Cilia are tiny, hair-like structures that are found on the surface of cells in the body. They are known to play important roles in various bodily functions, including perception of the environment and moving fluids. In the brain, cilia have been found to play a crucial role in the striatum, a region that is involved in movement, motivation, and time perception.
Researchers at the University of California, Irvine performed a recent study that found that the removal of cilia from the brain's striatum region had a detrimental effect on time perception and judgment, opening the door to new therapeutic solutions for mental and neurological conditions such as schizophrenia, Parkinson's and Huntington's diseases, autism spectrum disorder, and Tourette syndrome.
The striatum is responsible for processing and integrating new sensory information from the environment as well as coordinating motor responses. In individuals with mental and neurological disorders, there is often a significant decline in the ability to adapt to changes in the environment and accurately estimate the timing and completion of voluntary actions.
The research, which was just published in the journal Molecular Neurobiology, provided the first evidence for the crucial role cilia play in timing-dependent dysfunction.
Amal Alachkar, Ph.D., corresponding author, and professor of teaching in UCI's Department of Pharmaceutical Sciences, believes his findings will revolutionize our understanding of brain functions and mental disorders in the context of these previously unappreciated organelles in the brain's'central clock,' which operates in a key role.
The striatum is part of the brain's electrical system that performs central clock functions, essential in controlling executive functions such as motor coordination, learning, planning, and attention, as well as acting as a signaling hub that senses and sends signals to generate appropriate responses.
Researchers removed cilia from the striatum of mice using conditional gene manipulation technology. These rodents were unable to learn new motor tasks, displayed repetitive motor behavior, and were deficient in quickly recalling information about their location and orientation in space, as well as in their capacity to filter irrelevant environmental sensory information.
"To have successful functioning of working memory, attention, decision-making, and executive function, you need to have precise timing judgment," Alachkar explained. "When this capacity is harmed, it means losing the ability to quickly adjust behavior in response to external stimuli and failing to sustain appropriate, goal-oriented motor responses."
Wedad Alhassen, Sammy Alhassen, Jiaqi Chen, Roudabeh Vakil Monfared, and Amal Alachkar, doi:10.1115/s12035-022-03095-9, Molecular Neurobiology.
The National Institutes of Health provided funding for the research.