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Summary Background Although laparoscopic adhesiolysis for adhesive small bowel obstruction is being done more frequently, it is not widely accepted due to the lack of supporting evidence of its superiority over an open approach and concerns regarding its benefits. We aimed to investigate whether laparoscopic adhesiolysis was a superior treatment for adhesive small bowel obstruction compared with an open approach in terms of length of postoperative hospital stay and morbidity. Methods In this international, multicentre, parallel, open-label trial, we randomly assigned patients (1:1) aged 18–95 years who had adhesive small bowel obstruction that had not resolved with conservative management to have either open or laparoscopic adhesiolysis. The study was done in five academic university hospitals and three community (central) hospitals in two countries (Finland [n=3 academic university hospitals; n=3 community hospitals] and Italy [n=2 academic university hospitals]). We included only patients with high likelihood of a single adhesive band in the trial; additionally, patients who had an anaesthesiological contraindication, were pregnant, living in institutionalised care, or who had a hospital stay of more than 1 week before the surgical consultation were excluded from the trial. The randomisation sequence was generated using block randomisation, with randomly varied block sizes and stratified according to centre. The primary outcome was postoperative length of hospital stay assessed at time of discharge in the modified intention-to-treat population. Findings Between July 18, 2013, and April 9, 2018, 566 patients were assessed for eligibility, of whom 104 patients were randomly assigned to the open surgery group (n=51) or to the laparoscopy group (n=53). Of these patients, 100 were included in the modified intention-to-treat analyses (49 in the open surgery group; 51 in the laparoscopy group). The postoperative length of hospital stay for open surgery group was on average 1·3 days longer than that in the laparoscopy group (geometric mean 5·5 days [range 2–19] vs 4·2 days [range 1 −20]; ratio of geometric means 1·31 [95% CI 1·06–1·61]; p=0·013). 21 (43%) patients in the open surgery group and 16 (31%) patients in the laparoscopy group had postoperative complications (Clavien-Dindo any grade) within 30 days (odds ratio 0·61 [95% CI 0·27–1·38]; p=0·23). One patient died in each group within 30 days. Interpretation Laparoscopic adhesiolysis provides quicker recovery in selected patients with adhesive small bowel obstruction than open adhesiolysis. Funding Vatsatautien Tutkimussaatio Foundation, Mary and Georg Ehrnrooth's Foundation, Martti I Turunen Foundation, and governmental (Finland) competitive research funds (EVO/VTR/TYH).

We have previously shown age- and time-dependent effects on brain activity in the primary somatosensory cortex (SI), in a functional magnetic resonance imaging (fMRI) study of patients with median nerve injury. Whereas fMRI measures the hemodynamic changes in response to increased neural activity, magnetoencephalography (MEG) offers a more concise way of examining the evoked response, with superior temporal resolution. We therefore wanted to combine these imaging techniques to gain additional knowledge of the plasticity processes in response to median nerve injury. Nine patients with median nerve trauma at the wrist were examined with MEG. The N1 and P1 responses at stimulation of the injured median nerve at the wrist were lower in amplitude compared to the healthy side (p < .04). Ulnar nerve stimulation of the injured hand resulted in larger N1 amplitude (p < .04). The amplitude and latency of the response did not correlate with the sensory discrimination ability. There was no correlation between N1 amplitude and size of cortical activation in fMRI. There was no significant difference in N1 latency between the injured and healthy median nerve. N1 latency correlated positively with age in both the median and ulnar nerve, and in both the injured and the healthy hand (p < .02 or p < .001). It is concluded that conduction failure in the injured segment of the median nerve decreases the amplitude of the MEG response. Disinhibition of neighboring cortical areas may explain the increased MEG response amplitude to ulnar nerve stimulation. This can be interpreted as a sign of brain plasticity.

highlights In 46 healthy newborns, activity from both the primary (SI) and secondary somatosensory cortices (SII) was detectable with magnetoencephalography to tactile stimulation of the contralateral index finger dur- ing quiet sleep (QS). No significant interhemispheric differences in the responses from SI or SII existed. Within the neonatal period (postmenstrual age (PMA) between 37 and 44 weeks) PMA, height, or gen- der did not significantly affect the latency or strength of the somatosensory evoked magnetic fields (SEFs). abstract Objective: To determine interhemispheric differences and effect of postmenstrual age (PMA), height, and gender on somatosensory evoked magnetic fields (SEFs) from the primary (SI) and secondary (SII) somatosensory cortices in healthy newborns. Methods: We recorded SEFs to stimulation of the contralateral index finger (right in 46 and left in 12) healthy fullterm newborns and analyzed the magnetic responses with equivalent current dipoles. Results: Activity from both the SI and SII was consistently detectable in the contralateral hemisphere of the newborns during quiet sleep. No significant interhemispheric differences existed in SI or SII response peak latencies, source strengths, or location (n = 8, quiet sleep). SI or SII response peak latency or source strength were not significantly affected by PMA, height, or gender. Conclusions: During the neonatal period (PMA 37-44 weeks), activity from the contralateral SI and SII can be reliably evaluated with MEG. The somatosensory responses are similar in the left and right hemi- spheres and no corrections for exact PMA, height, or gender are necessary for interpreting the results. However, the evaluation should be conducted in quiet sleep. Significance: The reproducibility of the magnetic SI and SII responses suggests clinical applicability of the presented MEG method.

The primary hypothesis for this study was that epidural analgesia reduces the use of opioids and thus advances bowel function and oral intake and shortens hospital stay after laparoscopic sigmoidectomy performed according to principles of enhanced recovery after surgery. For this study, 60 patients with complicated diverticular disease were randomized to the epidural anesthesia group or the control group before surgery. Postoperative oxycodone consumption, pain, and recovery parameters were followed for 14 days. The epidural group needed less oxycodone than the control group until 12 h postoperatively. They experienced significantly less pain related to coughing and motion until postoperative day 2. In the epidural group, fewer patients experienced significant pain, and the duration of postoperative pain was shorter. Postoperative oral intake, bowel function, hospital stay, and overall complication rate were similar in the two groups. However, the control group had more postoperative hematomas. Epidural analgesia significantly alleviates pain, reducing the need for opioids during the first 48 h after laparoscopic sigmoidectomy. However, epidural analgesia does not alter postoperative oral intake, mobilization, or length of hospital stay.

We studied somatosensory evoked magnetic fields (SEFs) to electric and tactile stimulation in newborns. The electric stimulation was applied to the left median nerve at the wrist and the tactile stimulation to the tip of the left or right index finger. An interstimulus interval of 2 s was used. The evoked magnetic fields were measured over the right hemisphere with a 306-channel MEG-system (Elekta Neuromag Oy). The data were off-line analyzed for active and quiet sleep stages. The first deflection after the median nerve stimulation, M30, corresponding to the adult N20 m, peaked at about 30 ms. The field pattern of this early peak was dipolar, and the activity could be modeled using an equivalent current dipole (ECD). The coordinates of the ECD were in agreement with activity generated at the primary somatosensory cortex, the current dipole pointing anteriorly. The locations of the later deflections were compared with the origin of M30.

Objective : Our objective was to characterize the effects of sleep stages on tactile somatosensory evoked responses in full-term newborns. Methods : Somatosensory evoked potentials (SEPs) and magnetic fields (SEFs) to tactile stimulation of the tip of the index finger and/or thenar eminence were measured from 14 healthy newborns. The stimulus was a gentle tap produced by a moving membrane driven by an air-pressure pulse. Results : SEPs and SEFs to tactile stimulation of the skin were similar in waveform and latency to SEPs known to be produced by electrical stimulation of the fingertip of neonates. The two most distinguishable positive deflections of SEPs, P1 and P2, within 300 ms of the stimulation, and their magnetic counterparts were clearly smaller in active compared to quiet sleep. Conclusions : Our study demonstrates for the first time that it is possible to record SEFs in neonates, and that clear late cortical somatosensory responses are produced by tactile stimulation. In addition, the effect of sleep stage on these responses indicates differences in the processing of the incoming information, at least in the somatosensory modality, in active and quiet sleep. Significance : Tactile stimulation may be useful as a completely non-invasive technique for studying the physiology of the somatosensory system in neonates. Methodologically, since the effect of sleep stage is profound, one must carefully monitor the sleep stages in studies of event-related responses in newborns, or else this effect may confound the phenomena being studied.

Objectives : To examine in detail the activation of the primary (SI) and secondary (SII) somatosensory cortex in CLN5, the Finnish variant of late infantile neuronal ceroid lipofuscinoses (NCL). Methods : Somatory evoked magnetic fields were recorded with a 122-channel planar gradiometer in response to median nerve stimulation in 5 CLN5 patients (aged 8.8–16.7 years) and in 10 healthy age-matched controls. Results : The first two responses from contralateral SI, N20m and P35m, were 6–20 times stronger in the patients than in the controls. The morphology of the subsequent deflections from SI was abnormal in the patients: a prominent N45m was detected, while the normally present P60m deflection was missing. In 4 patients the contra- and in two patients the ipsilateral SII responses were also enlarged. Furthermore, the SII activation was detected at shorter latency in patients than in controls. Conclusions : At SI, CLN5 is associated with a selective enhancement of the early cortical responses. We propose that the enlargement of N20m most likely reflects increased synchronous input from thalamus, whereas the altered morphology of the following responses may reflect defective interneuronal inhibition at the cortex. The enlargement of SII responses shows that the imbalance between excitation and inhibition in CLN5 extends outside the primary somatosensory areas.

Background Laparoscopic adhesiolysis is emerging as an alternative for open surgery in adhesive small bowel obstruction. Retrospective studies suggest that laparoscopic approach shortens hospital stay and reduces complications in these patients. However, no prospective, randomized, controlled trials comparing laparoscopy to open surgery have been published. Methods/Design This is a multicenter, prospective, open label, randomized, controlled trial comparing laparoscopic adhesiolysis to open surgery in patients with computed-tomography diagnosed adhesive small bowel obstruction that is not resolving with conservative management. The primary study endpoint is the length of postoperative hospital stay in days. Sample size was estimated based on preliminary retrospective cohort, which suggested that 102 patients would provide 80% power to detect a difference of 2.5 days in the length of postoperative hospital stay with significance level of 0.05. Secondary endpoints include passage of stool, commencement of enteral nutrition, 30-day mortality, complications, postoperative pain, and the length of sick leave. Tertiary endpoints consist of the rate of ventral hernia and the recurrence of small bowel obstruction during long-term follow-up. Long-term follow-up by letter or telephone interview will take place at 1, 5, and 10 years. Discussion To the best of our knowledge, this trial is the first one aiming to provide level Ib evidence to assess the use of laparoscopy in the treatment of adhesive small bowel obstruction. Trial registration ClinicalTrials.gov identifier: NCT01867528. Date of registration May 26th 2013.

We studied event-related desynchronization (ERD) of the 8–13 Hz rhythm (mu rhythm) of the primary somatosensory cortex (SI) caused by contra- and ipsilateral median-nerve stimulation. We used whole-head magnetoencephalography (MEG) and wavelet analysis together with our newly developed color-coded single-trial ERD display. The somatosensory stimuli suppressed mu rhythm at both contra- and ipsilateral SI, but the attenuation was clearly lateralized, being at least 20% stronger contra- than ipsilaterally. Moreover, repeated stimulation significantly reduced mu-rhythm ERD in the ipsilateral but not in the contralateral hemisphere in the course of the experiment. The observed lateralization is in agreement with the classical concept of a dominant role of the contralateral hemisphere in the processing of somatosensory information. The strong ipsilateral ERD in the beginning of the experiment may reflect the presence of non-specific arousal-like activation, which attenuates toward the end of the experiment.

We studied recovery-induced changes in the responsiveness of the primary somatosensory cortex in stroke patients with sensory and/or motor symptoms. Somatosensory evoked magnetic fields, in response to median nerve stimulation, were recorded in 14 patients with their first symptomatic unilateral stroke 1 to 15 days from the first symptoms and again 2 to 3 months later. Neuronal activity at the contralateral primary somatosensory cortex was modeled with equivalent current dipoles at the peak latencies of the first two cortical deflections at about 20 msec (N1m) and at 28 to 91 msec (P1m). Twenty-three age-matched healthy volunteers, 9 of whom were tested also in serial recordings, served as control subjects. At follow-up, 6 patients showed a significant increase of P1m amplitude, whereas N1m increased only in 1. Clinical improvement of two-point discrimination ability, but not of other basic somatosensory skills, was significantly correlated with the increase of P1m. We conclude that the recovery of discriminative touch after stroke is paralleled by the growth of the P1m somatosensory evoked magnetic field deflection, and we propose that this may reflect re-establishment of lateral inhibitory functions at the primary somatosensory cortex. Ann Neurol 2000;47:353–360

We recorded somatosensory evoked magnetic fields (SEFs) to median nerve stimulation from 15 patients in the acute stage (1-15 days from the onset of the symptoms) of their first-ever unilateral stroke involving sensorimotor cortical and/or subcortical structures in the territory of the middle cerebral artery (MCA). Neuronal activity corresponding to the peaks of the N20m, P35m and P60m SEF deflections from the contralateral primary somatosensory cortex (SI) was modelled with equivalent current dipoles (ECDs), the locations and strengths of which were compared with those of an age-matched normal population. Four patients with pure motor stroke had symmetric SEFs. In one of the 4 patients with pure sensory stroke, and in 5 of the 7 patients with sensorimotor paresis, the SEFs were markedly attenuated or missing. All except one patient with abnormal SEFs had deficient two-point discrimination ability; especially the attenuation of N20m was more clearly correlated with two-point discrimination than with joint-position or vibration senses. Of the different SEF deflections, P35m and P60m were slightly more sensitive indicators of abnormality than N20m, the former being affected in two patients with symmetric N20m. Three patients with pure sensory stroke and lesions in the opercular cortex had normal SEFs from SI. We conclude that the SEF deflections N20m, P35m and P60m from SI are related to cutaneous sensation, in particular discriminative to touch. The results also demonstrate that basic somatosensory perception can be affected by lesions in the opercular cortex in patients with functionally intact SI.

It is well established that voluntary hyperventilation (HV) slows down electroencephalographic (EEG) rhythms. Little information is available, however, on the effects of HV on cortical responses elicited by sensory stimulation. In the present study, we recorded auditory evoked potentials (AEPs) and magnetic fields (AEFs), and somatosensory evoked magnetic fields (SEFs) from healthy subjects before, during, and after a 3- to 5-min period of voluntary HV. The effectiveness of HV was verified by measuring the end-tidal CO2 levels. Long-latency (100–200 ms) AEPs and long-latency AEFs originating at the supratemporal auditory cortex, as well as long-latency SEFs from the primary somatosensory cortex (SI) and from the opercular somatosensory cortex (OC), were all reduced during HV. The short-latency SEFs from SI were clearly less modified, there being, however, a slight reduction of the earliest cortical excitatory response, the N20m deflection. A middle-latency SEF deflection from SI at about 60 ms (P60 m) was slightly increased. For AEFs and SEFs, the center-of-gravity locations of the activated neuronal populations were not changed during HV. All amplitude changes returned to baseline levels within 10 min after the end of HV. The AEPs were not altered when the subjects breathed 5% CO2 in air in a hyperventilation-like manner, which prevented the development of hypocapnia. We conclude that moderate HV suppresses long-latency evoked responses from the primary projection cortices, while the early responses are less reduced. The reduction of long-latency responses is probably mediated by hypocapnia rather than by other nonspecific effects of HV. It is suggested that increased neuronal excitability caused by HV-induced hypocapnia leads to spontaneous and/or asynchronous firing of cortical neurones, which in turn reduces stimulus-locked synaptic events.

The objective of the present study was to evaluate the normal interhemispheric variability of the locations and activation strengths of the somatosensory cortices. Somatosensory evoked magnetic fields (SEFs) were recorded with a 122-channel magnetometer in 23 healthy subjects (mean age 57 years) to stimulation of left and right median nerves. Equivalent current dipole (ECD) strengths and locations were determined for the main SEF deflections at the contralateral primary sensorimotor (SMI) and secondary somatosensory (SIIc) cortices. In a Cartesian co-ordinate system, defined by the preauricular points and the nasion, the SMI sources were slightly but significantly more laterally and anteriorly located in the right than in the left hemisphere. No systematic co-ordinate asymmetries were found for the SIIc sources. In individual subjects, the interhemispheric differences in the ECD co-ordinates averaged less than 6 mm at both SMI and SIIc. The group means of the source strengths did not differ between the hemispheres, but individual differences were on average 20% for the SMI and 65% for the SIIc sources. We conclude that at the individual level, the median nerve SEFs from SMI can be used to detect abnormally large interhemispheric asymmetries of source locations in the centimetre scale.

Cerebral responses evoked by peripheral stimuli are known to depend critically on the interstimulus interval (ISI). Here we report on the effects of ISI on somatosensory evoked magnetic fields (SEFs) to right median nerve stimulation, obtained in 9 healthy adults with ISIs of 0.15, 0.3, 1, 3 and 5 s. At the contralateral (left) primary sensorimotor cortex (SMI), the first cortical response, N20m, was stable between the ISIs 0.3 and 5 s, but slightly attenuated at the shortest ISI of 0.15 s. In contrast, the P35m and P60m deflections were very sensitive to changes of the ISI, declining steadily with shortening of the ISI throughout the entire range. These deflections were frequently undetectable at the shortest ISI of 0.15 s. Concomitant with the reductions of P35m and P60m, an N45m deflection was enhanced toward the short ISIs. Responses from second somatosensory cortex (SII) and posterior parietal cortex (PPC) were seen only with ISIs of 1 s or greater, being strongest at the 5 s ISI. Based on known effects of the ISI on intracellular evoked potentials, we present the following tentative model for the generation mechanism of the SMI response: N20m represents early excitatory postsynaptic potentials (EPSPs), P35m early inhibitory postsynaptic potentials (IPSPs), N45m secondary EPSPs and P60m late IPSPs in pyramidal neurones of area 3b. For practical purposes, SEFs from SMI can be obtained with short ISIs, while responses from SII and PPC require an ISI of at least 1 s.

Backround and Aims: The aim of this study was to establish whether smoking is associated with complicated diverticular disease and adverse outcomes of operative treatment of diverticular disease. Smoking has been associated with increased rate of perforations in acute appendicitis as well as failure of colonic anastomosis in patients resected for colonic tumours. It has also been suggested that smoking is a risk factor for complicated diverticular disease of the colon. Material and Methods: Retrospective investigation of records of 261 patients electively operated for diverticular disease in Helsinki university Central Hospital during a period of five years. Results: The smokers underwent sigmoidectomy at a younger age than the non-smokers (p = 0.001) and they had an increased rate of perforations (p = 0.040) and postoperative recurrent diverticulitis episodes (p = 0.019). Conclusions: We conclude that smoking increases the likelihood of complications in diverticulosis coli. The development of complicated disease also seems to proceed more rapidly in smokers.

Auditory orienting and discrimination were studied with combined multi-channel EEG and MEG recordings in a patient with unilateral amygdala-hippocampus-partial temporal lobe resection of the right hemisphere. The results revealed abnormalities of habituation in alerting- and orienting-related responses, and discrimination-related responses, elicited by auditory stimulation contralateral to the resected cerebral hemisphere. These results give support to the notions about the role of the amygdala and hippocampus in alerting and orienting, respectively, and of the temporal cortex in auditory discrimination.

Objectives: Brain responses to auditory and visual stimuli have been previously shown to depend on the level of spontaneous brain activity in the 8‐13 Hz range. Our aim was to determine whether somatosensory evoked responses are influenced by ongoing rhythmic activity in the 8‐13 Hz frequency range originating in the sensorimotor cortex (mu rhythm). Methods: We used a whole-head 122 channel magnetoencephalography (MEG) system to record somatosensory evoked fields (SEFs) in response to median nerve stimulation in 11 subjects. Spontaneous oscillations in the 8‐13 Hz band over the contralateral sensorimotor cortex were evaluated in 3 different pre-stimulus time intervals using wavelet analysis. Results: The N20m SEF deflection did not depend on pre-stimulus activity, while the amplitude of the P35m deflection, and to a lesser extent that of the P60m deflection, showed a small positive correlation with the amplitude of the pre-stimulus mu rhythm. Although the amplitude of the mu rhythm varied by a factor of 2.3‐5, the maximum variations in P35m and P60m amplitude were only 21 and 12%, respectively. The latencies of the peaks were not affected by the strength of the pre-stimulus mu rhythm. Conclusions: It appears that the first excitatory cortical response (N20m) is independent of the oscillatory state (8‐13 Hz frequency range) of the sensorimotor cortex. Later parts of the response (P35m and P60m) are also relatively stable compared with the large variations in mu rhythm. q 2000 Elsevier Science Ireland Ltd. All rights reserved.

Somatosensory evoked fields (SEFs) following median nerve stimulation can be recorded from the contralateral primary sensorimotor cortex (SMI), from the second somatosensory cortex (SII) bilaterally and from contralateral posterior parietal cortex (PPC) [1],[2]. At SMI, the response can be divided into distinct N20m, P35m and P60m deflections, while SII responses are biphasic with peaks at 80–100 ms and about 150 ms. The latency of the PPC response is usually 80–100 ms.

Ascending sensory impulses play an important role in providing feedback information necessary for the programming of movements. Therefore, it could be expected that sensory input to the cortex is facilitated from a moving limb, as demonstrated in monkeys [1].

The amplitudes of many scalp-recorded evoked potential (EP) deflections are higher in females than in males, and in elderly than in young subjects. Since EPs critically depend on the electric conductivity of the cranium, it is not known whether these differences reflect age- and gender-dependent changes in the intensity of neuronal activation, or changes in the volume conductor. Evoked magnetic fields are not significantly affected by the conductivities of the cranial tissues and therefore reflect more directly the neuronal activation than EPs. We report here on the effects of age and gender on somatosensory evoked fields (SEFs) from the primary somatosensory cortex (SI) in 43 healthy subjects (21 males) aged from 20 to 73 years (males 51+/-18 years, females 51+/-14 years). The intensity of neuronal activation was estimated with equivalent current dipoles (ECDs) found at the peaks of the N20m, P35m and P60m deflections from the left SI after right median nerve stimulation. The peak latencies of N20m and P35m (but not of P60m) were shorter in females than in males. The N20m latency was positively correlated with age in males, but otherwise the latencies did not correlate with age. The ECD amplitudes did not differ between males and females for any of the deflections. The N20m ECD strength showed a significant positive correlation (r=0.39, p0.01) with age while P35m and P60m ECD strengths did not. The results thus did not disclose gender differences in the activation strengths of the somatosensory cortex, implying that such differences in evoked potentials may possibly be due to gender differences in the volume conductor. On the other hand, the results suggest a slight age-related increase in cortical excitability.

THE functional significance of the second somatosensory cortex (SII) is poorly understood. However, lesion and cortical stimulation studies indicate that SII may be involved in sensory aspects of tactile learning and in movement control. In the present study, we explored a possible role of SII in sensorimotor integration in humans using a multichannel magnetometer. Somatosensory evoked fields (SEFs) from SII to electrical stimulation of left and right median nerves were recorded in six healthy volunteers during rest and in different test conditions. Continuous cutaneous stimulation of the right hand or face reduced the SEFs to both left and right median nerve stimulation. Right-sided finger movements increased the SEFs to right, but not left, median nerve stimulation. The responses were equally enhanced by simple finger flexion movement and by a complex finger sequence. The suppression of SEFs by competing cutaneous inputs from different areas of the body indicates that the neurones underlying the responses receive inputs from large, bilateral receptive fields. The enhancement of sensory reactions to signals from the actively moving limb but not to those from the opposite limb indicates a spatial tuning of the SII neurones to behaviourally relevant input channels, also suggesting that SII is important for the integration of sensory information to motor programmes.

We report evidence for activation of ipsilateral primary sensorimotor cortex (SMI) after median nerve stimulation recorded with magnetoencephalography (MEG). We measured somatosensory evoked magnetic fields (SEFs) to median nerve stimulation with a 122-channel helmet-shaped magnetometer in 10 healthy subjects. In five, the magnetic field patterns suggested long-latency activation of the ipsilateral SMI. Source locations found by current dipole fitting corresponded to the SMI hand area, as determined by contralateral stimulation. Further evidence for the origin of the ipsilateral responses in SMI was provided by the suppression of these responses during movement of the contralateral fingers. Sensory input to ipsilateral SMI could play a role in sensorimotor integration of bilateral movements.

Although brain development has been actively investigated in animals, maturation of the cerebral cortex in human newborns is still poorly understood. This study aimed at characterizing the cortical areas participating in tactile processing in human neonates. Somatosensory-evoked magnetic fields were recorded from 21 healthy full-term newborns during natural sleep. Altogether, four cortical areas were activated by tactile stimulation: the contra- and ipsilateral primary (SI) and secondary (SII) somatosensory cortices. The contralateral SI was activated first in all the newborns. This early activity was not affected by the interstimulus interval or the sleep stage. The contralateral SII activation at around 200 ms was prominent in quiet sleep (QS) but attenuated in active sleep (AS). Activity in this area was strongly depressed by a faster rate of stimulation. Ipsilateral activity was seen in most subjects: more often in QS than AS. The ipsilateral activity originated from SII in most babies, but in some the ipsilateral SI was also activated. We conclude that both the contra- and ipsilateral SI and SII can participate in the processing of somatosensory information in human neonates.