[MUSIC] The description of the content of thought in the mental state examination poses a number of challenges. It is here where we draw heaving on the legacy of Karl Jasper's thinking. The task of describing thought content in the mental state examination is not simply a restatement of the history given. The intent is to capture what is thought and the mode in which it is thought. At it's simplest, the thought content can be described as a spectrum of intensity in conviction of thought ranging from normal responses to questions asked, to the observations and themes and perhaps pre-occupations that the patients recurrently returns to. An example in depressed patients is the tendency to endorse the negative aspects of the self in the world. As we move further to the right of the intensity conviction spectrum, we come to what Jasper's called overvalued ideas. The content is often understandable or comprehensible by the interviewer, but the intensity is beyond what would be expected by the available evidence. These thoughts preoccupy the patient who has a strong emotional investment in the thought. There are passionately held, but with challenge, can be somewhat amenable to reasoning. The task of the interviewer is to challenge the basis of the thought in order to determine the conviction with which is held. Overvalued ideas need to be differentiated from dillusions proper which are the most intensely held of beliefs. Delusions are the quintessential manifestation of thought content abnormality. Jaspers emphasize that what makes the thought delusional is the way it is thought and constituted, rather than what is actually thought. This is the distinction between the form of the thinking, rather than the content or subject of the thought. Drawing on some of Jasper's insights, a number of features related to the form of the thinking are usually advanced as evidence for a delusional thought. Delusional thoughts are said to be fixed and unshakeable and held with absolute conviction. Despite challenged by the interviewer, the delusional patient marshalls all the cognitive forces in the defense of the belief. Furthermore, delusional beliefs are not just any old passing thought, but have great, personal significance for the patient. Preoccupy them and they invest themselves in the belief. As such, delusions are pre-eminent in the patient's thinking. It is often said that delusions are considered false or inherently unlikely by others and out of keeping with the patient's educational, cultural or social background. This however can be difficult to judge in certain individual cases. These rules may not always be sufficient in themselves to define a delusion. As Paul Mullen noted in 2008, many so-called normal beliefs, may fit into these rules. Furthermore, these rules do not account for the rare circumstances that sometimes delusional beliefs can also be true. Mullen felt that further defining features were helpful in determining delusional thinking. These include the emergence of the delusional beliefs in a pathological manner, that is, the evidence put forward for the belief contains idiosyncracies and bizarre logic. In addition, delusional beliefs has a way of contaminating a broad range of other beliefs about the world, so the patient constitutes the world in the service of the delusion. Jaspers differentiated primary delusions from secondary delusions or delusional-like ideas. In his view, primary delusions arise de novo, that is, without precedent or what he turned understandability. In this way, primary delusions were not psychologically reducible to pre-existing experience or thought. Common examples described by Jaspers, are one, the sudden, autochthonous delusion. Here, there's a new delusional belief arising suddenly and out of the blue. Number two, delusional atmosphere is usually an insidious onset belief that something momentous usually threatening or catastrophic is going to happen. The patient is increasingly intensely preoccupied by the thought and what is often most frightening is the lack of clarity for the patient about exactly what is going to happen. This delusion is frequently accompanied by the affect of perplexity. Number three, delusional perception, is where a new belief forms in the context of a seemingly mundane, but normal perception. The relationship between the perception and the delusion is frequently not understandable. and number four, delusional memory is a sudden onset new memory that can come to the patient as a revelation or new understanding of their own history. Sometimes it can be difficult to discount the memory, unless it is bizarre or historically impossible. Secondary delusions according to Jaspers arise understandably from other psychic events. They maybe traced understandably to primary delusions, affects and hallucinations and so are considered more psychologically reducible to other primary drivers. Secondary delusions are more amenable to psychological exploration of their origins and meaningful understanding and have a form closer to overvalued ideas. Following effective treatment, there can be seen a retreat in the intensity and preoccupation by the patient from fixed delusional thinking to overvalued ideas and beyond. The phase of the patient's illness is therefore critical in understanding the thought content. While Jaspers emphasised the role of abnormality of form of thinking in delusions, the content is also important to describe, as this is frequently a driver of the patient's behaviour and distress. The extent to which the content can be meaningfully analyzed and understood is frequently debated, however, this is not the task of the mental state examination. While the content of delusional thoughts is endless in it's possibility, common groupings are noted. The first distinction is between bizarre delusions where the content is fantastic and beyond even broad human experience and non-bizarre delusions. This latter group contains a number of commonly held delusional beliefs. This includes persecutory delusions, delusions of passion including jealousy, love and entitlement, delusions of identity related either to the self identity which is often grandiose, or the identity of others, including Capgras and Fregoli delusions. Delusions of reference, where the world is seeing as referring specifically to the patient. Delusions of the body, which can include hypochondriacal delusions, somatic delusions and delusions of non-existence. Delusions may also be seen in the affective domain. In elderly patients with psychotic depression, there can be delusions of guilt, poverty, worthlessness or failure. In the manic patients, there may be delusions of extraordinary talent, knowledge, power and identity. Delusions may also involve the patient's sense of control. Delusions of thought possession occur when the patient believes there is a loss of control of the integrity of their thoughts and can include the insertion or withdrawal of thoughts by others, or the controlling of patient's thoughts by others. A related group of delusions is sometimes called passivity phenomena, where the patient believes critical aspects of their personal control such as thoughts, feelings and actions, are assumed by another entity. Delusions must be distinguished from other types of intrusive thoughts. One of the most important of these is the obsessional thought characteristic of an obsessive compulsive disorder. Obsessional thoughts are recurrent, intrusive thoughts, but also images and impulses that are distressing to the patient which is so called ego dystonic. They are generally recognised as abnormal by the patient, but always unwanted and particularly in the early phase of illness, resistant. Patients recognise that the obsessional thought is a product of their own mind. In chronic cases of OCD, there maybe the loss of resistance to the instrusive nature of the thinking which can then be difficult to distinguish from delusions. Obsessional thoughts in OCD are often paired with compulsive behaviours enacted to reduce the distress of the thought. The relief is usually only short lived and may perpetuate the obsessional thinking. Obsessional-like ideas without the full features of an obsessional thought, are also seen in depression, such as, intrusive thoughts of guilt and failure, and bodily thoughts found in eating disorders and body dysmorphic disorders.
