Magnetic resonance imaging (MRI)

MRI experiments in the Adolphs Lab are performed at the California Brain Imaging Center (CBIC).  The CBIC  a core facility operated by the Caltech Division of Humanities and Social Sciences in association with the Caltech Division of Biology and Biological Engineering.  Adolphs Lab studies are conducted using a Siemens TIM-Trio 3 Tesla MR scanner with  12 channel and 32 channel phased array-headcoils. The facility is equipped to collect behavioral and physiological measures during the MRI scans, including eye-movements, 3D motion, galvanic skin response, pulse oximetry, respirations and EEG. The CBIC also provides access to a 0-Tesla Pre-training room, EEG/TMS Lab, olfaction stimulus hardware, and on site coil-building / electronic lab. A staff physicist (J. Michael Tyszka) oversees all imaging research.

This picture at the left is of a study in an MRI machine.  The same machine is used to record both structural and functional information.

  • Structural MRI gives us structural information about brains — how large certain regions are, and what their overall shape is.  
  • Functional MRI allows us to see how active brain regions are during specific tasks and can help us understand cognition, emotion, and behavior.  
  • Neural connectivity modeling integrates functional magnetic resonance imaging and diffusion magnetic resonance imaging to examine long-range cortical and subcortical connections between functional brain regions.  

The images to the right show examples of how different parts of the brain, shown here in cross section, are connected. The blue fibers are connections.

By scanning the structure and function of the brain, we are able to obtain important information about social functioning.  A participant typically lies in the scanner for about one hour during the experiment.  There is no radiation or drugs involved.  However, you cannot participate if you have a pacemaker or metallic implants in your body.

Eye-Tracking & Physiology

For behavioral experiments conducted independent of MRI, the Adolphs Lab uses a Tobii Eye-tracking system.  Eye-tracking technology enables researchers to record exactly where people’s eyes are focused when looking at pictures on a computer. When interacting with another person, we can also measure fixations made on that person’s face.   

Psychophysiological measurements such as heart rate and respiration are recorded using a Biopac hardware.  

None of these measures are invasive– you don’t feel the eyetracking at all, and the psychophysiology feels like wearing a band-aid.