anterior commissure – posterior commissure plane, 14.3 mm lateral from the midline, and 8.3 mm rostral to the posterior commissure. Data Conclusion In this pilot study a good correlation was found between the size of the lesion, the thermal dose, and the clinical outcome in patients treated for essential tremor with ablation of the VLpv with tcMRgFUS. Level of Evidence: 1 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2017.

This preliminary study aimed to evaluate whether there are changes in the apparent diffusion coefficient (ADC) values of the brain in patients presenting with Eisenmenger syndrome (ES).This cross-sectional study included 10 consecutively recruited patients with ES and 10 healthy control subjects. In the patients and controls, eight distinct neuroanatomical locations were selected for analysis. Quantitative measurements of ADC values of the frontal white matter (FWM), occipital white matter, lentiform nucleus (LN), thalamus, frontal cortex, anterior and posterior limbs of the internal capsule and caudate nucleus were measured. Statistical analysis was performed using SPSSThe ADC values of the FWM and LN were significantly higher in the ES group than that in the control group. The mean ADC levels of other brain regions were not significantly different between the groups.Chronic hypoxia in patients with ES may lead to diffusion changes in the brain tissue. There is a need for further studies to assess the clinical significance of cerebral ADC values in patients with ES. Advances in knowledge: The ratio of extracellular volume to intracellular volume in the FWM and LN can be considered to be increased in patients with ES.

Fifty healthy participants took part in a double-blind placebo-controlled study in which they were either given auditory alpha activity (8–12 Hz) training (N = 18), random beta training (N = 12), or no training at all (N = 20). A novel wireless electrode system was used for training without instructions, involving water-based electrodes mounted in an audio headset. Training was applied approximately at central electrodes. Post-training measurement using a conventional full-cap EEG system revealed a 10% increase in alpha activity at posterior sites compared to pre-training levels, when using the conventional index of alpha activity and a non-linear regression fit intended to model individual alpha frequency. This statistically significant increase was present only in the group that received the alpha training, and remained evident at a 3 month follow-up session, especially under eyes open conditions where an additional 10% increase was found. In an exit interview, approximately twice as many participants in the alpha training group (53%) mentioned that the training was relaxing, compared to those in either the beta (20%) or no training (21%) control groups. Behavioural measures of stress and relaxation were indicative of effects of alpha activity training but failed to reach statistical significance. These results are discussed in terms of a lack of statistical power. Overall, results suggest that self-guided alpha activity training using this novel system is feasible and represents a step forward in the ease of instrumental conditioning of brain rhythms.

Purpose To investigate whether elevated glucose metabolism in neurofibroma, determined by [F18]-FDG-PET, is correlated with cell density in MRI, as expressed through the apparent diffusion coefficient. Materials and methods Patients diagnosed with neurofibromatosis type 1 and peripheral nerve sheath tumors (PNST) were enrolled in this prospective, IRB-approved study. After a single [F18]-FDG injection, patients consecutively underwent [F18]-FDG-PET/CT and [F18]-FDG-PET/MRI on the same day. Maximum and mean standardized uptake values (SUVmax, SUVmean) on [F18]-FDG-PET/CT and [F18]-FDG-PET/MRI were compared, and correlated with minimum and mean apparent diffusion coefficients (ADCmean, ADCmin). Results A total of 12 (6 male/6 female, mean age was 16.2 ± 5.2 years) patients were prospectively included and analyzed on a per-lesion (n = 39) basis. The SUVmean of examined PNST showed a moderate negative correlation with the ADCmean (r = -.441) and ADCmin (r = -.477), which proved to be statistically significant (p = .005 and p = .002). The SUVmax of the respective lesions, however, showed a weaker negative correlation for ADCmean (r: -.311) and ADCmin (r: -.300) and did not reach statistical significance (p = .054 and p = .057). Lesion-based correlation between [F18]-FDG-PET/MRI and [F18]-FDG-PET/CT showed a moderate correlation for SUVmax (r = .353; p = .027) and a strong one for SUVmean (r = .879; p = .001)). Patient-based liver uptake (SUVmax and mean) of [F18]-FDG-PET/MRI and [F18]-FDG-PET/CT were strongly positively correlated (r = .827; p < .001 and r = .721; p < .001) but differed significantly (p < .001). Conclusions We found a statistically significant, negative correlation between glucose metabolism and cell density in PNST. Thus, ADCmean and ADCmin could possibly add complimentary information to the SUVmax and SUVmean and may serve as a potential determinant of malignant transformation of PNST.

In this work, the segmentation and analysis of the corpus callosum (CC) in autistic MR brain images is carried out using a fuzzy c-means (FCM)-based level set method. Initially, the images are skull-stripped using the geodesic active contour method. The CC is extracted from the skull-stripped images using the FCM-based level set method. FCM clustering forms the initial contour. The evolution of the curve is then regularized using a distance function in the level sets. The segmented CC is divided into five segments, whose areas are measured. The subjective results show that the proposed method is able to extract the CC from skull-stripped images. It is demonstrated that the level set with the FCM as the initial contour gives better results than those obtained with a manual initial contour. It is found that the autistic subjects have a reduced CC area compared to that of control subjects. The total CC area of autistic subjects gives a correlation of R = 0.39 with the verbal intelligence quotient (IQ) values. Further analysis shows that the anterior third region of the CC gives significant discrimination of the control and autistic subjects compared to the other segments. Its correlation (R) with verbal IQ is found to be 0.27 in autistic subjects. The feature area extracted from the CC and its segments are significant, hence the results may be clinically helpful in the mass screening of autistic subjects. � Taiwanese Society of Biomedical Engineering 2015.

BACKGROUND AND PURPOSE: Brain tumors affecting language-relevant areas may influence language lateralization. The purpose of this study was to systematically investigate language lateralization in brain tumor patients using clinical language fMRI, comparing the results with a group of healthy volunteers. MATERIALS AND METHODS: Fifty-seven strictly right-handed patients with left-hemispheric-space intracranial masses (mainly neoplastic) affecting either the Broca area ( n = 19) or Wernicke area ( n = 38) were prospectively enrolled in this study. Fourteen healthy volunteers served as a control group. Standardized clinical language fMRI, using visually triggered sentence- and word-generation paradigms, was performed on a 1.5T MR scanner. Semiautomated analyses of all functional data were conducted on an individual basis using BrainVoyager. A regional lateralization index was calculated for Broca and Wernicke areas separately versus their corresponding right-hemisphere homologs. RESULTS: In masses affecting the Broca area, a significant decrease in the lateralization index was found when performing word generation ( P = .0017), whereas when applying sentence generation, the decrease did not reach statistical significance ( P = .851). Masses affecting the Wernicke area induced a significant decrease of the lateralization index when performing sentence generation ( P = .0007), whereas when applying word generation, the decrease was not statistically significant ( P = .310). CONCLUSIONS: Clinical language fMRI was feasible for patients with brain tumors and provided relevant presurgical information by localizing essential language areas and determining language dominance. A significant effect of the brain masses on language lateralization was observed, with a shift toward the contralesional, nondominant hemisphere. This may reflect compensatory mechanisms of the brain to maintain communicative abilities.

Rationale Quantitative analysis of electroencephalographic signals (EEG) and their interpretation constitute a helpful tool in the assessment of the bioavailability of psychoactive drugs in the brain. Furthermore, psychotropic drug groups have typical signatures which relate biochemical mechanisms with specific EEG changes. Objectives To analyze the pharmacological effect of a dose of alprazolam on the connectivity of the brain during wakefulness by means of linear and nonlinear approaches. Methods EEG signals were recorded after alprazolam administration in a placebo-controlled crossover clinical trial. Nonlinear couplings assessed by means of corrected cross-conditional entropy were compared to linear couplings measured with the classical magnitude squared coherence. Results Linear variables evidenced a statistically significant drug-induced decrease, whereas nonlinear variables showed significant increases. All changes were highly correlated to drug plasma concentrations. The spatial distribution of the observed connectivity changes clearly differed from a previous study: changes before and after the maximum drug effect were mainly observed over the anterior half of the scalp. Additionally, a new variable with very low computational cost was defined to evaluate nonlinear coupling. This is particularly interesting when all pairs of EEG channels are assessed as in this study. Conclusions Results showed that alprazolam induced changes in terms of uncoupling between regions of the scalp, with opposite trends depending on the variables: decrease in linear ones and increase in nonlinear features. Maps provided consistent information about the way brain changed in terms of connectivity being definitely necessary to evaluate separately linear and nonlinear interactions.

Cerebral mapping of the spontaneous electroencephalographic activity was performed in 31 subjects suffering from migraine with aura and the results were compared with those of a matched control group. All the patients were examined during the interictal period. While traditional visual interpretation of EEG records was negative in all but five cases (16.1%) spectral analysis showed an asymmetry in alpha total power over the posterior regions in 13 cases (41.9%) and an asymmetry in alpha band peak frequency in 17 (54.8%). By means of cerebral mapping and statistical significance probability mapping we were able to demonstrate a significant increase in alpha total power in 13 cases (41.9%) and a regional increase in delta and theta total power in 20 cases (64.5%). In comparison with the control group, the migraine patients showed a widespread increase in slow activity (theta and delta) mostly over the temporal regions.

Alcoholism has been associated with lower density of striatal dopamine (DA) D2 receptors, but there is much less data on cortical DA D2 receptors. We evaluated the [125I]epidepride binding to DA D2 receptors in Cloninger type 1 and 2 alcoholics and controls in frontal, temporal, and anterior cingulate cortices by using human postmortem whole hemispheric autoradiography, which provides high-resolution images corresponding to positron emission tomographic (PET) studies. Type 1 alcoholics had lower and type 2 alcoholics had higher DA D2 receptor density in all cortical areas compared to controls. Although the results did not reach statistical significance, the effect sizes were high. The DA D2 receptor density in type 2 alcoholics decreased statistically significantly with age, and after correcting for age the binding values also fell below the level of controls. A statistically non-significant tendency towards a decrease of cortical DA D2 receptors was seen in controls, whereas in the type 1 alcoholic group no consistent correlation or even tendency towards increase with age was observed. Our results give preliminary evidence that DA D2 receptors in cortical areas may be lower among both groups of alcoholics, but not necessarily of same magnitude as in subcortical structures. The rapid decline of cortical DA D2 receptors among type 2 alcoholics may have some relevance to their antisociality, because this trait tends to diminish with age. The absence of correlation or even tendency towards increase of cortical DA D2 receptors with age seen in type 1 alcoholics may give further evidence that they have a pre-existing dopaminergic deficit. However, these results especially regarding aging effect must be considered as preliminary due to the different age-range of type 2 alcoholics compared to two other groups. Synapse 54:129–137, 2004. © 2004 Wiley-Liss, Inc.

Using magnetic resonance imaging and well-validated computational cortical pattern matching methods in a large and well-matched sample of healthy subjects, we analyzed the effects of gender on regional gray matter (GM) concentration across the cortex. To clarify discrepancies in previous reports, we also examined sexual dimorphisms for whole-brain tissue volumes with and without controlling for brain size differences. In addition, we generated spatially detailed maps of average GM distributions and variability across the entire cortex given that these descriptors are not well characterized in the normative literature. After brain size correction, we detected numerous cortical regions showing significantly increased GM concentration in females compared to males, but no regionally increased GM concentration in males. Permutation testing confirmed the statistical significance of these findings. Locally increased concentration of cortical GM in females corroborates findings of larger global GM volumes in females after correcting for individual brain sizes. Larger global volumes of GM, white matter and CSF, however, are observed in males when individual brain volumes are not taken into account. Our results show that gender is a major contributor to regional and global GM differences between individuals, although the nature of these effects depend on whether brain size is taken into account.

In a double-blind, placebo-controlled study on the therapeutic efficacy and central effects of nicergoline, an ergot alkaloid with metabolic, antithrombotic and vasoactive action, 112 patients with mild to moderate dementia, diagnosed according to DSM III-R criteria (MMS 13-25), living in pensioners' homes, were included. Fifty-six were subdiagnosed as senile dementia of the Alzheimer type (SDAT), 56 as multiinfarct dementia (MID), based on computed tomography and Hachinski scores (or = 49 SDAT,or = 7 MID). They received, after 2 weeks' run-in period (placebo), randomized for 8 weeks either 2 x 30 mg nicergoline (NIC) or 2 x 1 placebo (PLAC) orally. The four subgroups (SDAT/NIC. SDAT/PLAC, MID/NIC, MID/PLAC; 4 x 28 patients) were comparable in regard to age and sex. Only four, four, four and two patients of the respective groups did not finish the study for minor reasons. Confirmatory statistical analysis demonstrated in the target variable-the Clinical Global Impression (CGI)-a significant superiority of Global Impression (CGI)-a significant superiority of NIC over PLAC in both the SDAT and MID groups. Global improvement (CGI item 2) was seen in both nicergoline subgroups (3 and 3), while no changes occurred under placebo (4 and 4, respectively). The responder versus non-responder ratio was in the SDAT/NIC group 16/8, versus 8/16 in the SDAT/PLAC group (chi 2 = 4.1, P = 0.04); in the MID/NIC group 17/7, versus 7/19 in the MID/PLAC group (chi 2 = 7.96, P0.005). Furthermore, there was a significant improvement of the Mini-Mental State and the SCAG score in both the MID and SDAT group after 8 weeks of nicergoline, which was significantly superior to the minimal improvement or no change in placebo-treated SDAT and MID patients. EEG mapping demonstrated in NIC-treated SDAT and MID patients a significant decrease in delta and theta, increase in alpha 2 and beta activity and an acceleration of the centroid of the total power spectrum as compared with pretreatment, while opposite changes occurred in PLAC-treated SDAT and MID patients. The differences between PLAC and NIC reached the level of statistical significance. Event-related potential (ERP) recordings demonstrated a significantly shortened P300 latency under NIC treatment in both SDAT and MID patients, while there was a trend towards lengthening under PLAC. Thus, nicergoline improved vigilance and information processing at the neurophysiological level, which leads at the behavioural level to clinical improvement both in degenerative and vascular dementia.

Twenty Alzheimer's Disease (AD) patients in a mild to moderate stage of the disease and 20 control subjects were compared in 17 2-Hz wide bands from the electrodes 01, 02, P3, P4, T5, T6, F3, F4, F7, F8, Fpl, and Fp2. Differences reached statistical significance for 0–2 and 4–6 Hz bands, where AD patients presented highest power values. The AD group was divided into two groups according to the stage of disease. Both groups of patients presented 0–2 Hz increase in frontal, right parieto-temporal, and occipital areas. The increase in 4–6 Hz band was mainly over frontal areas in both groups and over left parietal region in moderate AD patients. These results and those relative to dominant frequency and crossover frequency between groups are discussed according to previous results with conventional and 2-Hz wide bands in AD patients in a severe stage of the disease.

SYNOPSIS Electroencephalographic (EEG) changes occurring in patients with migraine have received much attention. However, almost equal number of reports indicate the predominance of normal and abnormal findings. We studied the EEG in symptom-free, otherwise healthy, unmedicated 18–28 year-old patients: 22 with common migraine, 20 with classic migraine, and 20 age-matched controls. The routine EEG findings in the three groups revealed mild non-specific slowing in 2 (9%), 3 (15%) and 2 (10%), respectively. Simultaneously, topographic EEG mapping and frequency analysis were performed in 13 consecutive patients with common migraine, 10 patients with classic migraine and 11 age-matched controls. EEG mapping showed minimal regional differences with lower power in the alpha range in patients with eyes closed. The peak alpha power, as well as its reactivity, were lower among patients than controls. This difference reached statistical significance only for patients with classic migraine versus controls in the left occipital region. Patients also had slightly faster peak alpha frequency. No frank right-left asymmetry was observed in the peak alpha power, neither among the controls, nor the patients. All the findings were rather minor. They may suggest some difference in the posterior background activity in the EEG in migraine patients as compared to the controls, but are not useful in differentiating migraine from non-migraine patients.