Electrogastrography allows to determinate the dominant frequency of gastric E.C.A. (electrical control activity). The aim was to investigate the gastric E.C.A. in a population of patients suffering from non-organic dispepsia (N.O.D.). Eighteen controls (9 males, 9 females, mean age 46.4 years old, SEM 3.72, range 24-72) and 52 dyspeptic patients (18 males, 34 females, mean age 54.19 years old, SEM 2.38, range 17-86) were studied. Two skin surface electrodes Ag-2ClAg were placed on epigastric area following a probabilistic antral axe. Reference electrode was placed on the right quadrant skin. In 5 patients, recordings with needle and cutaneous electrode were compared. Analogic waves were filtered, digitalized and processed. Signals were analyzed using F.F.T. (Fast Fourier Transformated) Only the predominant frequency in each block was considered, and percentage of total abnormalities on total recording time lesser than 2 c.p.m. or more than 4 c.p.m. was accepted. Recording were taken in fast time during 30 minutes, and 30 minutes after a meal containing 230 Cal. Running spectral analysis with F.F.T. In 43 non-selected patients the gastric emptying time of a mixed meal marked with 99 Tc in the solid phase was studied.60.45% showed delayed gastric emptying. Mean of fast E.C.A. was 2.99 c.p.m. in controls, Vs 3.34 c.p.m. in dispeptic patients (p > 0.001). In the post-prandial period, mean of E.C.A. was 3.53 c.p.m. in N.O.D., and these differences were not significatives ("t", NS). 22% of controls showed isolated periods of tachygastria, but never more than 8% of the total recording time. It was seen seven six and forty five percent of arrhythmias were observed (71.15% tachygastria, 4.76% bradygastria, and 19.23% mixed) during post prandial recording in N.O.D. 48% of tachygastrias were between the range 30-60% of the time recording. Ninety six and one percent of patients with abnormal gastric emptying had gastric arrhythmias (0.05 > p > 0.02) Vs 50% in patients with normal gastric emptying. Needle recording increased about 200-300% the signal power. It would be the better choice in cases of hairy abdominal skin.a) More than 76% of patients with N.O.D. had abnormal recording of E.C.A. beyond these observed in controls; b) tachygastria was the more frequent abnormality observed; c) the more severe clinical cases were associated with bradygastria; d) No association between symptoms and abnormal gastric emptying was found; e) E.G.G. abnormalities were seen in 96% of patients with abnormal gastric emptying, Vs 50% in normal gastric emptying; f) Needle electrodes let a better recording of E.G.G. signal; g) No association was found between abnormalities in gastric emptying and/or E.G.G., and clinical subtypes of Dyspepsia.