Increased Use-Dependent Plasticity With Chronic Insomnia
(HealthDay News) — People with chronic insomnia (CI) have increased use-dependent plasticity (UDP) relative to age-matched good sleepers, according to a study published in the March issue of SLEEP.
Noting that UDP can be used to assess neuroplasticity in the context of motor training, Rachel E. Salas, MD, from the Johns Hopkins Medical Institution in Baltimore, and colleagues evaluated the ability of patients with CI and age-matched good sleeper controls to undergo UDP using a well-established transcranial magnetic stimulation paradigm. The effect of insomnia on intracortical motor excitability measures was also assessed.
The researchers found that increased UDP changes were experienced by patients with CI compared with controls. Differences in motor training did not contribute to this effect. Furthermore, in the absence of changes to intracortical inhibitory measures, patients with CI exhibited enhanced intracortical facilitation compared with controls.
"This suggests a heightened state of neuroplasticity, which may reflect a form of maladaptive plasticity, similar to what has been described in dystonia patients and chronic phantom pain after amputation," the authors write.