The evidence that cyclic alternating pattern subtypes affect cognitive functioning is very weak

In their recent paper, Ferri et al. [1] examined the relationships between cognitive functioning and three subtypes of the cyclic alternating pattern (CAP) in non-REM sleep. They concluded that ‘‘CAP A1 subtypes are associated with higher [i.e., better] cognitive functioning, whereas CAP A3 subtypes are associated with lower [i.e., poorer] cognitive functioning” (p. 378). For the reasons summarised below, we contend that In their recent paper, Ferri et al. [1] examined the relationships between cognitive functioning and three subtypes of the cyclic alternating pattern (CAP) in non-REM sleep. They concluded that ‘‘CAP A1 subtypes are associated with higher [i.e., better] cognitive functioning, whereas CAP A3 subtypes are associated with lower [i.e., poorer] cognitive functioning” (p. 378). For the reasons summarised below, we contend that this conclusion is not warranted based on the data presented.