Theory of Mind in Mild Cognitive Impairment – Relationship with Limbic Structures and Behavioural Change

Abstract

Objectives:Older adults presenting with mild cognitive impairment (MCI) have a higher risk of developing dementia and also demonstrate impairments in social cognition. This study sought to establish whether in people with MCI, poorer theory of mind (ToM) was associated with volumetric changes in the amygdala and hippocampus, as well as early changes in behaviour.Methods:One hundred and fourteen people with MCI and fifty-two older adult controls completed the Reading the Mind in the Eyes Test (RMET), while close informants (e.g., spouse/family member/friend/carer) described any current behavioural changes using the Revised Cambridge Behavioural Inventory (CBI-R). A subsample of participants completed structural magnetic resonance imaging (MRI).Results:The MCI group showed poorer performance on all neuropsychological tests administered, and moderate reductions on the RMET compared to the control group (d = .44), with greater reduction observed in those with amnestic compared to non-amnestic MCI (p = .03). While a robust correlation was identified between poorer RMET performance and smaller hippocampal volume in the control group (ρ = .53, p = .01), this relationship was not apparent in the MCI group (ρ = .21, p = .11). In the MCI group, poorer RMET performance was associated with poorer everyday skills (ρ = −.26, p = .01) assessed by the CBI-R.Conclusions:Our findings cross-validate previous reports that social cognitive deficits in ToM are a feature of MCI and also suggest that disruptions to broader neural networks are likely to be implicated. Furthermore, ToM deficits in MCI are associated with a decline in everyday skills such as writing or paying bills.

Development of a short‐form version of the Reading the Mind in the Eyes Test for assessing theory of mind in older adults

“…Our initial findings when comparing participants with intact and below average RMET performance corroborate prior work showing that poorer ToM is related to advanced age 30,31 . The relationship between ToM and global cognition also aligns with recent work demonstrating reduced RMET scores in individuals with MCI 32 . While another study showed similar RMET performance in amnestic MCI compared to healthy controls, differences in brain activation were detected in the temporal sulcus and temporal pole during task performance 9 .…”

“…It should be noted that these latter studies have focused on healthy aging, where age‐related differences are likely to be more subtle. This coupled with the abovementioned work 32 and the current analysis showing associations between ToM deficits and poorer general cognition, further highlight how general cognition and social cognition are closely linked in older adults. The presence of social cognitive deficits in older adults is very likely to indicate the presence of comorbid impairments in general cognition as well, even if they are subclinical impairments.…”

“…30,31 The relationship between ToM and global cognition also aligns with recent work demonstrating reduced RMET scores in individuals with MCI. 32 While another study showed similar RMET performance in amnestic MCI compared to healthy controls, differences in brain activation were detected in the temporal sulcus and temporal pole during task performance. 9 This association between general cognition and social cognition highlights the potential for using the short-form RMET to identify persons at risk for neurocognitive deficits or decline.…”

“…33,34 It should be noted that these latter studies have focused on healthy aging, where age-related differences are likely to be more subtle. This coupled with the abovementioned work 32 When modifying previously established psychometric scales, particularly for use in a different population than was originally designed, care should always be taken to ensure that the modified version retains as much content validity as the original version. 35 In the current scenario, modifications were made to the RMET, a scale originally developed for use in autism spectrum disorders, to retain only the items that are optimally sensitive to older adult ToM difficulties.…”

Transtornos neurocognitivos em idosos na atenção básica: o uso de instrumentos de avaliação da cognição social como método de rastreio e diagnóstico

“…No entanto, diferentemente da metanálise apresentada por Yi et al (2017) (Kynast e Schroeter, 2018). Além disso, estudos relataram que o TNL pode ser diferenciado de acordo com o acometimento em "domínio único" ou "múltiplos domínios", assim indivíduos com TNL afetando múltiplos domínios apresentariam comprometimento cognitivo social mais significativo do que sujeitos com acometimento em um único domínio (Bediou et al, 2009;Serrano et al, 2013;Michaelian et al, 2019 (Metz, 1978). Ademais, a nota de corte que apresentou maior equilíbrio entre a sensibilidade e especificidade foi oito, sendo 0,81 e 0,50, respectivamente.…”