Standardized automated training of rhesus monkeys for neuroscience research in their housing environment.

Teaching nonhuman primates the complex cognitive behavioral tasks that are central to cognitive neuroscience research is an essential and challenging endeavor. It is crucial for the scientific success that the animals learn to interpret the often complex task rules and reliably and enduringly act accordingly. To achieve consistent behavior and comparable learning histories across animals, it is desirable to standardize training protocols.

A cage-based training, cognitive testing and enrichment system optimized for rhesus macaques in neuroscience research.

In neurophysiological studies with awake non-human primates (NHP), it is typically necessary to train the animals over a prolonged period of time on a behavioral paradigm before the actual data collection takes place. Rhesus monkeys (Macaca mulatta) are the most widely used primate animal models in system neuroscience. Inspired by existing joystick- or touch-screen-based systems designed for a variety of monkey species, we built and successfully employed a stand-alone cage-based training and testing system for rhesus monkeys (eXperimental Behavioral Intrument, XBI).

The physiological origin of task-evoked systemic artefacts in functional near infrared spectroscopy.

A major methodological challenge of functional near-infrared spectroscopy (fNIRS) is its high sensitivity to haemodynamic fluctuations in the scalp. Superficial fluctuations contribute on the one hand to the physiological noise of fNIRS, impairing the signal-to-noise ratio, and may on the other hand be erroneously attributed to cerebral changes, leading to false positives in fNIRS experiments. Here we explore the localisation, time course and physiological origin of task-evoked superficial signals in fNIRS and present a method to separate them from cortical signals.

Hemodynamic signals correlate tightly with synchronized gamma oscillations.

Functional imaging methods monitor neural activity by measuring hemodynamic signals. These are more closely related to local field potentials (LFPs) than to action potentials. We simultaneously recorded electrical and hemodynamic responses in the cat visual cortex.

Precise placement of multiple electrodes into functionally predefined cortical locations.

Current research on topics such as effective connectivity, neuronal coding strategy or signal propagation in the central nervous system requires simultaneous recordings from multiple sites within functionally grouped but topologically distributed neuronal clusters. We have addressed this issue by characterization of the cortical functional architecture using optical imaging of intrinsic signals (OI) and subsequent placement of multiple, individually adjustable electrodes into pre-selected domains. In order to achieve maximum precision and flexibility for the positioning of electrodes, a plastic cylinder containing channels of an extremely high aspect ratio (density >20 channels/mm(2)) was fixed above the cortex and individual channel positions were superimposed onto the functional maps of orientation columns obtained previously with OI.