ABSTRACT
The incidence of ischemic stroke (IS) is rising in tandem with the global aging population. There is an urgent need to delve deeper into the pathological mechanisms and develop new neuroprotective strategies. In the present review, we discuss the latest advancements and research on various nanodrug delivery systems (NDDSs) for targeting microglial polarization in IS treatment. Furthermore, we critically discuss the different strategies. NDDSs have demonstrated exceptional qualities to effectively permeate the blood-brain barrier, aggregate at the site of ischemic injury, and target specific cell types within the brain when appropriately modified. Consequently, NDDSs have considerable potential for reshaping the polarization phenotype of microglia and could be a prospective therapeutic strategy for IS. The treatment of IS remains a challenge. However, this review provides a new perspective on neuro-nanomedicine for IS therapies centered on microglial polarization, thereby inspiring new research ideas and directions.
ABSTRACT
BACKGROUND: In the classical psychological refractory period (PRP) paradigm, two stimuli are presented in brief succession, and participants are asked to make separate speeded responses to both stimuli. Due to a central cognitive bottleneck, responses to the second stimulus are delayed, especially at short stimulus-onset asynchrony (SOA) between the two stimuli. Although the mechanisms of dual-task interference in the classical PRP paradigm have been extensively investigated, specific mechanisms underlying the cross-modal PRP paradigm are not well understood. In particular, it remains unknown whether the dominance of vision over audition manifests in the cross-modal PRP tasks. The present study aimed to investigate whether the visual dominance effect manifests in the cross-modal PRP paradigm. METHODS: We adapted the classical PRP paradigm by manipulating the order of a visual and an auditory task: the visual task could either precede the auditory task or vice versa, at either short or long SOAs. Twenty-five healthy participants took part in Experiment 1, and thirty-three new participants took part in Experiment 2. Reaction time and accuracy data were calculated and further analyzed by repeated-measures analysis of variance. RESULTS: The results showed that visual precedence in the Visual-Auditory condition caused larger impairments to the subsequent auditory processing than vice versa in the Auditory-Visual condition: a larger delay of second response was revealed in the Visual-Auditory condition (135 ± 10 ms) than the Auditory-Visual condition (88 ± 9 ms). This effect was found only at the short SOAs under the existence of the central bottleneck, but not at the long SOAs. Moreover, this effect occurred both when the single visual and the single auditory task were of equal difficulty in Experiment 1 and when the single auditory task was more difficult than the single visual task in Experiment 2. CONCLUSION: Results of the two experiments suggested that the visual dominance effect occurred under the central bottleneck of cognitive processing.
