EEG Study Services
Charles River scientists typically use quantitative EEG and EMG in animal models together or independently based on the scientific study of interest. One common request for monitoring both brain and muscle activity is in the detection of sleep-wake states, seizure disorders, or neurological movement disorders like amyotrophic lateral sclerosis (ALS). Quantitative EEG assesses changes in sleep state and electrical activity associated with neurological disease models. Noninvasive EEG measurements are easily combined with other techniques like behavior testing, microdialysis, EMG, or other electrophysiological recordings.
Characterization of Alpha-Synuclein and Neurotransmitters During the Sleep-Wake Cycle of a Parkinson’s Disease Model Expressing Human Wild-Type Alpha-Synuclein
Quantitative EEG is used to determine the sleep-wake cycle of Parkinson’s disease animal models combined with microdialysis sampling of relevant neurotransmitters.
Understanding the effects of test compounds on the activity and function of the brain are essential in drug development, and Charles River can perform continuous EEG following acute or chronic compound treatment in combination with PK/PD studies and behavioral testing. Quantitative EEG is also frequently used to determine sleep-wake cycles for microdialysis sampling of neurotransmitters at the appropriate intervals for disease modeling.
Using Quantitative EEG in Your Studies
Understanding sleep patterns is essential in drug development. With our telemetry approaches, we can continuously monitor sleep activity and the effects of novel therapeutics on sleep patterns using the following assay readouts:
- Quantitative EEG with spectral analysis
- Slow wave sleep (SWS)/Non-rapid eye movement (NREM) sleep
- Paradoxical sleep (PS)/Rapid eye movement (REM) sleep
- Acute monitoring
- Chronic monitoring
- Seizure detection
Seizures are a hallmark of a dysfunctional brain. They can be caused by brain trauma, induction of noxious chemicals, in some cases therapeutic agents, and disorders such as epilepsy. This makes understanding seizure activity essential to understanding brain function and the function of novel therapeutics. We use telemetry, alone or in combination with other techniques, such as simultaneous video tracking, to monitor seizure activity. Our capabilities include:
- Acute seizure detection
- Chronic seizure monitoring
- Simultaneous video tracking
- Behavioral scoring
- Combination with microdialysis
Understanding the effects of test compounds on the activity and function of the brain are essential in drug development. We can perform continuous EEG following acute or chronic compound treatment. Capabilities include:
- Acute treatment
- Chronic treatment
- Combination with PK, PD, or behavior
- SLEEP-WAKE EEG | QUANTITATIVE EEG
Electromyography (EMG) measures muscle activation and is routinely used to detect neuromuscular abnormalities. EMG is performed in conjunction with a nerve conduction velocity (NCV) test to differentiate a muscle disorder from a neuromuscular disorder. Compound muscle action potential (CMAP) is another type of EMG readout that refers to a group of almost simultaneous action potentials from several muscle fibers in the same area evoked by stimulation of the supplying motor nerve. CMAP is recorded as a multi-peaked summated action potential. Both NCV and CMAP recordings provide useful information about neuromuscular activity, their junctions, and any defects.
Sleep-Wake Stage Analysis
Detection of sleep-wake states using quantitative EEG, EMG, and movement activity signals.
An example of EEG power spectrum over 24h recording:
An example of EMG activity over the same period:
Frequently Asked Questions (FAQs) for Quantitative EEG and EMG
How is quantitative EEG different than EMG?
Quantitative EEG monitors the activity of the whole brain. EMG monitors the activity of skeletal muscle fibers. They can be used independently or together to monitor brain activity and neuromuscular activity.
What does EMG record?
Electromyography (EMG) is an electrophysiology technique for evaluating and recording the electrical activity produced by skeletal muscles. EMG is performed using an instrument called an electromyograph to produce an electromyogram.
What is compound muscle action potential (CMAP)?
Compound muscle action potential (CMAP) consists of stimulating a nerve fiber and monitoring the response in the muscle. CMAP is the electrical readout from an EMG experiment.