Small, achromatic circular sinusoids were presented in the central and peripheral visual fields to investigate dorsal visual stream activation. It was hypothesized that peripheral stimulation would lead to faster onset latencies, as well as preferentially activate dorsal stream visual areas relative to central field stimulation. Although both central and peripheral stimulation activated similar...

In magnetoencephalography (MEG) a primary current is activated within a bounded conductive medium, i.e., the head. The primary current excites an induction current and the total (primary plus induction) current generates a magnetic field which, outside the conductor, is irrotational and solenoidal. Consequently, the exterior magnetic field can be expressed as the gradient of a harmonic function...

There is currently a debate as to whether event-related potentials and fields measured by using electroencephalography or magnetoencephalography are generated by ongoing oscillatory activity becoming phase-reset in response to a given stimulus. We performed a magnetoencephalography study measuring brain activity in response to visual stimuli. Using a measure termed the phasepreservation index w...

This chapter concerns the processes through which auditory sensory information is converted into a perceptual representation relevant for behavior. We describe a series of experiments where subjects listened to faint tones appearing amidst background noise, and were instructed to respond as fast as possible when they detect the tonal objects. Simultaneous psychophysical and brain imaging (MEG) ...

Effects of long-period musical training from childhood on the brain have been studied psychologically [1], anatomically [2], and functionally [36]. Absolute pitch, which is the ability to identify the note of a tone without any reference, is one of the most outstanding results of musical training. It seems that possessors of the absolute pitch have a memory of musical pitch in their brain. A PE...

The problem of determining the neuronal current inside the brain from measurements of the induced magnetic field outside the head is discussed under the assumption that the space occupied by the brain is approximately spherical. By inverting the Geselowitz equation, the part of the current which can be reconstructed from the measurements is precisely determined. This actually consists of only c...

We investigated the process of amodal completion in a same-different experiment in which test pairs were preceded by sequences of two figures. The first of these could be congruent to a global or local completion of an occluded part in the second figure, or a mosaic interpretation of it. We recorded and analyzed the magnetoencephalogram for the second figures. Compared to control conditions, in...

With the rapid expansion of city scale and the excessive concentration of population, achieving relative equality of extracurricular education resources and improving spatial service performance of relevant facilities become necessary arduous tasks. In urban space, extracurricular education facilities should offer better service to its targeted area and promote the equality and efficiency of ed...

We propose an adaptive classification method for the Brain Computer Interfaces (BCI) which uses Interaction Error Potentials (IErrPs) as a reinforcement signal and adapts the classifier parameters when an error is detected. We analyze the quality of the proposed approach in relation to the misclassification of the IErrPs. In addition we compare static versus adaptive classification performance ...

In this paper we present a prewhitening strategy to decorrelate the noise in space and in time. We discuss in detail how the effects of the filtering can be seen in the singular value decomposition of the data and we demonstrate how the approach can be used with an objective, statistical signal subspace estimation algorithm.