The relation between insomnia and depression in the subacute phase after stroke.

Prevalence rates for both depression and insomnia the first year after stroke are around 30%, significantly impacting the prospects of recovery, rehabilitation, and quality of life. Furthermore, the risk of insomnia and depression becoming chronic is high in the subacute phase post-stroke. This cross-sectional observational study investigated whether insomnia and depression are related in the subacute phase post-stroke, using validated instruments.

Serial list linking by macaque monkeys (Macaca mulatta): list property limitations.

Four sophisticated macaque monkeys (Macaca mulatta) learned 6 different, 15-item ordinal lists (via conditional, 2-choice discriminations) as part of a study assessing some properties of serial list memory in monkeys. After assuring that the first 3 lists were well retained, the researchers attempted to link these by training only the 2 end-item pairs that ordered all 45 items into an inclusive series. A 20-day test of possible pairings among these 45 items was then conducted.

Linking of serially ordered lists by macaque monkeys (Macaca mulatta): list position influences.

Five monkeys (Macaca mulatta) were trained on 2 sets of 3 5-item serially ordered lists. Then, each set was either linked or not in a counterbalanced, within-subject design. Linking entailed training on the 2 pairs that ordered the 3 5-item lists into a single overall 15-item series.

Premise-pair training for valid tests of serial list organization in macaques.

This study evaluated the role of several different training procedures on (1) efficiency of acquisition and (2) organizational characteristics of memory for lists that could be serially ordered. Five macaque monkeys were trained via two-choice object discriminations in a formboard apparatus on several five-item-series tasks that provided different levels of intrasession conditionality. Although ease of acquisition differed for subsets of the constituent pairs, concurrent inclusion of the four premise pairs that defined a list required equivalent amounts of training on every task.

Concurrent conditional discrimination tests of transitive inference by macaque monkeys: list linking.

Processing of serial information was assessed by training six macaques on a five-item list of objects arranged into the four conditional pairs, A-B+, B-C+, C-D+, and D-E+. An analogous list (F through J) was similarly trained. Subsequently, both lists were linked by training on E-F+, a pair that provided adjacent elements from each list.