Final answer:
The statement is true; attention impairment is a primary feature of delirium, characterized by an inability to maintain focus during conversation or perform tasks that require attention such as reciting the months or days of the week in reverse order.
Step-by-step explanation:
True - A hallmark of delirium is indeed the impairment of attention. The statement that a person with delirium is unable to focus on a conversation, cannot pay attention, and may have difficulty reciting the months or the days of the week backwards reflects the difficulties someone may experience with orientation and working memory. These symptoms must be distinguished from similar symptoms that could occur in diseases like Alzheimer's disease. Importance is also placed on correct evaluation because conditions like Alzheimer's include symptoms such as disruptive memory loss, confusion about time or place, and difficulty with planning and executing tasks.
In the context of memory and cognitive assessments, tasks such as the three-word recall test, reciting the months of the year in reverse order, and spelling common words backwards are used to more accurately gauge memory function beyond simple orientation. These tests help to avoid relying on overlearned sequences and focus assessments on the ability to recall and manipulate information in working memory.