Culture, depression, and somatization: A tale of two paradigms

Decades of cross-cultural research have documented a distinctive form of psychopathology among depressed non-western patient populations characterized by a number of somatic symptoms such as headache and gastrointestinal discomfort in response to psychological distress. This symptom profile is known as somatization. The presence of somatization among non-western patients differs from western concepts of depression where psychological symptoms (e.g. sad mood) are more prevalent in response to psychological distress. This distinct difference in the clinical presentation of depression among non-western and western patients highlights a critical issue regarding the utility of current diagnostic practices across cultures. For example, researchers have argued that contemporary diagnostic practices based on a traditional classification system are founded on a western biomedical model of illness that reduces genuine psychopathology to underlying physiological mechanisms. Under this model, psychopathology is universal. However, there is evidence to suggest that psychopathology may be relative to culture. These arguments highlight two fundamental paradigms—universalist and relativist—which are relevant to understanding the presence of somatization among non-western patients experiencing psychological distress. According to the universalist paradigm, people experience the same psychopathology after cultural influences are accounted for, regardless of culture. Following this assumption, the somatic symptoms reported by non-western depressed patients are merely the result of cultural values and when accounted for, these patients exhibit the same psychopathology as those in the western cultures. In contrast, the relativist paradigm asserts that psychopathology is woven within the fabric of culture. Beliefs, rituals, and other cultural influences affect the phenomenology of psychopathology. Thus, under the relativist paradigm somatization may represent a culture-bound illness that is qualitatively different from depression as experienced in western cultures. Allegiance to either the universalist or relativist paradigms has important implications for research, treatment, and diagnosis. For example, proponents of the universalist paradigm may be inclined to offer a conventional treatment for depression to a non-western patient presenting with somatic symptoms in conjunction with psychological distress because the somatic complaints are essentially a product of the patient’s culture. On the other hand, those ascribing to the relativist perspective may be inclined to treat a non-western patient who exhibits the same symptoms with a therapy that is based on the value systems within the patient’s cultural context. Given the implications of each paradigm this paper reviews the dialogue surrounding three prevalent explanatory models pertaining to non-western somatization—assessment modality, alexithymia, and language—within the context of each paradigm. I argue that the explanations provided by research investigating the effects of assessment modality and alexithymia on somatization among non-western depressed patients are dominated by the universalist paradigm. Regarding the literature surrounding the role language plays in understanding somatization and the psychopathology of depression, a number of researchers offer compelling evidence in support of the relativist paradigm. Paradigms play a critical role in understanding the nature of psychopathology. Therefore, researchers and clinicians working with diverse patient populations need to consider the implications of their allegiance to either paradigm. Suggestions are offered for future research on the topic of somatization among non-western patients

An Investigation of the Effects of Depressive-Rumination on Prospective Memory

Depression is related to prospective memory (PM) impairment. However, the research on depression-related PM impairment remains inconclusive. No study to date has taken into account the possible effects of depressive-rumination, which is known to impair executive functions underlying PM. The current study addresses this gap in the literature. Participants: Participants were grouped according to self-reported depression severity per the Beck Depression Inventory-Second Edition (BDI-II). Fifty-five individuals with low (BDI-II \u3c 8), 17 individuals with moderate (BDI-II 9-18), and 16 individuals with high (BDI-II \u3e 19) symptoms of depression were included in the study. Method: Participants completed demographic and trait and state rumination questionnaires. Participants within each group were then randomly assigned to either a rumination or distraction condition. Following this manipulation, participants completed a modified version of the Memory for Intentions Test. Results: Regardless of depression severity, inducted state rumination had no effect on PM. In addition, depression severity was unrelated to both event- and time-based PM trials, and overall PM performance. Interestingly, trait rumination was negatively correlated with overall PM performance in the low group compared to the moderate group, wherein trait rumination was positively correlated with overall PM performance. Trait rumination was not correlated with overall PM performance in the high depressive symptom group. Conclusion: The current study failed to demonstrate depression-related PM impairment as a function of depressive-rumination. Furthermore, depression severity had no effect on overall PM performance. The positive correlation between trait rumination and overall PM performance in the moderate group offers some support for the positive benefits of rumination among people experiencing sub-clinical depression proposed by Albiński et al., 2012. Results from the current study should be interpreted with caution given the small sample size and low statistical power. Further research is needed to elucidate the effects of depressive-rumination on PM

OVERGENERAL MEMORY: AN INVESTIGATION OF THE DEFENSIVE EXCLUSION AND FUNCTIONAL AVOIDANCE HYPOTHESES

and PTSD generate overgeneral autobiographical memories. It has been proposed that this phenomenon is the result of functional avoidance—actively avoiding thoughts that would elicit unwanted negative affect. Curiously, the functional avoidance hypothesis of overgeneral memory (OGM) overlaps conceptually with attachment theory’s concept of defensive exclusion. The current study tests whether a model of defensive exclusion predicts the presence of OGM and whether variables underlying the functional avoidance hypothesis (i.e., trauma exposure, PTSD, and depression) account for a significant amount of variance in OGM above and beyond the defensive exclusion model. Threehundred and thirty adults completed an untimed version of the minimal instructions autobiographical memory test (AMT) online, and a series of questionnaires related to cognitive avoidance, depression, PTSD, trauma exposure, and adult attachment. The proportion of categoric memories generated on the AMT represented the construct of OGM in the current study. A significant positive correlation was found between cognitive avoidance and the proportion of categoric memories on the AMT, indicating that people reporting higher levels of cognitive avoidance also generate more overgeneral categoric memories on the AMT. Contrary to expectations, attachment avoidance did not moderate the relationship between cognitive avoidance and OGM nor did this interaction significantly predict the presence of OGM. In addition, self-reported trauma exposure, PTSD, and depression did not predict the presence of OGM. Consistent with prior research, data indicate that people reporting higher levels of cognitive avoidance also generate more categoric memories on the AMT. Contrary to expectations, adult attachment avoidance did not moderate the relationship between cognitive avoidance and OGM. Further, trauma exposure, PTSD, and depression were unrelated to OGM. Findings are discussed in the context of methodological differences using the AMT

Self-Averaging of Digital MemComputing Machines

Digital MemComputing machines (DMMs) are a new class of computing machines that employ non-quantum dynamical systems with memory to solve combinatorial optimization problems. Here, we show that the time to solution (TTS) of DMMs follows an inverse Gaussian distribution, with the TTS self-averaging with increasing problem size, irrespective of the problem they solve. We provide both an analytical understanding of this phenomenon and numerical evidence by solving instances of the 3-SAT (satisfiability) problem. The self-averaging property of DMMs with problem size implies that they are increasingly insensitive to the detailed features of the instances they solve. This is in sharp contrast to traditional algorithms applied to the same problems, illustrating another advantage of this physics-based approach to computation.Comment: 9 pages, 13 figure

Demonstration of o-Ps detection with a cylindrical array of NaI detectors

Ortho-positronium (o-Ps), the triplet bound state of an electron and positron, is a promising system in which to search for new physics. O-Ps production and detection can be achieved with a tabletop setup, involving a 22Na source, aerogel and a detector. We present our approach to o-Ps detection using the APEX array, which consists of 24 NaI(Tl) bars, arranged cylindrically. Our approach involves tagging on the 1.27 MeV gamma ray, a technique which is used in positron annihilation spectroscopy (PALS) Gidley et al. (2006). We demonstrate the ability to tag with any one of the bars in the array. Using a NaI(Tl) array of high angular coverage (75%) with this technique provides many benefits. This method provides some advantages over tagging on the positron directly insofar as it minimizes the amount of material inside the source holder and simplifies the design of the DAQ. This has potential applications to CP- and CPT-violation searches in o-Ps