Figure 3: Complete 8-channel transmit array in acrylic former Figure 4: Gradient echo images (TR=250 ms) of the individual coil elements shown in successive order, starting with the bottom element and working counter clockwise. There is no evidence of coupling with the body coil. The images were acquired using commercial power amplifiers and the conversion modules. RF transparent array for test...

In 1914, Blondel [1] performed an experiment in which a solenoidal coil was coaxial with a region of static magnetic field, such that the magnetic field on the conductor of the coil was negligible. The conductor of the coil T (D in the right figure) could be wound onto an auxiliary drum T ′ (D1), such that the magnetic flux through the coil T (D) was time dependent. What was the reading of the ...

The first CIs in the 1960s were singlechannel electrodes; multiple electrodes were introduced in the 1980s in Australia (Figure 1). The basic components of the CI comprise are illustrated in Figure 2: externally worn speech processor (A); a transmitting coil and magnet (B); and surgically implantable receiver/stimulator and electrode (C). Sound is detected by the microphone; a signal is transmi...

Motor responses evoked by transcranial magnetic stimulation OMS) or transcranial electrical stimulation (TCS) can be facilitated by a prior conditioning stimulus to an afferent nerve. Two facilitation periods are described short (SI), when the nerve stimulus is given near 0 to 10 ms after cranial stimulation, and long (LI), when nerve stimulation is given 25-60 ms before the cranial stimula...

The efficacy of transcranial magnetic stimulation (TMS) is determined by the magnitude and direction of the induced electric field in the cortex. The electric field distribution is influenced by the conductivity structure, in particular, the size of the head and the shapes of conductivity boundaries. We show that neglecting the head size can result in overestimating the stimulus intensity by a ...