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The following transcript is from a video recorded in 1998 in which Prof. Gary Lynch from the University of California at Irvine expressed his views on the future of the MED system.
"Well in the first place it's important, when considering the MED systemT, to understand that we're dealing with a very conventional methodology, that doesn't require you to change anything to what you already do with standard brain slice preparations. Anybody that is doing hippocampal slices, or cortical slices, can transfer immediately over to the MED device. It is important because it leads you to questions you already had without any further complexity; you just gain 64 stimulating and recording electrodes."
"With regards to the kinds of questions that we are using it for now, these are almost standard issue questions in neurophysiology. We look at current source density analysis; the MED system makes it possible for you to do at last, stimulation from different places within the brain tissue, in a much more naturalistic pattern. In other words, rather than a point source stimulation which is very un-physiological, you can do different electrodes, and switch between electrodes. So those kinds of experiments that have always been in the books, but we haven't been able to do in the past, we now can do. And again here, it's very important to realize, that you do not need to do anything different with this device. If you're doing cultured slices now, there's nothing further involved to start doing cultured slices with the MED system."
"The enormous advantage we get here, is that it makes it possible for us now to look at long-term effects, long-term meaning days or even weeks. Long-term physiological effects of manipulations that we couldn't have looked at before. The one that jumps out at you here is, of course, the long-term effects of drugs; neuroleptic drugs, stimulants, things of this sort. Now we can look at the idea, to apply it to the tissue for hours or days, and see how changes develop gradually over days."
"One thing that we didn't realize when starting working with this, is that the MED system comes with two different electrode arrays, one of them called the broad array, and the other called the dense array [the intermediate-size 300 mm Probe was not available at the time. N.B.]. That is really referring to the spacing between the electrodes. With the broad array it's perfectly possible to include the total hippocampal tri-synaptic system. Or even more, study the interaction between the hippocampus and subiculum, or retro-hippocampal cortex. With the neo- cortex, it is very simple to study the interactions between layers and adjacent regions. Using this broad array opens up the ability to study in vitro the interactions between subdivisions. The dense array has electrodes much closer together. They are much denser. With this you can begin to pick up the interactions and patterns that emerge, from within individual cells as well as within individual field potential levels of physiology. We can actually now see how the network level phenomenology emerges in a very simple way."
"Drugs create behavior and function by acting at the level of networks. Drugs influence the brain, as everyone knows, through many synapses and many neurons. Up to now we really haven't been able to look at that level of drug influence. We have been able to look at drug effects at an individual cell level, or in a whole animal. But we haven't been able to go in vitro and see what happens over dozens, even hundreds of neurons simultaneously. We can do that now. We have already seen some examples now, where the drugs are producing effects at the level of networks that are unexpected. And I have a feeling that these network level drug effects will be a new kind of pharmacology, and a pharmacology that may be much more predictive of what those drugs are going to do in an animal, that is in terms of behavior, than the more traditional single cell recording."
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"Anybody that is doing hippocampal slices, or cortical slices, can transfer
immediately over to the MED device."
"So those kinds of experiments that have always been in the books, but we haven't been able to do in the past, we now can do."
"We can actually now see how the network level phenomenology emerges in a very simple way."
"The one that jumps out at you here, is of course, the long-term effects of drugs; neuroleptics, stimulants [...]"
"And I have a feeling that these network level drug effects will be a new kind of pharmacology."
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