In Focus: The Horga Lab

The Horga Lab is a psychiatry research lab that uses neuroimaging and cognitive methods to study the origins of the psychotic symptoms of schizophrenia, including hallucinations and delusions. Psychotic symptoms are some of the most debilitating symptoms experienced by people with schizophrenia, particularly when considering that roughly a third of patients do not respond adequately to current treatment methods. Led by Dr. Guillermo Horga, the lab works with patients with schizophrenia as well as those at clinical high risk for psychosis to further understand the neurobiological underpinnings of psychosis.

The lab is currently conducting a study that is examining the formation and maintenance of beliefs in unmedicated patients with schizophrenia. This study utilizes clinical assessments, behavioral paradigms, and MRI/fMRI scans to explore reasoning patterns in patients with schizophrenia, with the aim of developing a computational model that provides a unifying explanation of both hallucinations and delusions. 

These procedures involve only minimal risks and solely use non-invasive methods for investigating neurobiological and cognitive processes, like functional MRI and behavioral paradigms. Unlike clinical trials, this type of research does not provide any direct benefit to patients in terms of treatment; however, these “mechanistic” studies provide greater understanding of the mechanisms underlying an illness such as schizophrenia. These tools allow researchers to understand what changes in brain systems or cognitive processes may lead to the expression of an illness, which lay the foundation for developing effective treatments and can provide important information for patients to understand their own experiences. 

For instance, in previous work the lab discovered how changes in response to expectations of sounds can help explain why people who hear (hallucinated) voices through increase activity in the regions of the brain that respond when we listen to actual voices. They have also linked this type of changes in expectations to increases in the neurotransmitter dopamine, helping us propose a model connecting changes in this neurotransmitter and the common experience of hearing (hallucinated) voices that many of our patients report.

One ongoing study works with patients diagnosed with schizophrenia, schizoaffective disorder, or schizophreniform disorder, ages 18-55, who are not currently taking any medications. Participants in the study typically spend 3-4 in-person days completing behavioral and MRI procedures, in addition to a couple remote appointments with a psychologist. While this research study is not designed to directly benefit patients, the lab's experience is that many of their patients find their participation in the study to be highly rewarding. For some, it is just the benefit of having a regular schedule or the increased social interactions that occur while completing the study. Many participants enjoy participating in the behavioral tasks and getting the opportunity to have an MRI scan and work with the lab's team, while others find that the compensation for the study is helpful. Still others are intrigued to learn more about the underlying processes that might explain their symptoms, and often are more interested in this than in treatment with medication. The lab has had several participants go on to complete additional research studies at Columbia and other institutions after having a great experience. Many of them maintain a long-term relationship with the lab, checking in from time to time to see if they are running new studies. The researchers proudly take this to mean that they enjoy being part of their studies and that they feel stimulated and respected by the research team.