Metacognition and Causal Inference in Audiovisual Speech.

In multisensory environments, our brains perform causal inference to estimate which sources produce specific sensory signals. Decades of research have revealed the dynamics which underlie this process of causal inference for multisensory (audiovisual) signals, including how temporal, spatial, and semantic relationships between stimuli influence the brain's decision about whether to integrate or segregate. However, presently, very little is known about the relationship between metacognition and multisensory integration, and the characteristics of perceptual confidence for audiovisual signals. In this investigation, we ask two questions about the relationship between metacognition and multisensory causal inference: are observers' confidence ratings for judgments about Congruent, McGurk, and Rarely Integrated speech similar, or different? And do confidence judgments distinguish between these three scenarios when the perceived syllable is identical? To answer these questions, 92 online participants completed experiments where on each trial, participants reported which syllable they perceived, and rated confidence in their judgment. Results from Experiment 1 showed that confidence ratings were quite similar across Congruent speech, McGurk speech, and Rarely Integrated speech. In Experiment 2, when the perceived syllable for congruent and McGurk videos was matched, confidence scores were higher for congruent stimuli compared to McGurk stimuli. In Experiment 3, when the perceived syllable was matched between McGurk and Rarely Integrated stimuli, confidence judgments were similar between the two conditions. Together, these results provide evidence of the capacities and limitations of metacognition's ability to distinguish between different sources of multisensory information.

An assessment of critical care capacity in the Gambia.

PURPOSE: Critical illnesses are a major cause of morbidity and mortality in The Gambia, yet national data on critical care capacity is lacking. MATERIALS AND METHODS: We surveyed eight of the eleven government-owned health facilities providing secondary and tertiary care in The Gambia's public health sector. At each hospital, a designated respondent completed a questionnaire reporting information on the presence of an intensive care unit, the number of critical care beds where available, monitoring equipment, and the ability to provide basic critical care services at their respective hospitals. RESULTS: The response rate was 88% (7/8 hospitals). Only one hospital had a dedicated intensive care unit with eight ICU beds, resulting in an estimated 0.4 ICU beds/100,000 population in the country. All hospitals reported treating more than 50 critically ill patients a month, with trauma, obstetric emergencies, hypertensive emergencies and stroke accounting for the leading causes of admission respectively. The country lacks any trained specialists and resources to diagnose and treat critically ill patients. CONCLUSIONS: The Gambia has a very low ICU bed capacity and lacks the human resources and equipment necessary to diagnose and treat the large number of critically ill patients admitted to public hospitals in the country.