Posted by alexandra_k on December 21, 2004, at 18:02:58
The Nature of Anomalous Experience.
Maher is primarily interested in enumerating the kinds of anomalous experience that are relevant to the explanation of schizophrenic delusions, rather than explaining the delusions of misidentification that typically arise from cerebral trauma that are the focus of Davies et al.’s battery. He does, however, state that:
>[D]elusional interpretations of circumscribed anomalies of experience arising from psychopathology are not confined to schizophrenia. . . .[T]he model of delusion formation . . . posits that the basic origin lies in the anomalous experience, regardless of how that anomaly arose (Maher 1999, p.566).
As such, we should expect that his account would be capable of explaining each of the delusions presented in Davies et al’s battery. Maher explicitly considers six kinds of schizophrenic anomalous experience while acknowledging that there might be others. The one that would seem most relevant to an explanation of the Capgras delusion is considered to be ‘feelings of non-recognition’ which consists in ‘unrecognized defects in the sensory system… or the endogenous activation or inhibition of the central neural representations of sensory input’ (Maher, 1999 pp. 553-554). Maher does not explicitly consider Ellis and Young’s model of face recognition, and the possible implications of the physiological findings for the nature of the experience of subjects who develop the Capgras delusion in response to cerebral trauma, though to be fair he is more focused on accounting for schizophrenic delusions. Davies et al. (2002, p. 143) firstly consider that the nature of the relevant anomalous experience may be an ‘unusual experience of faces or a sense that “something is different” as a result of flattened affective responses’. This line may be seen as being similar to Maher’s, though more explicit.It may be the case that if the specification of the content of the anomalous experience is as general as the above accounts then there is indeed a difficulty in getting from such a vague or general experience to the sorts of utterances that are characteristic of the Capgras and Frégoli delusions. There does not seem to be anything intrinsic to the nature of the anomalous experience to determine that the subject must develop a delusion in the face of such an experience. As such Davies et al. would seem to be correct in considering that a second factor must be required in addition to the anomalous experience to account for why some subjects develop delusions in the face of such an experience while others do not.
Maher considers that the crucial difference between delusional and non-delusional subjects is that while a non-delusional subject may have fleeting or transitory anomalous experiences these are comparatively shallow compared with the intensity and duration of the delusional subject’s anomalous experience. Maher’s appeal to intensity and duration has come under fire by theorists who maintain that there is no independent way in which to cash out the intensity and duration clause without reference to whether the subject is delusional or not. Whether this is able to be cashed out or not would seem to be an empirical matter, however, and we may consider skin galvanization response to be such an independent measure (though see Breen et al. (2000) for a criticism of the significance of these findings). What I wish to consider here is that once the nature of the anomalous experience is suitably refined the nature of the experience may turn out to be more significant for the production of delusion than intensity and duration.
poster:alexandra_k
thread:432572
URL: http://www.dr-bob.org/babble/write/20041210/msgs/432572.html