Invention and Hypersystemising: The effects of curiosity, interest and obsession on semantic implicit learning in autistic and neurotypical individual

Autistic people require routine, engage in repetitive behaviours and have very narrow interests, termed
'obsessions' (Baron-Cohen & Wheelwright, 1999). These diagnostic-defining characteristics are
understood to be the result of hypersystemising, which is the exceptional ability many autistic people
have to detect and generate causal input-operation-output patterns of information (e.g. if the volcano
(input) erupts (operation), then it produces ash clouds (output); Baron-Cohen & Lombardo, 2017).
Hypersystemising is also posited to underlie the proclivity for talent and invention that a subset of
autistic people show in their obsession areas (Baron-Cohen & Lombardo, 2017). However, this theory
appears contradictory as it suggests the autistic preference for sameness and lawful systems is what
bolsters their creativity. So, what drives the learning of autistic people, leading to such strong semantic
specialisations?
Semantic implicit learning is the process by which individuals incidentally and without awareness
acquire information, relate it to pre-existing knowledge, derive meaning and develop a lexical form for
it. This process relies on memory, non-volitional attention and sensorimotor systems (Frensch &
Runger, 2003). Crucially, such learning often arises from the learner's intrinsic curiosity.
Curiosity is the affective state that induces the desire to learn new information, either to seek intellectual
stimulation (Interest-type) or satisfy uncertainty (Deprivation-type; Litman, 2012). It is underpinned
by the Substantia Nigra (SN) and Ventral Tegmental Area (VTA; Gruber et al., 2014), which are the
dopaminergic core of reward circuitry and, importantly, overlap with implicit learning (Batterink et al.,
2019) and systemising (Baron-Cohen & Lombardo, 2017). The few studies addressing semantic
implicit learning and curiosity, all in neurotypical adults and children, found curiosity to facilitate
memory integration (Fandakova & Gruber, 2021; Van de Cruys et al., 2021).
Curiosity may evolve into interest, which is the continuous desire to learn more about a subject. It
strongly modulates memory, predicting knowledge in both adult and infant neurotypical populations
(Ackermann et al., 2020; McGillivray et al., 2015). Only one study has addressed this phenomenon in
autistic people, revealing that interest predicts cognitive and adaptive functioning, including language,
in children aged 2-4 years (Klintwall et al., 2015). It is not, however, known how autistic people's
interests evolve from curiosity into obsessions. Although obsessions, defined as intense pondering
about a subject, are a ubiquitous autistic trait manifesting alongside highly repetitive behaviours,
nothing is known about their effects on learning as these have never been empirically studied in any
population.