This is a map of repetition among all symptoms in the DSM-5.
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These findings are from a descriptive study published in Psychological Medicine which mapped the repetition among the 1419 symptoms described in 202 diagnoses of adult psychopathology in section II of the DSM-5. 2/10 cambridge.org/core/journals/…
The first stage of coding aimed to distil the constituent symptoms of the diagnoses in chapters 1–19 of section II of the DSM-5. The resulting list of symptoms was then coded for content overlap using both qualitative content coding and natural language processing. 3/10
In total, 202 diagnoses were represented, including 135 primary disorders and 76 specifiers or other specified disorders with additional symptoms. While repetition appeared to be pervasive, the majority (63.2%) of the 628 distinct symptoms were unique to a single diagnosis. 4/10
Overall, of the 202 diagnoses represented, 140 (69.3%) had at least one symptom that repeated in another diagnosis – 118 (58.4%) in a diagnosis in another chapter. 5/10
A noteworthy finding was that the symptoms in the DSM-5 that repeat most frequently, and that repeat across most chapters, are dominated by symptoms of major depressive disorder (MDD). 6/10
Specifically, 10 of the top 15 most non-specific symptoms in the DSM-5 appeared in the diagnostic criteria for MDD. 7/10
Perhaps MDD symptoms are psychological responses to stress, similar to how fever – a symptom that also cuts across numerous diagnostic categories – reflects an inflammatory response to cell damage or stress. 8/10
The pervasiveness of MDD symptoms throughout the DSM-5 likely hampers diagnostic accuracy through misattribution of symptoms in other diagnoses to MDD, and inflation of the rates of comorbidity due to symptom overlap with other diagnoses. 9/10
Ultimately, more empirical work on fine-grained clinical phenomena promises to improve on the reliability and validity of the DSM-5 constructs that frame much research and practice. 10/10
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Our paper was just published in the British Journal of Sports Medicine.
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Recent studies have demonstrated that exercise has antidepressant effects comparable to those of medications or therapy, with simultaneous multisystem benefits to one’s physical health. 2/10
Exercise has been adopted as a first-line treatment in guidelines for depression globally, however, clinically, exercise is uncommonly prescribed or prioritised in the psychiatric setting. 3/10
Antidepressant efficacy is inflated by the cumulative impact of publication bias, outcome reporting bias, spin, and citation bias on the evidence base.
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This discussion is from a paper in @CambUP_Psych which analyzed the cumulative impact of biases on apparent efficacy for antidepressants. 2/12 cambridge.org/core/journals/…
Publication bias is the failure to publish the results of a study on the basis of the direction or strength of the study findings; oftentimes, studies which have statistically significant positive results get published and the negative studies do not. 3/12
Our paper was just published in the Journal of Psychiatry & Brain Science.
5 grams of creatine per day saturates your muscles, but is likely too low for the brain.
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Given the constant energy supply required by the brain, there has been increasing interest in the potential of creatine for improving brain bioenergetics, health and function. 2/10
Accumulating research indicates that creatine is capable of increasing brain creatine stores which may help explain improvements in cognitive functioning particularly during times of metabolic stress. 3/10
Stronger legs are associated with larger brain volume & slower cognitive decline.
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These findings are from a study in @KargerPublisher which tested whether muscle fitness (measured by leg power) could predict cognitive change in a healthy older population over a 10-year time interval. 2/7 karger.com/ger/article/62…
There is consistent evidence from observational studies of a protective association between levels of physical activity and subsequent cognitive ageing within the healthy population. 3/7
A common belief is that cognition arises from the brain.
This paper suggests that cognition is a complex multiscale information processing distributed across every single cell in the body.
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These findings are from a paper in @FrontNeurosci which argues that a promising way forward in understanding the nature of human cognition is to zoom out from the prevailing picture focusing on its neural basis. 2/10 frontiersin.org/journals/integ…
The idea that the mind is distinct from the body and somehow at home in the human brain has deep roots in a longstanding philosophical and scientific thinking, stretching from antiquity to the present day. 3/10