The effect of mental progression on mood

Rumination as a Transdiagnostic Phenomenon in the 21st Century: The Flow Model of Rumination

Rumination and its related mental phenomena share associated impairments in cognition, such as executive functions and attentional processes across different clinical conditions (e.g., in psychotic disorders). In recent decades, however, the notion of rumination has been increasingly narrowed to the "self-focused" type in depressive disorders. A closer review of the literature shows that rumination may be construed as a broader process characterized by repetitive thoughts about certain mental contents that interfere with one's daily activities, not only limited to those related to "self". A further examination of the construct of rumination beyond the narrowly focused depressive rumination would help expand intervention opportunities for mental disorders in today's context. We first review the development of the clinical construct of rumination with regard to its historical roots and its roles in psychopathology. This builds the foundation for the introduction of the "Flow Model of Rumination (FMR)", which conceptualizes rumination as a disruption of a smooth flow of mental contents in conscious experience that depends on the coordinated interactions between intention, memory, affect, and external events. The conceptual review concludes with a discussion of the impact of rapid technological advances (such as smartphones) on rumination. Particularly in contemporary societies today, a broader consideration of rumination not only from a cognition viewpoint, but also incorporating a human-device interaction perspective, is necessitated. The implications of the FMR in contemporary mental health practice are discussed.

Using the theory of constructed emotion to inform the study of cognition-emotion interactions

In this article I suggest how theories of emotion construction may inform the study of cognition-emotion interactions. To do so, I adopt the two main concepts core affect and emotions as categories: Core affect, one's current affective state, which is defined by the two dimensions pleasure and arousal, is an inherent part of any conscious experience. Specific emotions are understood as categories including highly diverse exemplars. I argue that (1) affective states can and should not be differentiated from cognitive states, and that (2) specific emotions may follow the same principles as other biological or more general categories. I review some empirical evidence in support of these ideas and show avenues for future research.

Constricted semantic relations in acute depression

BACKGROUND

It has been suggested that mood influences the breadth of associated information available for retrieval, with positive mood broadening and negative mood constricting the scope of associations. In this study, we asked whether this mood-associations connection is related to controlled processes which were linked to clinical symptoms in depression.

METHODS

We used the semantic priming paradigm, which allows the dissociation of automatic and controlled processes by using short and long intervals between prime and target words. We further examined whether the strength of semantic relations (weak or strong) influence the priming effects in both neurotypical and depressed individuals.

RESULTS

Experiment 1, testing neurotypical individuals, showed priming effects for strong semantically-related words regardless of interval length, but priming effects for weak semantically-related words were smaller in short intervals than in long intervals. Experiment 2, testing depressed individuals in long intervals, showed smaller priming effects for weak semantically-related words than shown by neurotypicals, but priming effects for strong semantically-related words which were comparable between the groups.

LIMITATIONS

This study cannot determine the source for the differences in priming effects between depressed individuals and neurotypicals, and further studies are needed.

CONCLUSIONS

This is the first study to show priming impairments in depressed individuals. We discuss our results in light of leading theories concerning cognitive impairment in depression, as well as the newly emerged field of digital psychiatry.

How associative thinking influences scene perception

Perception of our external environment is not isolated from the influence of our internal thoughts, and past evidence points to a possible common associative mechanism underlying both the perception of scenes and our internal thought. Here, we investigated the nature of the interaction between an associative mindset and scene perception, hypothesizing a functional advantage to an associative thought pattern in the perception of scenes. Experiments 1 and 2 showed that associative thinking facilitates scene perception, which evolved over the course of the experiments. In contrast to scene perception, Experiment 3 showed that associative thinking hinders the perception of mundane objects, in which associative information is minimized. Nevertheless, object perception was facilitated when associative thinking was reduced. This double dissociation suggests that an associative mind is more receptive of externally perceived associative information, and that a match between the orientation of internal and external processing may be key for perception.

From Objects to Unified Minds

The involvement of top-down processes in perception and cognition is widely acknowledged by now. In fields of research from predictions to inhibition, and from attentional guidance to affect, a great deal has already been charted. Integrating this newer understanding with accumulated findings from the past has made it clear that human experience is determined by a combination of both bottom-up and top-down processes. It has been proposed that the ongoing balance between their relative contribution affects a person’s entire state of mind, an overarching framework that encompasses the breadth of mental activity. According to this proposal, state of mind, in which multiple facets of mind are clumped together functionally and dynamically, orients us to the optimal state for the given circumstances. These ideas are examined here by connecting a broad array of domains in which the balance between top-down and bottom-up processes is apparent. These domains range from object recognition to contextual associations, from pattern of thought to tolerance for uncertainty, and from the default-mode network to mood. From this synthesis emerge numerous hypotheses, implications, and directions for future research in cognitive psychology, psychiatry, and neuroscience.

Linking major depression and the neural substrates of associative processing

It has been proposed that mood correlates with the breadth of associative thinking. Here we set this hypothesis to the test in healthy and depressed individuals. Generating contextual associations engages a network of cortical regions including the parahippocampal cortex (PHC), retrosplenial complex, and medial prefrontal cortex. The link between mood, associative processing, and its underlying cortical infrastructure provides a promising avenue for elucidating the mechanisms underlying the cognitive impairments in major depressive disorder (MDD). The participants included 15 nonmedicated individuals with acute major depressive episodes and 15 healthy matched controls. In an fMRI experiment, participants viewed images of objects that were either strongly or weakly associated with a specific context (e.g., a beach chair vs. a water bottle) while rating the commonality of each object. Analyses were performed to examine the brain activation and structural differences between the groups. Consistent with our hypothesis, controls showed greater activation of the contextual associations network than did depressed participants. In addition, PHC structural volume was correlated with ruminative tendencies, and the volumes of the hippocampal subfields were significantly smaller in depressed participants. Surprisingly, depressed participants showed increased activity in the entorhinal cortex (ERC), as compared with controls. We integrated these findings within a mechanistic account linking mood and associative thinking and suggest directions for the future.

A Possible Role of Anhedonia as Common Substrate for Depression and Anxiety

Depression and anxiety are often comorbid, in up to 70% of cases, and the level of one or the other may fluctuate, leading now to a diagnosis of depression, now to a diagnosis of anxiety. For these reasons, and for the presence of many other common factors, it has been suggested that both are part of the same continuum of problems and that they have a common substrate. This paper proposes the possibility that anhedonia may be an important component of this possible common substrate, and it tries to identify the mechanism with which anhedonia could contribute to causing both depression and anxiety. It also proposes an explanation why an intense pleasure could improve both depression and anxiety.

Neural correlates of generation and inhibition of verbal association patterns in mood disorders

OBJECTIVES

Thought disorders such as rumination or flight of ideas are frequent in patients with mood disorders, and not systematically linked to mood state. These symptoms point to anomalies in cognitive processes mediating the generation and control of thoughts; for example, associative thinking and inhibition. However, their neural substrates are not known.

METHOD

To obtain an ecological measure of neural processes underlying the generation and suppression of spontaneous thoughts, we designed a free word association task during fMRI allowing us to explore verbal associative patterns in patients with mood disorders and matched controls. Participants were presented with emotionally negative, positive or neutral words, and asked to produce two words either related or unrelated to these stimuli.

RESULTS

Relative to controls, patients produced a reverse pattern of answer typicality for the related vs unrelated conditions. Controls activated larger semantic and executive control networks, as well as basal ganglia, precuneus and middle frontal gyrus. Unlike controls, patients activated fusiform gyrus, parahippocampal gyrus and medial prefrontal cortex for emotional stimuli.

CONCLUSIONS

Mood disorder patients are impaired in automated associative processes, but prone to produce more unique/personal associations through activation of memory and self-related areas.

When the Mind Races

Thought speed can be altered via controlled exposure to stimuli such as temporally paced text. Experiments show that thinking quickly induces positive mood and that the effect cannot be attributed to alterations of thought content or fluency. The effect is obtained across varied manipulations, including ones that alter the pace of thought involved in reading, problem solving, and visual comprehension. The experience of thinking fast signals a basic imperative for action and triggers a set of responses that mobilize the individual to act. These responses include not only heightened positive affect but also changes in behavior (i.e., increased risk taking), self-perception (i.e., increased self-confidence), and problem solving (i.e., increased creative insight). Implications of these thought-speed effects are discussed with respect to both everyday experiences that induce fast thinking and clinical psychiatric conditions (e.g., depression and mania) that are characterized by thought-speed abnormalities.

Affective value and associative processing share a cortical substrate

The brain stores information in an associative manner so that contextually related entities are connected in memory. Such associative representations mediate the brain's ability to generate predictions about which other objects and events to expect in a given context. Likewise, the brain encodes and is able to rapidly retrieve the affective value of stimuli in our environment. That both contextual associations and affect serve as building blocks of numerous mental functions often makes interpretation of brain activation ambiguous. A critical brain region where such activation has often resulted in equivocal interpretation is the medial orbitofrontal cortex (mOFC), which has been implicated separately in both affective and associative processing. To characterize its role more unequivocally, we tested whether activity in the mOFC was most directly attributable to affective processing, associative processing, or a combination of both. Subjects performed an object recognition task while undergoing fMRI scans. Objects varied independently in their affective valence and in their degree of association with other objects (associativity). Analyses revealed an overlapping sensitivity whereby the left mOFC responded both to increasingly positive affective value and to stronger associativity. These two properties individually accounted for mOFC response, even after controlling for their interrelationship. The role of the mOFC is either general enough to encompass associations that link stimuli both with reinforcing outcomes and with other stimuli or abstract enough to use both valence and associativity in conjunction to inform downstream processes related to perception and action. These results may further point to a fundamental relationship between associativity and positive affect.