That pain could be in your head

The central nervous system may play an important role in a syndrome involving chronic pain

The choroid plexus is a network of cells lining the inside’s of the brain’s ventricles (pictured above) / Wiki Commons

Neuroscientists have found a connection between the size of the choroid plexus (a network of cells found lining the cavities of the brain and the spinal cord), and complex regional pain syndrome (CRPS), a kind of chronic pain that begins with a minor area in the periphery and slowly spreading outwards.

The findings of researchers from Aalto University, in collaboration with researchers at Helsinki University Hospital and Harvard Medical School, were recently published in the Scientific Reports online journal.

‘When studying magnetic resonance images of the brains of patients suffering from CRPS, we noticed that the choroid plexus was nearly one-fifth larger in patients than in healthy control subjects,’ says postdoctoral researcher Guangyu Zhou from Aalto University Department of Neuroscience and Biomedical Engineering, who analyzed the images.

The choroid plexus is best known for producing cerebrospinal fluid, which forms a protective mechanical cushion and immunological buffer for the brain. It also controls the passage of many substances from the blood into the cerebrospinal fluid, brain, and spinal cord.

It also secretes into the cerebrospinal fluid many proteins and other signaling substances involved in the growth and maintenance of the brain. It also allows immune system cells to enter the brain, suggesting that could be a link between the peripheral and central inflammatory systems

According to Professor Hari, ‘In clinical neuroscience, the functions of choroid plexus beyond cerebrospinal fluid generation have been largely neglected; for example, the size of the choroid plexus is not quantified in routine brain scans.’

Regional pain syndrome is a chronic and highly debilitating condition that typically develops after a minor trauma, to the hand for example, and then spreads to other areas, such as the whole upper limb and sometimes even to the other side of the body. Thus, it has been suggested earlier that the central nervous system might play an important role in the disease.

The scientists measured the volume of the choroid plexus in 32 people, 16 of who were CRPS patients, using structural magnetic resonance images.

The research was funded by the Academy of Finland, European Research Council and Tekes – the Finnish Funding Agency for Innovation.

This is based on a release from Aalto University and the article in Scientific Reports