Mood regulation in bipolar disorders viewed through the pendulum dynamics concept

Abstract

Bipolar disorders have been characterized by powerful fluctuations of energy, mood, and thinking patterns. Mood episodes (manic or depressive) could be considered as deviations of a psycho-physiological index above or below a conventionally defined value called ‘normothymia’. In the present study, we analyzed the feedback techniques used to suppress the oscillatory activity exhibited on an inverted pendulum device. Subsequently, we examine the degree that this multimodal feedback design could be considered on a hypothetical pendulum where the mood plays the role of the suspended mass, and the force balance compensation circuitry is substituted by drug-specific therapeutic interventions. The study does not concern a model of bipolar illness that could simulate numerically various phases of mood episodes but focuses on the functional similarities regarding the correction treatments applied on the two different oscillating systems giving a potential perspective of how techniques of feedback control may enhance the conceptualization of the treatment schemes followed in recent guidelines for biological treatment of bipolar disorders. Our theoretical consideration, along with observations on clinical level, gives support to the concept that the compensation of the mood oscillations should be adaptive with selective therapeutic interventions that compensate the excited system in different time scales.

A critical evaluation of dynamical systems models of bipolar disorder

“…Mood oscillations/transitions (effect of antidepressants simulated) Deterministic dynamical system None Bonsall et al [ 28 ] DD Time-series of mood variability in stable and unstable BD (by fitting linear and nonlinear AR models to data) Fitting linear and nonlinear AR models to data QIDS-SR time-series (one measure per week over a 220-week period from 23 individuals with BD, divided into “stable mood” ( n = 11) and “unstable mood” ( n = 12) Frank [ 41 ] TD Oscillations in second messenger systems Deterministic dynamical system None Goldbeter [ 42 ] TD Mania and depression as independent, interacting systems. Mood oscillations/transitions (effect of antidepressants simulated) Deterministic and stochastic dynamical systems None Hadaeghi, et al [ 36 ] TD Mood oscillations/variations (treated vs. untreated) Deterministic dynamical system None Steinacher & Wright [ 10 ] TD Time-course of behavioral activation/approach in BD, using both deterministic and stochastic systems Deterministic and stochastic dynamical systems Qualitative description of results from Wright et al [ 50 ] Koutsoukos & Angelopolous [ 51 ] TD Energy (mood) oscillations/variations generated from a theoretical mood “pendulum” (effect of mood-stabilizers considered) Deterministic dynamical system None Bonsall et al [ 39 ] DD + TD Time-series of mood variability (by fitting linear and threshold AR models to time-series data). Mood fluctuations using both deterministic and stochastic dynamical systems (relaxation oscillators fit to time-series data) Fitting linear and threshold AR models to data Deterministic and stochastic dynamical systems QIDS-SR time-series from 61 individuals with BD (one measure per week for 79–233 weeks).…”

“…Several models attempted to capture mood oscillations [ 34 – 37 , 41 , 51 ] or circadian variations of activity in BD [ 31 – 33 , 52 ]. We will not review each study in detail, but rather discuss common features that limit the achievement of face, predictive, or construct validity.…”

A Critical Evaluation of Dynamical Systems Models of Bipolar Disorder

“…Several models attempted to capture mood oscillations [16,18,19,22,24,26] or circadian variations of activity in BD [24,31,37,38]. We will not review each study in detail, but rather discuss common features that limited achievement of candidacy for face, predictive, or construct validity.…”

For Value or for Worth? Part 2: A Neuroeconomical Thought-Action-Mood-Space Modulated by (Un-)Certainty as Sign- or Goal-tracking

“…Reward-induced invigoration along the Appropriation-axis "from Need to Pursuit" in fact causes a symmetric intensification in T~, A~ and M~. Through this analogy we start to consider coupled, usually skewed, simple harmonic oscillators (SHO as a mass-on-a-spring with (-k/m)•x = d 2 x/dt 2 obeyed by sin(x) or cos(x)) as a biaxial [133], not mono-axial [134] model of "mood swings". Hereby the above momentaneous fluctations of T~, A~, and M~ are modeled, which putatively correspond to the three "affective" CSTCs.…”