Integration and evaluation of magnetic stimulation in physiology setups.

A large number of behavioral experiments have demonstrated the existence of a magnetic sense in many animal species. Further, studies with immediate gene expression markers have identified putative brain regions involved in magnetic information processing. In contrast, very little is known about the physiology of the magnetic sense and how the magnetic field is neuronally encoded.

Electrical Coupling of Heterotypic Ganglion Cells in the Mammalian Retina.

Electrical coupling has been reported to occur only between homotypic retinal ganglion cells, in line with the concept of parallel processing in the early visual system. Here, however, we show reciprocal correlated firing between heterotypic ganglion cells in multielectrode array recordings during light stimulation in retinas of adult guinea pigs of either sex. Heterotypic coupling was further confirmed via tracer spread after intracellular injections of single cells with neurobiotin.

No influence of acute RF exposure (GSM-900, GSM-1800, and UMTS) on mouse retinal ganglion cell responses under constant temperature conditions.

Possible non-thermal effects of radio frequency electromagnetic fields (RF-EMF) on retinal ganglion cells were studied in vitro under conditions of constant temperature. Isolated mouse retinae were exposed to GSM-900, GSM-1800, and universal mobile telecommunication system (UMTS) RF-EMF applying specific absorption rates (SAR) of 0 (sham), 0.02, 0.

A system for precise temperature control of isolated nervous tissue under optical access: application to multi-electrode recordings.

Background: Since temperature severely affects all physiological processes, exact temperature control during electrophysiological measurements is indispensable. However, none of the tempering system approaches previously described is fully satisfactory for extracellular recordings with sharp multi-electrode arrays (MEAs).

New Method: We developed a set-up offering a homogeneously tempered and at the same time light-transparent stage for an ex vivo preparation.

High speed coding for velocity by archerfish retinal ganglion cells.

Background: Archerfish show very short behavioural latencies in response to falling prey. This raises the question, which response parameters of retinal ganglion cells to moving stimuli are best suited for fast coding of stimulus speed and direction.

Results: We compared stimulus reconstruction quality based on the ganglion cell response parameters latency, first interspike interval, and rate.

Temperature-controlled exposure systems for investigating possible changes of retinal ganglion cell activity in response to high-frequency electromagnetic fields.

Two exposure systems were developed for the measurement of retinal ganglion cell responses to light under the influence of pulsed high-frequency electromagnetic fields. Exposure characteristics were determined numerically for the GSM standards (900/1,800 MHz) and the UMTS standard (1,966 MHz) with specific absorption rates, averaged over the region of interest, of 0.02, 0.