Decisional capacity in a clinical context refers to a person's ability to make a specific decision at the time it needs to be made. This includes understanding relevant information about the decision, retaining that information, using or weighing that information as part of the decision-making process, and communicating their decision by any means. It is decision-specific and can fluctuate over time depending on factors such as consciousness, emotional state, or intoxication. The Mental Capacity Act 2005 presumes capacity in adults unless proven otherwise and emphasizes supporting the person to maximize their decision-making ability before concluding incapacity. The assessment focuses on whether an impairment or disturbance in the mind or brain prevents the person from making the decision, not on the perceived wisdom of the decision itself NICE CKS,NICE NG108,NICE CKS.
Executive capacity, on the other hand, relates to the mental processes known as executive functions, which are involved in planning, organizing, sequencing, and completing tasks that require multiple steps or decisions. Executive dysfunction occurs when these processes are impaired due to brain injury, illness, or developmental issues, leading to difficulties in everyday planning and decision-making. This dysfunction can be subtle and may not be detected by standard clinical tests, often requiring real-world observation to assess the person's ability to function and make decisions effectively NICE NG108.
In summary, decisional capacity is about the ability to make a particular decision at a specific time, focusing on understanding and processing information relevant to that decision. Executive capacity involves broader cognitive abilities required to carry out complex, multi-step tasks and manage daily functioning. While decisional capacity is legally defined and assessed under the Mental Capacity Act, executive capacity refers to cognitive functions that support decision-making and task completion but may require different assessment approaches NICE CKS,NICE NG108,NICE CKS.