The Functional Role of the Anterior Insular Cortex in Cognitive Control

Cognitive control, a higher level psychological construct, refers to efficient coordination of thoughts and actions for the accomplishment of goal-directed behaviors. Cognitive control is supported by a commonly activated cognitive control network, and the anterior insular cortex (AIC) serves as one of its key structures. However, the functional role of the AIC in cognitive control has not been fully understood. A human lesion study was conducted to examine the necessary function of the AIC in cognitive control. A mouse optogenetic study with fiber photometry recording further examinedwhether the bilateral AIC was important for cognitive control and how the AIC played a role in different stages of cognitive control (e.g., state uncertainty processing, execution of control, or motor generation). Compatible versions of the post-target interference task consisting of congruent and incongruent conditions were used to measure cognitive control in humans and mice, respectively. In the human lesion study, the patients with lesions in the AIC showed longer overall response time (RT), lower overall processing efficiency, and greater conflict effects of RT and processing efficiency. These findings provided lesion-based evidence to support a causally necessary function of the AIC in cognitive control. In the mouse study, the accuracy of the congruent condition decreased when the AIC was silenced unilaterally or bilaterally by optogenetics after the cue sound and when the AIC was silenced bilaterally during the presentation of target and distractor stimuli, indicating that the disruption of the AIC resulted in a reduction in global processing efficiency. The fiber photometry results showed a significant decrease of the calcium-dependent signal after the cue sound compared to baseline, suggesting that the AIC was involved in state uncertainty processing. The results of the human lesion study identified the necessary role of the AIC in cognitive control. The findings of the mouse study further demonstrated the role of the AIC in cognitive control in both hemispheres and suggested a critical role of the AIC in state uncertainty processing

Ageing, Grey Matter Loss and Resting-State Effective Connectivity

Aldring påvirker kroppen på forskjellige måter. Ikke-patologisk aldring karakteriseres av asymmetrisk tap av grå materie, som påvirker den tjukkere hemisfæren sterkere (Roe et al., 2021). Det er ukjent hvordan disse strukturelle forandringene kan relateres til intrinsisk aktivitet som måles med «resting state» funksjonell magnetresonanstomografi (fMRI). Derfor undersøkte vi sammenhengen mellom sannsynlighetsverdier for grå materie (GMPV) og effektiv konnektivet (EC). De observerte dataene inneholder to tidspunkter, T5 og T6, fra det longitudinelle BETULA prosjektet (N = 227). Canonical Correlation Analysis indikerer relasjoner mellom EC og GMPV innom Default Mode Network og Central Executive Network. Sammenhengen mellom EC og GMPV ble spesifisert ved hjelp av generalized additive models. I tillegg fant vi forskjeller i EC mellom T5 og T6, fra venstre dorsal Prefrontal Cortex til høyre medial Temporal Gyrus og høyre Prefrontal Cortex til venstre Precuneus. Videre predikerte GMPV EC bedre enn kronologisk alder. Sammenhengen mellom strukturell og funksjonell lateralisering i de aktuelle dataene var svak. Det ble funnet markører for sammenhengen mellom hjernestruktur og -funksjon.Master's Thesis in PsychologyMAPSYK360INTL-HFINTL-MNINTL-PSYKINTL-MEDMAPS-PSYKINTL-KMDINTL-SVINTL-JU