The ‘affect tagging and consolidation’ (ATaC) model of depression vulnerability

Abstract

Please cite this article as: Harrington, M.O., Pennington, K., Durrant, S.J., The 'Affect Tagging and Consolidation' (ATaC) Model of Depression Vulnerability, Neurobiology of Learning and Memory (2017), doi: http://dx.doi.org/10. 1016/j.nlm.2017.02.003 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. patients, suggesting that they may be vulnerability markers of major depressive disorder (MDD), rather than mere epiphenomena of the disorder. Neuroimaging studies have revealed that depression is also associated with heightened amygdala reactivity to negative emotional stimuli, which may also be a vulnerability marker for MDD. Several models have been developed to explain the respective roles of REM sleep alterations and negatively-biased amygdala activity in the pathology of MDD, however the possible interaction between these two potential risk-factors remains uncharted. This paper reviews the roles of the amygdala and REM sleep in the encoding and consolidation of negative emotional memories, respectively. We present our 'affect tagging and consolidation' (ATaC) model, which argues that increased REM sleep density and negatively-biased amygdala activity are two separate, genetically influenced risk-factors for depression which interact to promote the development of negative memory bias -a well-known cognitive vulnerability marker for depression.Predictions of the ATaC model may motivate research aimed at improving our understanding of sleep dependent memory consolidation in depression aetiology.

The influence of REM sleep and SWS on emotional memory consolidation in participants reporting depressive symptoms

“…Another important line of research which should be pursued in the future relates to the possible relationship between biased encoding mechanisms and REM sleep in the development of emotional memory bias in depression. As discussed, the marginally greater consolidation of negative memories during late sleep in the higher BDI-II score group in this study may be related to increased amygdala activity during the encoding of negative images in this group (Bennion et al, 2015;Costafreda et al, 2013;Dannlowski et al, 2010;Harrington et al, 2017). Future research in this area will benefit from the inclusion of fMRI scanning during encoding phases to determine whether amygdala activity during encoding interacts with REM sleep in the development of negative memory bias.…”

“…According to the Affect Tagging and Consolidation (ATaC) model, heightened amygdala activity during the encoding of negative memories interacts with REM sleep alterations to promote the development of negative memory bias in individuals vulnerable to MDD (Harrington et al, 2017). It is well reported that MDD patients exhibit greater amygdala reactivity to negative emotional stimuli than healthy controls (Costafreda et al, 2013;Perlman et al, 2012;Stuhrmann et al, 2013;Suslow et al, 2010), and amygdala reactivity to negative words has been shown to correlate positively with BDI-II scores in healthy participants (BDI-II score range = 0 -10; Laeger et al, 2012).…”

“…Accordingly, increased REM density may be an endophenotype of MDD (Pillai et al, 2011). Given that REM sleep appears to play a selective role in negative emotional memory consolidation (Gilson et al, 2015;Groch et al, 2015;Nishida et al, 2009;Wiesner et al, 2015), it has been suggested that changes in REM sleep may increase vulnerability to the onset and recurrence of MDD by promoting the development of negative memory bias (Harrington, Pennington, & Durrant, 2017;Walker & van der Helm, 2009).…”

NEVER forget: negative emotional valence enhances recapitulation

“…Emotional memory biases have been observed in a range of psychopathological conditions (for a review see Haas & Canli, 2008) and have been linked with atypical encoding, consolidation, and retrieval processes. For example, patients with depression tend to remember the bad and forget the good, and there is some evidence that these negative memory biases are associated with disruptions in sleep-dependent memory consolidation processes (Goerke, Muller, & Cohrs, 2017; Harrington, Pennington, & Durrant, 2017). Patients with post-traumatic stress disorder (PTSD) show enhanced memory for trauma-related stimuli and poorer memory for emotionally neutral stimuli compared to controls (Brewin, Kleiner, Vasterling, & Field, 2007) and aberrant activation of occipital cortex during negative memory retrieval (Whalley et al, 2013).…”

Encoding, Consolidation, and Renormalization in Depression: Synaptic Homeostasis, Plasticity, and Sleep Integrate Rapid Antidepressant Effects

“…Recurrent, self-reflected, and uncontrollable rumination is one of the hallmarks of disease phenomenology (Nolen-Hoeksema et al, 2008;Hamilton et al, 2015;Whisman et al, 2020). Furthermore, depression is associated with negative biases in cognition, which predispose depressed individuals to exhibit a better recall for negative information compared with healthy subjects (Harrington et al, 2017). Patients suffering from depression may avoid social interaction and linger in despair and suicidal thoughts, often with tragic consequences.…”