There are many reasons why a person might have difficulty in preparing a meal. Usually, the problem is not one of forgetting how to mix ingredients, or stir a pot or break an egg. These are very highly learned motor behaviours that are known as procedural memory Procedural memory
Memory of skills and abilities that cannot be described in words. , and which often will be well preserved. Many people with severe dementia can still complete single-task chores. Instead, in mild dementia, people lack the motivation to start the task, or the insight to know that it is time to get started, or the ability to plan, or the judgment to choose what should be served. They can also have difficulty remembering which things on the list have already been done.

These complex behaviours often reflect more problems with planning, sequencing, insight and judgment, which are known as executive function Executive function
Includes the behaviors associated with judgment, agitation and social behavior - not memory. These behaviors are affected in all dementias, but especially in frontotemporal dementia.. Such functions are importantly dependent on the frontal lobes (regions in the front part of the brain). We know that because people who have localized damage to their frontal lobes (say from a car accident, bullet, tumor Tumor
An abnormal mass of tissue that is the result of excessive cell division. They are not useful to the body and can be benign (non-cancerous) or malignant (cancerous). or blood vessel problem) characteristically have problems with executive function. Frontal lobe impairment was classically seen as a late sign Sign
In medicine a sign is what a physician finds by examining a patient. For example, a patient with the symptom of pain might have signs of a fast heart rate, a pale face, a clammy touch and tenderness. of Alzheimer's disease Alzheimer's disease
A neurological disease that affects memory and behaviour. It is characterized by beta-amyloid plaques and neurofibrillary tangles in the brain. There is no known cause but genetics and lifestyle are thought to play a role., but thinking about this has changed in two ways. Now that there is better testing of the frontal lobes, we see that there is involvement early in the disease. Also, brain imaging studies suggest that early on, the brain is able to compensate for damage in the frontal lobes, but the ability to compensate becomes less as the disease progresses. This is an important insight, because it suggests that strategies to treat Alzheimer's disease should not just focus on countering the disease process, but also should enhance the repair process.


This issue is explored in considerable detail in the chapter on "Executive Function" by Sarah Voss and Roger Bullock, in the book Trial Designs and Outcomes in Dementia Therapeutic Research, published in London by Taylor & Francis, 2005, and edited Kenneth Rockwood and Serge Gauthier. The assessment of function in anti-dementia drug trials is discussed in detail in another chapter in that book, by Serge Gauthier.