To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The National Institute of Mental Health launched the Research Domain Criteria (RDoC) initiative to better understand dimensions of behavior and identify targets for treatment. Examining dimensions across psychiatric illnesses has proven challenging, as reliable behavioral paradigms that are known to engage specific neural circuits and translate across diagnostic populations are scarce. Delay discounting paradigms seem to be an exception: they are useful for understanding links between neural systems and behavior in healthy individuals, with potential for assessing how these mechanisms go awry in psychiatric illnesses. This article reviews relevant literature on delay discounting (or the rate at which the value of a reward decreases as the delay to receipt increases) in humans, including methods for examining it, its putative neural mechanisms, and its application in psychiatric research. There exist rigorous and reproducible paradigms to evaluate delay discounting, standard methods for calculating discount rate, and known neural systems probed by these paradigms. Abnormalities in discounting have been associated with psychopathology ranging from addiction (with steep discount rates indicating relative preference for immediate rewards) to anorexia nervosa (with shallow discount rates indicating preference for future rewards). The latest research suggests that delay discounting can be manipulated in the laboratory. Extensively studied in cognitive neuroscience, delay discounting assesses a dimension of behavior that is important for decision-making and is linked to neural substrates and to psychopathology. The question now is whether manipulating delay discounting can yield clinically significant changes in behavior that promote health. If so, then delay discounting could deliver on the RDoC promise.
Many factors influence the development of body image, one of which is the perception we have of our body. Perception can refer to actual visual input or the interpretation of vision; in other words, cognitive appraisal. The goal of this preliminary study is to determine if three groups (body dysmorphic disorder, obsessive-compulsive disorder, and a non-psychiatric control group) differed in the perception of their faces. Thirty individuals, 10 in each group, were asked to make changes to a computerized image of their face. In addition, affective and perceptual tests were administered. The groups did not differ on affective and perceptual organizational measures, although the obsessive-compulsive disorder group reported a higher level of anxiety than the body dysmorphic disorder group. Imaging software showed that facial features were modified by patients with body dysmorphic disorder and obsessive-compulsive disorder in about 50% of cases. No modifications were made in the control group. Future studies need to investigate the possible causes of these differences.
This chapter identifies clinically meaningful subtypes of obsessive-compulsive disorder (OCD) including discrete categories based on age of onset and comorbidity with related disorders, and then describes efforts to understand obsessive-compulsive (OC) symptoms as dimensions. Both categorical and dimensional approaches have been applied in research on refining the phenotype of OCD. A strategy that has been successfully applied to other heterogeneous and complex psychiatric disorders is to identify intermediate phenotypes that are more closely related to neurobiological mechanisms than phenotypes. Modern neuroimaging techniques have allowed abnormalities in white-matter brain tissue to be investigated as potential OCD endophenotypes. Subtypes of OCD have been proposed, based on early age of onset, tic comorbidity, and obsessive-compulsive personality disorder (OCPD) comorbidity. Another approach to deconstructing the heterogeneity of OCD is the identification of vulnerability markers or endophenotypes. Integrating phenotypical and endophenotypical approaches may be fruitful in advancing the field.
Recommend this
Email your librarian or administrator to recommend adding this to your organisation's collection.