Emotional Components of Pain Perception in Borderline Personality Disorder and Major Depression-A Repetitive Peripheral Magnetic Stimulation (rPMS) Study

Developmental and Momentary Dynamics in the Onset and Maintenance of Nonsuicidal Self-Injurious Behavior and Borderline Personality Disorder

PURPOSE OF REVIEW

Traditional conceptualizations of both nonsuicidal self-injury (NSSI) and borderline personality disorder (BPD) typically rely on static and unidirectional, linear associations between key biopsychosocial vulnerabilities. Instead, we argue that utilizing a complex dynamic systems view of NSSI and BPD will advance the field, as such conceptual models allow for analysis of bottom-up effects for key vulnerabilities on disorder and behavior emergence, as well as top-down effects of the emergent disorder on underlying vulnerabilities.

RECENT FINDINGS

Following the presentation of a novel framework highlighting momentary and developmental dynamics, we explore several advances in the field that exhibit key dynamic qualities or inform dynamic conceptualizations of NSSI and BPD. At the momentary dynamic level, several advances are being made with multimethod and repeated assessment approaches, as well as advanced bidirectional and complex modeling procedures. Additional progress is being made at the developmental dynamic level, although several questions have arisen regarding the problem of onset and subsequent trajectory, particularly with issues such as pain perception and the interplay between interpersonal, emotional, and behavioral symptoms before and after treatment. Self-injury and BPD both exhibit substantial momentary and developmental dynamics in underlying vulnerabilities, including potential variance in momentary dynamics as a function of psychopathological developmental stage (e.g., onset versus maintenance versus recovery). Recent work has highlighted the necessity of utilizing multimodal research to encapsulate a holistic view of the interplay of several vulnerability factors, the developmental importance of assessment timing, and the need to examine the dynamic interplay between affect, behavior, and interpersonal experiences in BPD and/or NSSI. Research also indicated substantial variation in key vulnerability factors at both between- and within-person levels, highlighting the utility of harnessing statistical models that allow for the simultaneous incorporation of numerous variables at both levels and across several time points. As such, by using a complex dynamic systems conceptualization, we can begin to better understand integrated connections between key vulnerabilities, how they collectively interact in the short term, and how changes in the dynamic interplay between vulnerabilities may arise over the long term and with successful treatment.

Precision Medicine in Alzheimer's Disease: Investigating Comorbid Common Biological Substrates in the Rat Model of Amyloid Beta-Induced Toxicity

Alzheimer's disease (AD), one of the most widespread neurodegenerative disorder, is a fatal global burden for the elder population. Although many efforts have been made, the search of a curative therapy is still ongoing. Individuating phenotypic traits that might help in investigating treatment response is of growing interest in AD research. AD is a complex pathology characterized by many comorbidities, such as depression and increased susceptibility to pain perception, leading to postulate that these conditions may rely on common biological substrates yet to be determined. In order to investigate those biological determinants to be associable with phenotypic traits, we used the rat model of amyloid beta-induced toxicity. This established model of early phase of AD is obtained by the intracerebroventricular injection of soluble amyloid beta1-42 (Aβ) peptide 7 days before performing experiments. In this model, we have previously reported increased immobility in the forced swimming test, reduced cortical serotonin levels and subtle alterations in the cognitive domain a depressive-like phenotype associated with subtle alteration in memory processes. In light of evaluating pain perception in this animal model, we performed two different behavioral tests commonly used, such as the paw pressure test and the cold plate test, to analyze mechanical hyperalgesia and thermal allodynia, respectively. Behavioural outcomes confirmed the memory impairment in the social recognition test and, compared to sham, Aβ-injected rats showed an increased selective susceptibility to mechanical but not to thermal stimulus. Behavioural data were then corroborated by neurochemical and biochemical biomarker analyses either at central or peripheral level. Data showed that the peptide injection evoked a significant increase in hypothalamic glutamate, kynurenine and dopamine content, while serotonin levels were reduced. Plasma Cystatin-C, a cysteine protease, was increased while serotonin and melatonin levels were decreased in Aβ-injected rats. Urinary levels paralleled plasma quantifications, indicating that Aβ-induced deficits in pain perception, mood and cognitive domain may also depend on these biomarkers. In conclusion, in the present study, we demonstrated that this animal model can mimic several comorbid conditions typical of the early phase of AD. Therefore, in the perspective of generating novel therapeutic strategies relevant to precision medicine in AD, this animal model and the biomarkers evaluated herein may represent an advantageous approach.