Ana's mother is 85 years old. It has been some time since her children noticed she was absent minded but they thought it was something normal for her age. She used to forget the food on the stove and therefore bought a watch that had a bell that warned her when the time was ready. She started to write down all the things she had to buy as well as telephone numbers, something that she managed before without any difficulties.
Additionally, during the last year she had stopped wanting her friends to visit her. They had used to drink coffee together and chat until dusk. They had played cards and simultaneously talked about their lives and the lives of their families and friends.
Lately, it has proved very difficult for her to follow a conversation. She does not know how to participate in what for her is an authentic thunder of sounds, smiles, looks, and references to past histories through subtle jokes with a double meaning... a real problem. According to her, her friends are now strange, talk in codes and they lie. It is no longer possible to trust them.
"They say that Paca is beautiful with her new hairstyle when she actually looks really horrible (those highlights really do not seem suitable for her age), and I told her. They all felt bad but what did they think? It is nothing but true."
Teresa, Ana's mother was very good at playing card-games. She was clever in bluffing, cheating, winking and now... they catch all her tricks. "Are you silly?" Her habitual game partner cries.
When she is alone, she even starts to think they are right. Nothing is like as it was before. Sometimes, her daughter notices her crying, so she tells her: "Don't be so occupied with yourself! At the end of the day you are 85 years old." - With all the problems I have at work, with the children, the house, etc. and she only thinks about herself. She has turned very selfish - thought Ana.
Last week her sister had an appendicitis operation and was close to death, but Teresa was immersed in her own business. She was not bothered. Her sisters discussed the operation in her presence, worried and even cried. She showed no response. Any feelings shown by others are distant to her. When they explained to her in detail what was happening and the risk her sister's life was in, she started to cry. It is as if she understands things late. Anyway, she recovered her composure very soon.
Ana still remembers, just a year ago, how her mother asked her immediately as she saw her: "What has happened between you and Paco?" It is true that I had the eyes red of crying but the question surprised me. Teresa continued: "I saw how you looked at each other and I did not like it at all..." Today, she would not detect such a thing. Not even if I cried in her face, she would not ask me what was going on - Ana stated regretfully. Her mother had become naïve. She was no longer aware of the ins and outs of the family. She only understands conversations if they are directly addressed to her. The other things: the double meanings, the lies, the half-truths, the white lies, the bluffs, the jokes, etc. they have no meaning for her. She does not get them anymore. As her friend says: "she is silly!" She has a superficial smile on her face that does not transmit anything. Even when she cries it seems without conviction. Other people of her age are not like this although having memory problems as well. Ana is not sure about taking her mother to the doctor. Despite everything, she continues to do all the domestic chores in the house (she uses certain strategies to help her not to forget), going to church, getting her pension and handling the Euros (with occasional mistakes) etc. Her doctor says that nothing is wrong, only the usual memory loss that goes with her age but he does not know her. He is a new practitioner. If it only had been Dr. Lorenzo who had seen her, her old doctor, he would have realized her strange behaviour.
The main character of this story was diagnosed with the Alzheimer disease a year later. Two years after that she did not recognise her grandchildren and thought her daughter was her mother.
Certain patients with dementia develop a kind of mental block for reading social situations. They have difficulties in understanding some double meanings, white lies (like the one about the hear of Teresa's friend) and the jokes. For them the language is just used for transmitting information, which means that they do not enjoy talking merely for the sake of talking. Some patients also lessen their repertoire of gestures. They easily laugh, make gestures of anger or sadness, but they do not easily understand other people's complex gestures, as for instance, a sportsman's scream of joy after having won a race. This deficit has been described in patients with autistic spectrum disorders in the Theory of mind. They seem to be related to the alternations taking place in the longest brain connections that link associated areas. These areas show a predominating cholinergic transmission, which early affects the Alzheimer disease. On the other hand, the pathology of Alzheimer begins in the tonsil and hippocampus progressing forward towards the orbit frontal cortex and from behind towards the posterior cingulum. Researches with PET have shown that the posterior cingulum and orbit frontal cortex are activated when working with tasks related to the Theory of mind. It seems then reasonable that these functions are altered in the case of the Alzheimer disease. The impression that the doctors have from observing these patients, in accordance with their families as well, is that these alterations in the process of the social information appear early in the majority of the Alzheimer patients.
Perhaps the study of these alterations leads to an earlier diagnosis of this disease. It could even help us to differentiate the mild cognitive deterioration, of amnesiac type, that later will evolve in the Alzheimer disease and from those that will not evolve towards it. We need to develop tools that can measure in an objective way this kind of deficit and to include them as a routine in the study of these patients. Furthermore, the patient's quality of life and of their families will possibly improve with cognitive stimulation of these functions in memory workshops.

Juan Marín Muñoz
Neurologist Dementia Unit HUVA