The perirhinal cortex is known to play a role in recognition memory and visual perception of objects. A recent single-unit recording study adds to our understanding of perirhinal cortex function, suggesting that it may also play a role in evaluating the significance of objects in a context-dependent manner.

A multibarreled glass-coated tungsten microelectrode suitable for single-unit recording and iontophoresis in chronically behaving animals is described. The microelectrode was stiff enough to pass through the dura matter of behaving monkeys, and can be applied as a microiontophoretic electrode. The electrode is easy to build and usable in stabilized conditions after repeated penetrations.

Recent studies using modern functional imaging methods have provided insights into the brain areas involved in combining information across the senses, and the manner in which sensory signals are integrated within them. These findings are remarkably consistent with the results from single-unit recording in animals.

Extracellular, large scale in vivo recording of neural activity is mandatory for elucidating the interaction of neurons within large neural networks at the level of their single unit activity. Technological achievements in MEMS-based multichannel electrode arrays offer electrophysiological recording capabilities that go far beyond those of classical wire electrodes. Despite their impressive cha...

Recording simultaneous activity of a large number of neurons in distributed neuronal networks is crucial to understand higher order brain functions. We demonstrate the in vivo performance of a recently developed electrophysiological recording system comprising a two-dimensional, multi-shank, high-density silicon probe with integrated complementary metal-oxide semiconductor electronics. The syst...

Jackson A, Fetz EE. Compact movable microwire array for longterm chronic unit recording in cerebral cortex of primates. J Neurophysiol 98: 3109–3118, 2007. First published September 12, 2007; doi:10.1152/jn.00569.2007. We describe a small, chronically implantable microwire array for obtaining long-term unit recordings from the cortex of unrestrained nonhuman primates. After implantation, the de...

Multiple single-unit recording has become one of the most powerful in vivo electro-physiological techniques for studying neural circuits. The demand has been increasing for small and lightweight chronic recording devices that allow fine adjustments to be made over large numbers of electrodes across multiple brain regions. To achieve this, we developed precision motorized microdrive arrays that ...

Traditional multibarreled pipette electrodes are still widely used in microiontophoresis studies. Although better electrodes have been introduced, they are difficult and time-consuming to make. Construction of a carbon fiber recording and microiontophoresis assembly is described here. The construction of a carbon fiber electrode assembly is easy and carbon fibers have excellent characteristics ...

Previous single-unit recording studies have revealed that randomly selected pars reticulata neurons respond in a highly variable and complex fashion to intravenous administration of the dopamine agonist, apomorphine. The current studies were undertaken (1) to assess whether the variable pattern of responses of reticulata neurons to intravenous apomorphine correlates with their sites of projecti...

The tetrode, a bundle of four electrodes, has proven to be a valuable tool for the simultaneous recording of multiple neurons in-vivo. The differential amplitude of action potential signatures over the channels of a tetrode allows for the isolation of single-unit activity from multi-unit signals. The ability to precisely control the stereotaxic location and depth of the tetrode is critical for ...