High-density event-related potentials: Current theories and practice

Event-Related Potentials (ERPs) are changes in the ongoing electrical activity of the brain (Electroencephalograms, or EEGs) which are caused by the specific occurrence of a cognitive, motor or perceptual event. Any changes in EEG due to the demands of the task are amplified, averaged and extracted as ERP waveforms (see Figure 1). These wave-forms are measured as the difference between the electrical activity of a baseline reference electrode attached to an electrically inactive site, such as the mastoid bone below the ear or the naison on the nose, and the electrical activity of the areas of the brain covered by the electrodes. These changes allow neuroscientists to determine what areas of brain are being stimulated at a given time (and therefore which brain areas are involved in a given process), precisely when these areas become activated and what happens in these areas when people make an error

Mechanisms of Oral Tolerance

Oral tolerance is an active process of local and systemic immune unresponsiveness to orally ingested antigens such as food. The gut immune system must balance responses to commensal bacteria (microbiome), innocuous antigens and pathogens. While it is clear that specialized populations immune cells and lymph nodes create a unique environment in the gut, there remains evidence to suggest that systemic effector sites are also critical to establishing and maintaining oral tolerance

Electric dipole moment enhancement factor of thallium

The goal of this work is to resolve the present controversy in the value of the EDM enhancement factor of Tl. We have carried out several calculations by different high-precision methods, studied previously omitted corrections, as well as tested our methodology on other parity conserving quantities. We find the EDM enhancement factor of Tl to be equal to -573(20). This value is 20% larger than the recently published result of Nataraj et al. [Phys. Rev. Lett. 106, 200403 (2011)], but agrees very well with several earlier results.Comment: 5 pages; v2: link to supplemental material adde

Interleukin-10 (IL-10) but not Lipopolysaccharide (LPS) produces increased motor activity and abnormal exploratory patterns while impairing spatial learning in Balb/c mice

Lipopolysaccharide (LPS) is a potent endotoxin, which produces âsickness behavioursâ including loss of weight, loss of interest in food and decreased exploration. LPS has also been shown in some studies to cause deficits in various learning and memory abilities, while in others these LPS-induced learning impairments have been attributed to performance-related deficits rather than learning deficits per se. Here, we use the novelty-preference paradigm, a task that minimises performance-related factors such as motivation, in an attempt to extract and examine the effects of LPS on spatial learning. In addition, some studies have indicated that the anti-inflammatory cytokine Interleukin-10 (IL-10) can alleviate some of the symptoms induced by LPS. Here, we also examine the effect of IL-10 on feeding, motor and learning behaviours. We demonstrate that a single injection of LPS does produce a lack of interest in food and weight loss; LPS, however, does not impair habituation in the noveltypreference paradigm. Furthermore, co-injection of IL-10 with LPS does not attenuate the LPS-induced effects of weight loss and lack of food intake. Interestingly, a single injection of IL-10 produces abnormal patterns of exploration, a general increase in activity and abnormal patterns of habituation

Hyperfine and Zeeman interactions of the a(1)[3Σ1+]a(1)[^3\Sigma^+_1] state of PbO

The role of the interaction with the nearest electronic state $^3\Sigma^+_{0^-}$ on the hyperfine structure and magnetic properties of the $a(1)[^3\Sigma^+_1]$ state of PbO is assessed. The accounting for this contribution leads to difference between $g$-factors of the $J=1$ $\Omega$-doublet levels, $\Delta g = 37\times10^{-4}$, that is in a good agreement with the experimental datum $\Delta g = 30(8)\times10^{-4}$. The contribution of this interaction rapidly grows with $J$. For $J=30$ the difference of $g$-factors of $\Omega$-doublet states reaches 100%; for hyperfine constants it is 18%. These differences also depend on the electric field and for $E=11$ V/cm for $^{207}$PbO the difference in $g$-factors turn to zero. The latter is important for suppressing systematic effects in the electron electric dipole moment search experiment

`St\"uckelberg interferometry' with ultracold molecules

We report on the realization of a time-domain `St\"uckelberg interferometer', which is based on the internal state structure of ultracold Feshbach molecules. Two subsequent passages through a weak avoided crossing between two different orbital angular momentum states in combination with a variable hold time lead to high-contrast population oscillations. This allows for a precise determination of the energy difference between the two molecular states. We demonstrate a high degree of control over the interferometer dynamics. The interferometric scheme provides new possibilities for precision measurements with ultracold molecules.Comment: 4 pages, 5 figure