A vehicular interior rearview mirror assembly includes a mirror head adjustable about a mounting structure configured to mount the mirror assembly at an interior portion of a cabin of a vehicle. The mirror head accommodates an electronic component. When the electronic component is electrically operated, the electronic component generates heat within an interior cavity of the mirror head. An aerogel-infused material is disposed within the interior cavity of the mirror head and thermally conductively connects the electronic component with at least a portion of the mirror casing. The aerogel-infused material, when the electronic component is electrically operated and generates heat within the interior cavity of the mirror head, reduces thermal transfer between the electronic component and at least the portion of the mirror casing.