Facilities, Technology, and Equipment

A wide variety of behavioral and physiological data can be gathered using the resources available at David King Hall and the Krasnow Institute. Listed here are some of the resources commonly used by students in their research.

 

 

Neurolucida

We have the latest version of Neurolucida. Neurolucida's capabilities allow for reconstruction of entire neurons in 3-D. Additionally, as the neuron is traced, a battery of measurements are made automatically, so that data on morphometric parameters such as neurite length, diameter, and spine density are immediately available. The system comprises the Neurolucida software, a BX51 Olympus microscope, an automated stage, and a 22 inch LCD monitor used to display strikingly clear digital pictures. These system capabilities allow for unparalleled precision in quantification of neuronal morphology.

 

Skinner Boxes

We have eight operant Skinner boxes used for self-administration experiments in rats. They are fully automated and can be used for cued and contextual conditioning with food or drug.

 

Fear Conditioning

We currently have two working fear conditioning systems. We have two chambers operating with the San Diego system and two chambers using the recently acquired CleverSys system. Both systems are fully automated for computerized measurement of freezing behavior and behavioral analysis of analgesics and anxiolytics, and are suitable for use with both rats and mice. Here, a Long-Evans rat is shown in one of the San Diego chambers.

  

Morris Water Maze

Our Morris water maze system works with the HVS 2020 system to collect behavioral data for both rats and mice. We have four pools measuring 6 ft., 5 ft., 4 ft., and 3 ft. in diameter, with a depth of 2 ft. The pools can be painted white or black to track dark or albino animals. We have platforms for Atlantis and moving platform paradigms. A camera is mounted above the maze and tracks movements through the HVS imaging system. The pool is surrounded by large black spatial cues mounted on a white background. The HVS 2020 system can also be used for other tracking tasks such as analysis of open field behavior.

 

Open Field and Place Preference

We have an open field system which may be used to study anxiety levels in rats and mice, especially in response to treatment with a drug. Smith lab is currently using a conditioned place preference (CPP) system to study Pavlovian conditioning cues in relation to drug-seeking behavior in rats. CPP is a potentially useful test for modeling human drug-seeking, craving, and relapse, as drug-associated cues can maintain drug-taking behavior long after the absence of a drug.

 

Novel Object

We have a novel object response system that has been used for rats and is undergoing pilot testing with mice. Animal behaivor is tracked by camera and analysed using the Clever Sys ObjectScan software.

 

Radial Arm Maze

We have radial arm mazes [both mouse- and rat-sized] manufactured by Lafayette Instrument.

 

Cryostats and Vibrotome

We have a two cryostats available for tissue sectioning. The newest model is a Tissue-Tek Cryo3 microtome/cryostat manufactured by Sakura, shown here. We also have a Vibrotome, which is ideal for sectioning fixed or perfused tissue such as Golgi-Cox stained brains

 

 

Rat Colonies

Our animal housing facilities provide living space for several inbred rat strains, primarily Sprague-Dawley and Long-Evans. Facilities exist in both David King Hall and the Krasnow Institute, so experiments may be conducted at both locations. We have capacity for both single and group housing, as well as enriched environment housing. Breeding and animal care is conducted in-house, allowing for careful control of breeding conditions and convenient access to all rodent models for experimentation. A separate breeding room within the colony is maintained to reduce stress on breeding mothers and unweaned pups.

 

Transgenic Mouse Colonies

The rat colony at David King Hall also provides space for transgenic mouse colonies, maintained by Drs. Flinn and Fryxell. Room 2037 houses the Flinn lab mouse colony, consisting of several cohorts of TgAPP2576 mice, which produce amyloid plaques mimicking those found in Alzheimer's disease. Animals may be single or group-housed, and have "enriched" environments with igloos, wheels, and rubber bones in their cages. Transgenic mice may be purchased or bred in-house.

 

Genotyping

Transgenic mice bred in-house can be genotyped in-house at the Fairfax or the Prince William campus. Tissue samples can be collected and DNA extracted very easily in Fairfax; in cooperation with the biology department on the third floor of David King Hall, DNA can be amplified using PCR and gels can be run in a few hours. Real-time PCR can be run at the Prince William campus.  Genotyping is also used in human studies, especially for study of working memory and aspects of attention.

 

Synchrotron Imaging

Dr. Flinn's trace metal analysis lab is devoted to the study of metals in learning and memory. To this end, students make frequent trips to the U.S. Department of Energy's Brookhaven National Laboratory in New York. There, they use both X-ray fluorescence and infrared spectroscopy to collect data on mouse, rat, and human tissue. Microprobe synchrotron X-ray fluorescence provides a way to quantitate levels of metals in tissue, while infrared spectroscopy allows us to measure levels of amyloid protein in different conformations.

 

 

Histochemistry

We have a chemistry lab in David King Hall, along with resources in Krasnow, to do many kinds of histochemical analysis. Rodent neural tissue can be perfused or fresh-frozen, sectioned with cryostat or vibrotome, and stained with a variety of stains. Prepared slides can be imaged with any of several microscopes, and we can do bright-field, dark-field, and fluorescent microscopy. We are also setting up a darkroom that will allow us to process films from autoradiography in situ hybridization in David King Hall.

On the left you see neurons stained with Golgi-Cox solution, which can be traced and reconstructed with the Neurolucida system. On the right is an amyloid plaque stained with Congo red solution, which produces apple-green birefringence when viewed under polarised light.

Driving Simulator

Our high fidelity open-cab driving simulator is equipped with a motion-base system capable of a single degree of pitch motion and a 90 +/- degree high-quality yaw motion, a 3-channel visual system covering 180-deg forward field-of-view, and a force-feedback steering wheel. It is equipped with a 7-inch touch-screen display with integrated prototyping software capable of simulating a wide range of in-vehicle interfaces that communicate with the simulator software in real-time.

Functional Magnetic Resonance Imaging

The George Mason MRI Center is housed in the Krasnow Institute, which occupies a large building with dedicated neuroscience laboratory space, including a vivarium. A 3 Tesla Siemens Allegra head MRI scanner (Siemens AG, Erlangen, Germany) optimized for best image quality and fast imaging of the brain is available for neuroimaging studies. This MRI scanner is equipped with a bird-cage coil to conduct neurocognitive functional MRI research including advanced neuroimaging applications such as T1-, T2- weighted, diffusion, multi-directional diffusion imaging, perfusion, and spectroscopy sequences. The fMRI stimulus delivery includes a FDA approved visual system.

Eye Trackers

The Arch Lab has more than 6 eye trackers including non-invasive desk-mounted systems, a high-speed 500 Hz head-mounted Eyelink 2 eye tracker, and Pupil Pro. The high-speed system allows for real-time gaze-contingent display changes, including the ability to make display changes during saccadic eye movements. Because visual processing is suppressed during saccades, this allows us to use saccadic suppression to mask environmental changes, allowing us to better assess situational awareness. In addition, the real-time nature of the high-speed system allows us to simulate augmented reality.

Oculus Rift

The Oculus Rift is a virtual reality head-mounted display that can turn almost any environment on a conventional monitor or television into a 3D virtual world. The field of view is more than 90 degrees horizontal (110 degrees diagonal), which is more than double the FOV of most competing devices, and is the primary strength of the device. It is intended to almost fill the wearer's entire field of view, and the real world is completely blocked out, to create a strong sense of immersion. It uses a combination of 3-axis gyros, accelerometers, and magnetometers, which make it capable of absolute (relative to earth) head orientation tracking without drift. 

Electroencephalography (EEG)

EEG is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain. Event-related potentials (ERPs) represent the brain's neural response to specific sensory, motor, and cognitive events. ERPs are computed by recording the EEG and by averaging EEG epochs time-locked to a particular stimulus or response event.

Transcranial Magnetic Stimulation (TMS)

TMS is a noninvasive method that causes depolarization or hyperpolarization in the neurons of the brain. TMS uses electromagnetic induction to induce weak electric currents using a rapidly changing magnetic field; this can cause activity in specific or general parts of the brain with minimal discomfort, allowing for study of the brain's functioning and interconnections.

Transcranial Direct Current Stimulation (tDCS)

tDCS is a form of neurostimulation which uses constant, low current delivered directly to the brain area of interest via small electrodes.  The stimulation changes the cortical excitability of the region being stimulated.

Functional Near-Infrared Spectroscopy (fNIRS)

fNIRS typically uses near-infrared light that is emitted by several sources embedded in a strap that is placed over the front of the head. The strap also contains several infrared detectors that detect light after it has passed through the skull and brain. Changes in light absorption, typically measured at two wavelengths, are used to calculate relative changes of oxygenated and deoxygenated blood in the frontal cortex.
 

BioHarness 3

The BioHarness is a wireless Electrocardiography (ECG) that is used to assess the electrical and muscular functions of the heart. In addition to heart rate and heart rate variability measures, the BioHarness can also measure EDR, respiration (breathing rate), temperature, acceleration, and changes in posture.

Electrodermal Response (EDR)

EDR is a method of measuring the electrical conductance of the skin, which varies with its moisture level. This is of interest because the sweat glands are controlled by the sympathetic nervous system, so skin conductance is used as an indication of psychological or physiological arousal.

Meka S2 Humanoid Head

The Meka S2 Humanoid Head is a seven degree-of-freedom robotic active vision head. The S2 system features high resolution FireWire cameras in each eye, integrated DSP controllers, zero-backlash Harmonic Drive gearheads in the neck, and Meka M3 and ROS software stacks.

Transcranial Doppler Sonography (TCD)

TCD measures blood flow velocity. Blood flow velocity is recorded by emitting a high-pitched sound wave from the ultrasound probe, which then bounces off of various materials to be measured by the same probe. A specific frequency is used (usually a multiple of 2 MHz), and the speed of the blood in relation to the probe causes a phase shift, wherein the frequency is increased or decreased. This frequency change directly correlates with the speed of the blood, which is then recorded electronically for later analysis.

Google Glass

Google Glass is a type of wearable technology with an optical head-mounted display (OHMD). Google Glass displays information in a smartphone-like hands-free format. Wearers communicate with the Internet via natural language voice commands.