Emotional Processing and Experience in Amyotrophic Lateral Sclerosis: A Systematic and Critical Review

Abstract

Even though increasing literature describes changes in emotional processing in Amyotrophic Lateral Sclerosis (ALS), efforts to summarize relevant findings are lacking in the field. A systematic literature review was performed to provide a critical and up-to-date account of emotional abilities in ALS. References were identified by searches of PubMed, Web of Science and Scopus (1980–2021, English literature), with the following key terms: (“Amyotrophic Lateral Sclerosis” or “Primary Lateral Sclerosis” or “Motor Neuron”) and “Emotion*” and (“Processing” or “Attribution” or “Elaboration” or “Perception” or “Recognition”). Studies concerning only caregivers, pseudobulbar affect, and social cognition were excluded. Forty-one articles were included, all concerning ALS, and seven topics were identified: Emotion recognition, Emotional responsiveness, Emotional reactivity, Faces approachability rating, Valence rating, Memory for emotional materials and Alexithymia. The majority of these aspects have only been sparsely addressed. The evidence confirms altered emotional processing in ALS. The most consistent findings regard the recognition of facial expressions for negative emotions, but also alterations in the subjective responsiveness to emotional stimuli (arousal, valence and approachability), in psychophysiological and cerebral reactivity and in emotional memory, together with alexithymia traits, were reported. According to this evidence, emotional abilities should be included in the clinical assessment and therapeutic interventions.

Validity and diagnostics of the Reading the Mind in the Eyes Test (RMET) in non-demented amyotrophic lateral sclerosis (ALS) patients

“…Nevertheless, it has to be borne in mind that these results are measuredependent-i.e., are to be referred to the RMET only: while this test herewith appears to "purely" target social cognition in non-demented patients with ALS, the same might not apply to other social-cognitive measures. After all, it is indeed theoretically and empirically reasonable (Abrahams, 2011;Maresca et al, 2020;Carelli et al, 2021) to postulate that, in this population, social-cognitive abilities can be, at the same time, both linked and independent of executive/nonexecutive cognitive functions and behavioral status, as in fact suggested by the present finding of 49.9% of the variance of the RMET being unexplained by SET-EA/-IA scores.…”

“…Due to the pathophysiological and genetic link between amyotrophic lateral sclerosis (ALS) and frontotemporal degenerations, up to 50% of non-demented patients with ALS happen to show mild-to-moderate, frontotemporal-like cognitive deficits-the most prominent involving executive and language functioning-whose psychometric evaluation is clinically pivotal given their renown, detrimental impact on patients' prognosis (Strong et al, 2017). Deficits of social cognition, i.e., those sets of cognitive processes which allow to represent and process of socially relevant and emotional stimuli in order to enact adaptive behaviors within interpersonal relations (Arioli et al, 2018), are also acknowledged to feature the cognitive profile of nondemented ALS patients (Bora, 2017;Carelli et al, 2021)-with their detection being sufficient, according to Strong et al's (2017) revised consensus criteria, to classify them as cognitively impaired. More specifically, deficits in emotion processing and recognition, as well as in the ability to represent and attribute others' mental states, appear to be typical of ALS patients' cognitive phenotype (Bora, 2017;Strong et al, 2017;Carelli et al, 2021).…”

“…Deficits of social cognition, i.e., those sets of cognitive processes which allow to represent and process of socially relevant and emotional stimuli in order to enact adaptive behaviors within interpersonal relations ( Arioli et al, 2018 ), are also acknowledged to feature the cognitive profile of non-demented ALS patients ( Bora, 2017 ; Carelli et al, 2021 )–with their detection being sufficient, according to Strong et al’s (2017) revised consensus criteria, to classify them as cognitively impaired. More specifically, deficits in emotion processing and recognition, as well as in the ability to represent and attribute others’ mental states, appear to be typical of ALS patients’ cognitive phenotype ( Bora, 2017 ; Strong et al, 2017 ; Carelli et al, 2021 ).…”

“…Deficits of social cognition, i.e., those sets of cognitive processes which allow to represent and process of socially relevant and emotional stimuli in order to enact adaptive behaviors within interpersonal relations ( Arioli et al, 2018 ), are also acknowledged to feature the cognitive profile of non-demented ALS patients ( Bora, 2017 ; Carelli et al, 2021 )–with their detection being sufficient, according to Strong et al’s (2017) revised consensus criteria, to classify them as cognitively impaired. More specifically, deficits in emotion processing and recognition, as well as in the ability to represent and attribute others’ mental states, appear to be typical of ALS patients’ cognitive phenotype ( Bora, 2017 ; Strong et al, 2017 ; Carelli et al, 2021 ). Considering the ecological relevance of social-cognitive functioning, which underpins adaptive behaviors in several everyday-life scenarios ( Arioli et al, 2018 ; Maresca et al, 2020 ), as well as the overall negative impact of cognitive dysfunction on patients’ prognoses ( Huynh et al, 2020 ), the availability of statistically sound, and standardized tests to assess social cognition in ALS patients is clinically crucial.…”

Alteration of interoceptive sensitivity: expanding the spectrum of behavioural disorders in amyotrophic lateral sclerosis

“…Moreover, it has been proposed that subjective "feeling states" are dependent on the process of interoception: the representation and contextualisation of somatic and visceral responses elicited by emotional stimuli. In ALS, many components of the emotional processing are altered [23], and the insula has been suggested as a key anatomical region involved in several non-motor symptoms, including depression, anxiety, apathy, anhedonia, and fatigue [24]. However, besides interoceptive brain centres, viscerosensory afferent pathways, mainly from the vagus nerve, play an important role in modulating interoception [25,26] Accuracy in interoception is expressed as interoceptive sensitivity (IS).…”