The HD EEG and Psychophysiology Lab is located in room 256 of the Human Ecology Building.
The HEP Lab employs state-of-the-art equipment and powerful computational resources.
Electroencephalography (EEG) and Electromyography (EMG):
We collect data with a BioSemi ActiveTwo high-density EEG setup. We have caps to fit most heads, including children age 3 and older, and can record from up to 128 scalp electrodes. Additionally, the system has 8 extra electrodes that can be placed anywhere on the head or body; for EEG studies, they are generally placed near the eyes and used to account for the electrical activity caused by eye movements and blinks. These electrodes can also be used on their own to measure facial muscle activity, called facial electromyography (EMG), a potent assay of emotional reactions to stimuli. While recording from these electrodes, the system can also monitor galvanic skin response (GSR) through another two electrodes.
The HEP Lab uses several enhancements to optimize the quality of EEG data acquisition. Signa Gel® creates a conductive bridge to the scalp and along with the BioSemi "active" electrode system, this eliminates the need for traditional (painful and time-consuming) methods of electrode site preparation. Furthermore, participants are situated in an electromagnetically shielded booth during experiments. This setup shields participants from ambient electrical/magnetic fields created by standard electronic devices, greatly increasing the signal-to-noise ratio. It also imparts a strong sense of privacy. More information on our EEG equipment can be found at the BioSemi website.
We also offer wireless "sparse array" EEG headsets from Emotiv, featuring 14 active electrodes, quick set-up, and which enable researchers to use non-traditional (i.e. mobile) experiment designs.
Inside the experimental booth is an SR Research EyeLink CL eye-tracking system. This enables simultaneous recording of eye-tracking data with other measurement modalities, such as EEG, skin conductance, etc. For experiments that are concerned solely with eye movements, a head mount can be used that allows for eye position to be recorded at a sampling of up to 1 KHz for monocular tracking, or 500 Hz for binocular tracking. More information can be found at the SR Research website.
Other Psychophysiology modalities:
The HEP Lab can also collect other psychophysiology modalities, including skin conductance, facial EMG (facial muscle activity), and ECG (heart activity), using our BioSemi system. We also have a Biopac MP100 system, which interested users can inquire more about with the HEP Lab management. More information on the BioSemi equipment can be found on their website, and more information about the BIOPAC acquisition and analysis software, Acqknowledge, can be found here: http://www.biopac.com. We also have a different brand of wireless skin conductance sensor, from the Affectiva company, called Q Sensors.
We can also perform event-related analyses of psychophysiology data, such as the decomposition of skin conductance data into tonic (i.e., "baseline") and phasic (i.e., "response") components.
Stimuli Presentation Software:
Stimulus presentation occurs via a Silicon Graphics GDM and a 17E21 monitor with a 17" screen and a 75Hz refresh rate. This monitor's refresh cycle can be locked onto by stimuli-presentation software, allowing for precision timing in experiments.
All the stimulus-presentation software are capable of sending stimulus information to the psychophysiology data acquisition softwares, so that psychophysiology data can later be matched in a temporally precise fashion with the corresponding stimuli.
Data Analysis Software:
Several versions of MATLAB are installed on powerful Windows and Macintosh computers for data analysis of most of our data analysis software. EEG and EMG data are analyzed with the help of the EEGLAB toolbox, available for free download from: http://sccn.ucsd.edu/eeglab/
Additionally, we run several additional open-source MATLAB toolboxes, such as SPM (fMRI and EEG data analysis), LedaLab (skin conductance). The SPM8 software is available for free by clicking here: http://www.fil.ion.ucl.ac.uk/spm/software/spm8/