Brain Function in Familial ALS

Dr Matthew Kiernan

Cortical hyperexcitability is a known hallmark of ALS, and the potential for cortical hyperexcitability, according to Prof. Kiernan, is something we are all born with. “We know that newborns, in their first few weeks of life, have more excitatory pathways in their brains,” Prof. Kiernan says. “Gradually, within the course of a few months, this changes. The process is not very well understood at a biological level, but the brain switches from an excitatory brain to an inhibitory brain. Subsequently, when ALS manifests, patients experience another switch from inhibitory back to excitatory. The disease seems to be, in some way, reactivating these pathways.” Over time, this hyperexcitability becomes permanent, leading to neuron death and loss of muscle function in patients with ALS.