Why do people misunderstand stroke symptoms? How background knowledge affects causal attributions for ambiguous...

Primary objective: People often misattribute stroke survivors' symptoms to other causes such as their personality, especially when the survivors are young. As a result, these stroke survivors experience feelings of resentment towards and from their acquaintances, and may struggle to retain employment. This study aimed to clarify how people's misattributions for stroke symptoms were affected by varying information about the stroke. Methods: Experiment 1 examined whether the stroke survivor's age (72, 32 or unstated) and the information about the person's stroke (no information, explicit stroke or implied stroke) influenced participants' causal attributions for the stroke survivor's four ambiguous symptoms, such as fatigue. Experiment 2 examined the effect of the rapidity (a week or a year) with which the symptoms appeared. Results: When the scenario explicitly referred to stroke, participants attributed the ambiguous symptoms more to stroke, whereas when it did not mention stroke, participants attributed these symptoms more to other factors. When stroke was merely implied by reference to unilateral paralysis, participants rated stroke the best explanation when the target person was 72 but not when he was 32. Experiment 2 showed that stating that the symptoms happened rapidly heightened attributions to stroke in the 72-year-old but not the 32-year-old. Conclusions: These findings show how different information about stroke survivors affect people's attributions for survivors' behaviour; this has important implications for accurate diagnosis and effective rehabilitation that targets these attributions.