Influence of propofol on the electroencephalogram default mode network in patients of advanced age.

OBJECTIVE: This study was performed to evaluate the effects of propofol on the electroencephalogram (EEG) default mode network (DMN) in patients of advanced age. METHODS: Fifteen men aged >60 years (mean, 70 years) were selected. Propofol target-controlled infusion was performed under EEG bispectral index monitoring. The propofol target effect-site concentration, blood pressure, heart rate, and distributions and powers of the EEG spectrum were recorded in an awake state and under anesthesia. The EEG included seven bands: delta (0.5-3.5 Hz), theta (4.0-7.0 Hz), alpha-1 (7.5-9.5 Hz), alpha-2 (10-12 Hz), beta-1 (13-23 Hz), beta-2 (24-34 Hz), and gamma (35-45 Hz). RESULTS: From an awake state to anesthesia, the brain topographic map showed that the energies of delta, theta, alpha-1, alpha-2, and beta-1 were concentrated in the frontoparietal site, and the power increased significantly. The energy distribution of beta-2 was significantly decreased and the power significantly reduced. The energy distribution of gamma in the temporal lobe was also markedly decreased and the power significantly reduced. CONCLUSIONS: This study revealed the changes in the spatial distribution and regional energy of the EEG DMD in men of advanced age from the awake state to the anesthetized state.

Review on Neural Correlates of Emotion Regulation and Music: Implications for Emotion Dysregulation.

Previous studies have examined the neural correlates of emotion regulation and the neural changes that are evoked by music exposure. However, the link between music and emotion regulation is poorly understood. The objectives of this review are to (1) synthesize what is known about the neural correlates of emotion regulation and music-evoked emotions, and (2) consider the possibility of therapeutic effects of music on emotion dysregulation. Music-evoked emotions can modulate activities in both cortical and subcortical systems, and across cortical-subcortical networks. Functions within these networks are integral to generation and regulation of emotions. Since dysfunction in these networks are observed in numerous psychiatric disorders, a better understanding of neural correlates of music exposure may lead to more systematic and effective use of music therapy in emotion dysregulation.

Intact skull chronic windows for mesoscopic wide-field imaging in awake mice.

BACKGROUND: Craniotomy-based window implants are commonly used for microscopic imaging, in head-fixed rodents, however their field of view is typically small and incompatible with mesoscopic functional mapping of cortex. NEW METHOD: We describe a reproducible and simple procedure for chronic through-bone wide-field imaging in awake head-fixed mice providing stable optical access for chronic imaging over large areas of the cortex for months. RESULTS: The preparation is produced by applying clear-drying dental cement to the intact mouse skull, followed by a glass coverslip to create a partially transparent imaging surface. Surgery time takes about 30min. A single set-screw provides a stable means of attachment (in relation to the measured lateral and axial resolution) for mesoscale assessment without obscuring the cortical field of view. COMPARISON WITH EXISTING METHODS: We demonstrate the utility of this method by showing seed-pixel functional connectivity maps generated from spontaneous cortical activity of GCAMP6 signals in both awake and anesthetized mice in longitudinal studies of up to 2 months in duration. CONCLUSIONS: We propose that the intact skull preparation described here may be used for most longitudinal studies that do not require micron scale resolution and where cortical neural or vascular signals are recorded with intrinsic sensors or in transgenic mice expressing genetically encoded sensors of activity.

Delayed finger tapping and cognitive responses in preterm-born male teenagers with mild spastic diplegia.

BACKGROUND: Information on fine motor and basic cognitive functions in spastic diplegia is sparse in the literature. The aim of this study was to investigate index finger's tapping speed and cognitive functions in categorization and old/new recognition of pictures in patients with mild spastic diplegia. METHODS: Fifteen preterm-born male teenagers with mild spastic diplegia and 15 healthy male teenagers participated in this study. Finger-tapping tests and cognitive tests were performed on all participants. Outcomes were compared between the two groups. RESULTS: In the finger-tapping tests, the tapping speed was significantly slower in patients than in controls. In the tests of tapping one key persistently and tapping two keys alternately, the reaction time gaps between the left and right digits were larger in patients than in controls. In the categorization tests, the accuracies and reaction times for animal/plant and girl face pictures, but not for boy face pictures, were significantly worse in patients than in controls. In the recognition tests, the accuracies for old/new, animal/plant, and boy/girl face pictures were significantly lower in patients than in controls. The reaction times for old/new, animal/plant, and new face pictures, but not for old face pictures, were significantly longer in patients compared with controls. CONCLUSIONS: Our results demonstrate delayed finger tapping and cognitive responses in preterm-born male teenagers with mild spastic diplegia. Our experimental paradigm is sensitive for the study of fine motor and cognitive functions between patients and healthy controls.

Neurochemical correlates of cognitive dysfunction in patients with leukoaraiosis: a proton magnetic resonance spectroscopy study.

OBJECTIVES: Leukoaraiosis (LA) is a common radiological finding in the elderly and may reflect cerebral small vessel disease (SVD). Although SVD has been identified as a major cause of vascular cognitive impairment or vascular dementia, the mechanisms for this association remain unclear. We therefore aimed to measure brain metabolites in LA using proton magnetic resonance spectroscopy ((1)H-MRS) as to determine the relationship between cognitive function and neurochemical white matter profile. METHODS: We recruited 23 patients with LA and 23 age- and sex-matched healthy controls consecutively. Multi-voxel (1)H-MRS was performed with a volume of interest located in centrum semiovale that contained mainly white matter voxels. Three main ratios of N-acetyl aspartate (NAA)/Cr, choline (Cho)/Cr and NAA/Cho were obtained. Spearman rank correlation coefficients were calculated between the cognitive function and the measured metabolite ratios. RESULTS: We found significantly lower levels of NAA/Cho and NAA/Cr ratios in lesioned white matter in patients with LA than healthy controls (P<0.05). The ratios of NAA/Cho and NAA/Cr in normal appearing white matter (NAWM) were higher than lesioned white matter and lower than controls, but this difference was not significant (P>0.05). There was a positive relationship between Mini-Mental State Examination (MMSE) and NAA/Cho in NAWM (r = 0.417, P = 0.048), and also a positive relationship between MMSE and NAA/Cr in lesioned white matter (r = 0.551, P = 0.006) in patients with LA. A positive relationship between the Z scores of the executive function and NAA/Cho in lesioned white matter (r = 0.557, P = 0.006) was also found. CONCLUSION: The main finding of this study was a significant reduction in the ratios of NAA/Cr and NAA/Cho in lesioned white matter, which indicates a marker of neuronal loss or dysfunction in patients with LA, which was correlated with cognitive function. This relationship between cognitive function and metabolic changes suggests that (1)H-MRS can be explored as a marker for cognitive dysfunction in patients with LA.

Replication and extension of the simplified modified rankin scale in 150 Chinese stroke patients.

BACKGROUND: Recently, a simplified modified Rankin Scale (mRS) questionnaire (smRSq) showed good reliability but has not been tested for its validity by its original creators. Our study aimed to test its reliability and validity in Chinese stroke patients. METHODS: Randomly chosen paired raters scored the smRSq, the conventional mRS, and the NIH Stroke Scale (NIHSS) face-to-face in 150 hospitalized stroke patients. Inter-rater reliability and concurrent validity were assessed for this translated questionnaire. RESULTS: For inter-rater reliability of the smRSq, the overall agreement among the raters was 84%, the κ was 0.79 (95% CI 0.72-0.87), and the κw was 0.91 (95% CI 0.88-0.94). For inter-rater reliability of the mRS, the overall agreement among the raters was 81%, the κ was 0.75 (95% CI 0.67-0.83), and the κw was 0.88 (95% CI 0.84-0.92). The agreement between the mRS and smRSq was 71%, κ = 0.63 (95% CI 0.54-0.71), and κw = 0.83 (95% CI 0.79-0.88). The correlation between the NIHSS and the smRSq (concurrent validity) was moderate (Spearman's correlation coefficient 0.70, p < 0.0001). CONCLUSIONS: Our results confirm the value of the smRSq in the assessment of stroke functional outcome in China. As this is a novel stroke tool, further validations are needed.

Sensory handedness is not reflected in cortical responses after basic nerve stimulation: a MEG study.

Motor dominance is well established, but sensory dominance is much less clear. We therefore studied the cortical evoked magnetic fields using magnetoencephalography (MEG) in a group of 20 healthy right handed subjects in order to examine whether standard electrical stimulation of the median and ulnar nerve demonstrated sensory lateralization. The global field power (GFP) curves, as an indication of cortical activation, did not depict sensory lateralization to the dominant left hemisphere. Comparison of the M20, M30, and M70 peak latencies and GFP values exhibited no statistical differences between the hemispheres, indicating no sensory hemispherical dominance at these latencies for each nerve. Field maps at these latencies presented a first and second polarity reversal for both median and ulnar stimulation. Spatial dipole position parameters did not reveal statistical left-right differences at the M20, M30 and M70 peaks for both nerves. Neither did the dipolar strengths at M20, M30 and M70 show a statistical left-right difference for both nerves. Finally, the Laterality Indices of the M20, M30 and M70 strengths did not indicate complete lateralization to one of the hemispheres. After electrical median and ulnar nerve stimulation no evidence was found for sensory hand dominance in brain responses of either hand, as measured by MEG. The results can provide a new assessment of patients with sensory dysfunctions or perceptual distortion when sensory dominance occurs way beyond the estimated norm.

The impact of a regular blood donation on the hematology and EEG of healthy young male blood donors.

The aim of this study was to investigate the effect of 400 ml whole blood donation on the human electroencephalogram (EEG) and hematology, not earlier reported in the literature. EEG activity was recorded from ten male blood donors (experiment group) before, during and after blood donation (i.e., 400 ml whole blood withdrawal). EEG topography and regional spectral field powers analyses were carried out via fast Fourier transformation. The venous hemoglobin (Hb) concentration was measured with a hematology analyzer. In the control investigation, 12 male age-matched volunteers (control group) were kept in semi-sitting position for the duration of a blood donation without actually vena puncture. The volunteers had no prior experiences of blood donation. Within the experiment group, post-donation Hb concentration decreased by 3.7% compared with the pre-donation Hb values (P < 0.01). Before blood donation, Hb concentration in control group was significantly higher compared to the experiment group (P < 0.05). For the experiment group, the field power of alpha-1 (7.5-9.5 Hz) EEG during blood withdrawal was significantly lower compared to that after blood withdrawal (P < 0.05). In contrast for the control group, all seven bands of regional spectral field powers showed no significantly discrepancies in the three periods. Blood donation attenuates the alpha-1 at the parietal-frontal area on human EEG-DMN transiently with no lasting effect at post-donation period. The blood donation-related effects on brain function may be of little consequence due to slight hemodynamic change and the results may facilitate the opinion that blood donation is a safe process and that should not discourage volunteers.

Anesthetic block of pain-related cortical activity in patients with peripheral nerve injury measured by magnetoencephalography.

BACKGROUND: This study examined whether chronic neuropathic pain, modulated by a local anesthetic block, is associated with cortical magnetic field changes. METHODS: In a group of 20 patients with pain caused by unilateral traumatic peripheral nerve injury, a local block with lidocaine 1% was administered and the cortical effects were measured and compared with a control group. The global field power (GFP), describing distribution of cortical activation after median and ulnar nerve stimulation, was plotted and calculated. The effects on the affected hemisphere and the unaffected hemisphere (UH) before and after a block of the injured nerve were statistically evaluated. RESULTS: Major differences based on the GFP curves, at a component between 50 ms - 90 ms (M70), were found in patients: in the affected hemisphere the M70 GFP peak values were statistically significantly larger in comparison with the UH, and the GFP curves differed morphologically. Interestingly, the mean UH responses were reduced in comparison with the control group, a finding suggesting that the UH is also part of the cortical changes. At M70, the GFP curves and values in the affected hemisphere were modulated by a local block of the median or the ulnar nerve. The most likely location of cortical adaptation is in the primary somatosensory cortex. CONCLUSIONS: Cortical activation is enhanced in the affected hemisphere compared with the UH and is modulated by a local block. The UH in neuropathic pain changes as well. Evoked fields may offer an opportunity to monitor the effectiveness of treatments of neuropathic pain in humans.

Effect of homobaric pure oxygen on sensory gating in the human brain.

Sensory gating, a viable function of the brain, is an adaptive mechanism to prevent overstimulation of nervous system. The aim of this study was to examine the effect of homobaric pure (i.e. 100%) oxygen on the human brain at different periods of inhalation. EEG was recorded while an auditory paired-click sensory gating test was conducted during 4 study periods: before inhalation of pure oxygen (Before), inhalation of 100% oxygen (air in control group) for 20 min (Oxy20) and 50 min (Oxy50), 30 min after oxygen (air in control group) inhalation (After). Each of the auditory stimuli elicited 4 clear peaks at 20, 39, 55 and 100 ms in ERPs, demonstrating that sensory gating is a multi-stage process. Comparing the S1-S2 differences of field potentials between two groups, significant experimental effects (P < 0.05-0.01) were shown at Oxy50 and After periods mainly at the 20 and 100 ms peak in ERPs. Pure oxygen was experimentally shown, for the first time, to affect the human brain activation, at the beginning of early P20 sensory cortical activation and late N100 auditory perception. The effect found in this study shall encourage further investigation on the oxygen treatment in human brain.

Both happy and sad melodies modulate tonic human heat pain.

UNLABELLED: The mechanism of music effects on pain perception remains to be elucidated. To determine which component (mood or valence) of music is more important in music-induced hypoalgesia, we compared the effects of 2 melodies with different moods (happy vs sad) but with the same degree of valence (pleasant vs unpleasant) to an affective neutral lecture and a control (baseline) on the objective and subjective responses to tonic heat pain. Our hypothesis was that if mood was the key component, the happy melody would reduce pain, whereas the sad one would exacerbate pain; and if valence is the key component, the 2 melodies would both alleviate pain. Twenty females participated in this study which consisted of 4 conditions (baseline, happy melody, sad melody, and lecture). Pain tolerance time (PTT), pain intensity, and distress dynamics and the characteristics of pain were measured. A newly devised multiple affective rating scale (MARS) was employed to assess the subjective experience of auditory perception. Both happy and sad melodies of equal valence resulted in significant lower pain ratings during the pain test and were in contrast to the mood prediction. These results indicate that the valence of music, rather than the mood it induced, appears to be the most likely mediator of the hypoalgesic effect of the different music. PERSPECTIVE: This article provides new evidence that the valence of music is more crucial than mood in affective pain modulation. This finding gives impetus for health professionals to manage pain more effectively in patients with proper music.

EEG default mode network in the human brain: spectral regional field powers.

Eyes-closed (EC) and eyes-open (EO) are essential behaviors in mammalians, including man. At resting EC-EO state, brain activity in the default mode devoid of task-demand has recently been established in fMRI. However, the corresponding comprehensive electrophysiological conditions are little known even though EEG has been recorded in humans for nearly 80 years. In this study, we examined the spatial characteristics of spectral distribution in EEG field powers, i.e., sitting quietly with an EC and EO resting state of 3 min each, measured with high-density 128-ch EEG recording and FFT signal analyses in 15 right-handed healthy college females. Region of interest was set at a threshold at 90% of the spectral effective value to delimit the dominant spatial field power of effective energy in brain activity. Low-frequency delta (0.5-3.5 Hz) EEG field power was distributed at the prefrontal area with great expansion of spatial field and enhancement of field power (t=-2.72, p<0.02) from the EC to the EO state. Theta (4-7 Hz) EEG field power was distributed over the fronto-central area and leaned forward from EC to the EO state but with drastic reduction in field power (t=4.04, p<0.01). The middle-frequency alpha-1 (7.5-9.5 Hz) and alpha-2 (10-12 Hz) EEG powers exhibited bilateral distribution over the posterior areas with an anterior field in lower alpha-1. Both showed significantly reduction of field powers (respectively, W=120, p<0.001 for alpha-1; t=4.12, p<0.001 for alpha-2) from EC to the EO state. Beta-1 (13-23 Hz) exhibited a similar spatial region over the posterior area as in alpha-2 and showed reduction of field power (t=4.42, p<0.001) from EC to the EO state. In contrast, high-frequency beta-2 and gamma band exhibited similar, mainly prefrontal distribution in field power, and exhibited no change from EC to the EO state. Corresponding correlation analyses indicated significant group association between EC and EO only in the field powers of delta (r=0.95, p<0.001) and theta (r=0.77, p<0.001) band. In addition, the great inter-individual variability (90 folds in alpha-1, 62 folds in alpha-2) in regional field power was largely observed in the EC state (10 folds) than the EO state in subjects. To summarize, our study depicts a network of spectral EEG activities simultaneously operative at well defined regional fields in the EC state, varying specifically between EC and EO states. In contrast to transient EEG spectral rhythmic dynamics, current study of long-lasting (e.g. 3 min) spectral field powers can characterize state features in EEG. The EEG default mode network (EEG-DMN) of spectral field powers at rest in the respective EC or EO state is valued to serve as the basal electrophysiological condition in human brain. In health, this EEG-DMN is deemed essential for evaluation of brain functions without task demands for gender difference, developmental change in age span, and brain response to task activation. It is expected to define brain dysfunction in disease at resting state and with consequences for sensory, affective and cognitive alteration in the human brain.

Somatosensory evoked potentials in the telencephalon of Atlantic salmon (Salmo salar) following galvanic stimulation of the tail.

Electric activity in the brain which is time-locked to a given stimulation of the somatosensory system can be recorded as a somatosensory evoked potential (SEP). We investigated whether a galvanic stimulation of the tail base in Atlantic salmon (Salmo salar) would elicit a SEP in the telencephalon. The telencephalon is central in learning and memory, and activity here may be a prerequisite for processing of external stimuli on a cognitive or emotional level. Anaesthetized salmon (n = 11) were subjected to craniotomy and a recording electrode was inserted into the telencephalon. The fish were given stimulations of four intensities, i.e., 2, 5, 10 and 20 mA. A SEP was elicited in the contralateral dorsal telencephalon for all intensities. This result agrees with findings in other fish species. Furthermore, there was a significant difference between the maximum peak amplitude and mean amplitude of the SEP elicited by putative non-noxious (2 mA) and putative noxious (20 mA) stimulation intensities (P < 0.01). The stronger stimulation intensities also tend to introduce longer-latencies components in the SEP. The results added to the body of literature indicates that the exteroceptive senses are represented by processing within the telencephalon of the fish.

The effect of reference choices on the spatio-temporal analysis of brain evoked potentials: the use of infinite reference.

Reference is a very virtual issue in EEG and ERP. Understanding the difference of various references will make the applications more confident. In this work, somatosensory evoked potential (SEP) with stimulation on the right hand was studied. The SEP spatio-temporal analysis was conducted comparatively on six references, left mastoid (contralateral mastoid reference, CM), right mastoid (ipsilateral mastoid reference, IM), linked mastoids (LM), average reference (AR), vertex reference (Cz) and the infinity reference (IR) newly proposed in 2001. Among the six, CM is the one used in actual recordings, and the other five are obtained by off-line re-referencing. The comparison is conducted on four selected components (P30 ms, P40 ms, N90 ms and P230 ms) in both temporal and spatial aspects. The results show that references may have a distinct influence on the amplitudes of the scalp potentials, with relative error at some electrodes larger than 500%, and for some electrodes it may even change the polarity. Pair-wise multiple comparison (Tukey test) shows that the differences of peak values among various references are very significant (P<0.001) between Cz and IR\CM\IM\LM, and significant (P<0.01) between Cz and AR for component N90 ms; very significant (P<0.001) between Cz and IR\CM\IM\LM\AR, significant between IMLM and AR (P<0.01), CM and AR (P<0.05) for component P230 ms. The amplitude value order is CM/IM> or =LM>IR>AR>Cz. The two-ways (the six references vs. the four Peaks) repeated measures ANOVA test shows the effect of different references depends on various components; there is a statistically significant interaction between reference and the peak (P=<0.001). While for the spatial map of the potential amplitude, references will not affect the amplitude map shape if the color-bar is selected automatically, but if a fixed color-bar is chosen for data of various references, they may show some differences. These results mean a common reference is important for producing a comparable result between labs. As IR is theoretically a constant reference, we recommend it as the common choice in the future.

Anticipatory electroencephalography alpha rhythm predicts subjective perception of pain intensity.

UNLABELLED: This high-resolution electroencephalography (EEG) study tested the hypothesis that the suppression of rolandic alpha power before predictable painful stimulation affects the subject's subsequent evaluation of pain intensity, as a reflection of the influence of expectancy processes on painful stimulus processing. High-resolution EEG data were recorded (126 channels) from 10 healthy adult volunteers during the expectancy of a painful CO(2)-laser stimulation at the right wrist. Surface laplacian estimation enhanced the EEG spatial information content over 6 scalp regions of interest (left frontal, right frontal, left central, right central, left parietal, and right parietal areas). Spectral power was computed for 3 alpha sub-bands with reference to the individual alpha frequency peak (about 5-7 Hz for alpha 1, 7-9 Hz for alpha 2, and 9-11 Hz for alpha 3). The suppression of the alpha power before the painful stimulation [as reflected by the event-related desynchronization (ERD)] indexed the anticipatory cortical processes. Results showed maximum (negative) correlations between the alpha 2 and alpha 3 ERD amplitude at the left central area and the subjective evaluation of pain intensity (P < .001). The stronger the anticipatory alpha 2 and alpha 3 ERD, the higher the subjective evaluation of pain intensity. For alpha 3, that correlation was confirmed even when the effect of habituation across the recording session was taken into account. These results suggest that the anticipatory suppression of the alpha rhythms over the contralateral primary sensorimotor cortex predicts subsequent subjects' evaluation of pain intensity, in line with its crucial role for the discrimination of that intensity. PERSPECTIVE: This electroencephalographic study showed that anticipatory activation/deactivation of sensorimotor cortex roughly predicts subjective evaluation of pain. This motivates further investigation on possible implications for the understanding of central chronic pain. Chronic pain patients might exaggerate the anticipatory activation of sensorimotor cortex to negligible pain stimuli.

Cortical characterization and inter-dipole distance between unilateral median versus ulnar nerve stimulation of both hands in MEG.

Contralateral somatosensory evoked fields (SEF) by whole head MEG after unilateral median and ulnar nerve stimulation of both hands were studied in 10 healthy right-handed subjects. Major parameters describing cortical activity were examined to discriminate median and ulnar nerve evoked responses. Somatic sensitivity showed high similarity in the 4 study conditions for both hand and nerve. The brain SEFs consisted of 7-8 major peak stages with consistent responses in all subjects at M20, M30, M70 and M90. Comparable inter-hemispheric waveform profile but high inter-subject variability was found. Median nerve induced significantly shorter latencies in the early activities than those of the ulnar nerve. The 3D cortical maps in the post stimulus 450 ms timeframe showed for both nerves two polarity reversals, an early and a late one which is a new finding. Dipole characteristics showed differential sites for the M20 and M30 in the respective nerve. Higher dipole moments evoked by the median nerve were noticed when compared to the ulnar. Furthermore, the results of the dipole distances between both nerves for M20 were calculated to be at 11.17 mm +/- 4.93 (LH) and 16.73 mm +/- 5.66 (RH), respectively after right hand versus left hand stimulation. This study showed substantial differences in the cortical responses between median and ulnar nerve. Especially the dipole distance between median and ulnar nerve on the cortex was computed accurately for the first time in MEG. Little is known however of the cortical responses in chronic pain patients and the parameter(s) that may change in an individual patient or a group. These results provide precise basis for further evaluating cortical changes in functional disorders and disease sequelae related to median and ulnar nerves.

Anticipation of somatosensory and motor events increases centro-parietal functional coupling: an EEG coherence study.

OBJECTIVE: Does functional coupling of centro-parietal EEG rhythms selectively increase during the anticipation of sensorimotor events composed by somatosensory stimulation and visuomotor task? METHODS: EEG data were recorded in (1) 'simultaneous' condition in which the subjects waited for somatosensory stimulation at left hand concomitant with a Go (or NoGo) visual stimulus triggering (50%) right hand movements and in (2) 'sequential' condition where the somatosensory stimulation was followed (+1.5 s) by a visuomotor Go/NoGo task. Centro-parietal functional coupling was modeled by spectral coherence. Spectral coherence was computed from Laplacian-transformed EEG data at delta-theta (2-7 Hz), alpha (8-14 Hz), beta 1 (15-21 Hz), beta 2 (22-33 Hz), and gamma (34-45 Hz) rhythms. RESULTS: Before 'simultaneous' sensorimotor events, centro-parietal coherence regions increased in both hemispheres and at all rhythms. In the 'sequential' condition, right centro-parietal coherence increased before somatosensory event (left hand), whereas left centro-parietal coherence increased before subsequent Go/NoGo event (right hand). CONCLUSIONS: Anticipation of somatosensory and visuomotor events enhances contralateral centro-parietal coupling of slow and fast EEG rhythms. SIGNIFICANCE: Predictable somatosensory and visuomotor events are anticipated not only by synchronization of cortical pyramidal neurons generating EEG power in parietal and primary sensorimotor cortical areas (Babiloni C, Brancucci A, Capotosto P, Arendt-Nielsen L, Chen ACN, Rossini PM. Expectancy of pain is influenced by motor preparation: a high-resolution EEG study of cortical alpha rhythms. Behav. Neurosci. 2005a;119(2):503-511; Babiloni C, Brancucci A, Pizzella V, Romani G.L, Tecchio F, Torquati K, Zappasodi F, Arendt-Nielsen L, Chen ACN, Rossini PM. Contingent negative variation in the parasylvian cortex increases during expectancy of painful sensorimotor events: a magnetoencephalographic study. Behav. Neurosci. 2005b;119(2):491-502) but also by functional coordination of these areas.