The electroencephalogram (EEG) is a mainstay of clinical neurology and is tightly correlated with brain function, but the specific currents generating human EEG elements remain poorly specified because of a lack of microphysiological recordings. The largest event in healthy human EEGs is the K-complex (KC), which occurs in slow-wave sleep. Here, we show that KCs are generated in widespread cortical areas by outward dendritic currents in the middle and upper cortical layers, accompanied by decreased broadband EEG power and decreased neuronal firing, which demonstrate a steep decline in network activity. Thus, KCs are isolated “down-states,” a fundamental cortico-thalamic processing mode already characterized in animals. This correspondence is compatible with proposed contributions of the KC to sleep preservation and memory consolidation.

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Current source densities in different layers of the human entorhinal cortex (ER) were recorded using a linear array of 24 microelectrodes during three memory conditions: a remote autobiographical condition eliciting recollections of events that occurred 10 or more years ago in the participant's past, a semantic icon condition invoking the mental image of a well-known object, and a semantic knowledge condition asking about general information. Our data demonstrate theta, gamma, and delta oscillations in left ER particularly for remote autobiographical memory. Gamma is predominant in hippocampally projecting layers during presentation of the memory cue, whereas theta is prolonged and dominant in cortically projecting layers during memory retrieval. Gamma interactions between ER and hippocampal formation (HF) may elicit an HF contribution to recall under influences relayed from the association cortex (AC). This contribution may then be relayed back to AC during retrieval of the memory orchestrated by theta interactions with ER. Accordingly, theta oscillations were recorded simultaneously in frontal and temporal cortices.

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BackgroundAnterolateral Minithoracotomy (ALMT) for the radical correction of Congenital Heart Defects is an alternative to Median Sternotomy (MS) due to reduce operative trauma accelerating recovery and yield a better cosmetic outcome after surgery. Our purpose is to conduct whether ALMT would bring more short-term benefits to patients than conventional Median Sternotomy by using a meta-analysis of case–control study in the published English Journal.Methods6 case control studies published in English from 1997 to 2011 were identified and synthesized to compare the short-term postoperative outcomes between ALMT and MS. These outcomes were cardiopulmonary bypass time, aortic cross-clamp time, intubation time, intensive care unit stay time, and postoperative hospital stay time.ResultsALMT had significantly longer cardiopulmonary bypass times (8.00 min more, 95% CI 0.36 to 15.64 min, p = 0.04). Some evidence proved that aortic cross-clamp time of ALMT was longer, yet not significantly (2.38 min more, 95% CI −0.15 to 4.91 min, p = 0.06). In addition, ALMT had significantly shorter intubation time (1.66 hrs less, 95% CI −3.05 to −0.27 hrs, p = 0.02). Postoperative hospital stay time was significantly shorter with ALMT (1.52 days less, 95% CI −2.71 to −0.33 days, p = 0.01). Some evidence suggested a reduction in ICU stay time in the ALMT group. However, this did not prove to be statistically significant (0.88 days less, 95% CI −0.81 to 0.04 days, p = 0.08).ConclusionALMT can bring more benefits to patients with Congenital Heart Defects by reducing intubation time and postoperative hospital stay time, though ALMT has longer CPB time and aortic cross-clamp time.