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Introduction: There has been a growing effort to characterize the time-varying functional connectivity of resting state (RS) fMRI brain networks (RSNs). Although voxel-wise connectivity studies have examined different sliding window lengths, nonsequential volume-wise approaches have been less common. Methods: Inspired by earlier co-activation pattern (CAP) studies, we applied hierarchical clustering (HC) to classify the image volumes of the RS-fMRI data on 28 adolescents with autism spectrum disorder (ASD) and their 27 typically developing (TD) controls. We compared the distribution of the ASD and TD groups‘ volumes in CAPs as well as their voxel-wise means. For simplification purposes, we conducted a group independent component analysis to extract 14 major RSNs. The RSNs’ average z-scores enabled us to meaningfully regroup the RSNs and estimate the percentage of voxels within each RSN for which there was a significant group difference. These results were jointly interpreted to find global group-specific patterns. Results: We found similar brain state proportions in 58 CAPs (clustering interval from 2 to 30). However, in many CAPs, the voxel-wise means differed significantly within a matrix of 14 RSNs. The rest-activated default mode-positive and default mode-negative brain state properties vary considerably in both groups over time. This division was seen clearly when the volumes were partitioned into two CAPs and then further examined along the HC dendrogram of the diversifying brain CAPs. The ASD group network activations followed a more heterogeneous distribution and some networks maintained higher baselines; throughout the brain deactivation state, the ASD participants had reduced deactivation in 12/14 networks. During default mode-negative CAPs, the ASD group showed simultaneous visual network and either dorsal attention or default mode network overactivation. Conclusion: Nonsequential volume gathering into CAPs and the comparison of voxel-wise signal changes provide a complementary perspective to connectivity and an alternative to sliding window analysis.

ti Autismikirjon piirteet ulottuvat sosiaalisten taitojen, kommunikaation, mielikuvituksen, tarkkaavuuden siirtämisen ja yksityiskohtien huomioimisen alueille. Näillä osa-alueilla esiintyviä piirteitä voidaan seuloa autismikirjon osamäärän (engl. autism spectrum quotient, AQ) avulla. Tämän tutkimuksen tavoitteena on saada suomalaiset viitearvot AQ:lle sekä tarkastella, erotteleeko AQ-lomake suomalaisia autismikirjon nuoria aikuisia oman sukupuolen nuorista aikuisista, joilla ei ole autismikirjon diagnoosia. Lisäksi tarkastellaan ryhmien suoriutumisessa olevia eroja osioittain sekä AQ:n sisäistä yhtenäisyyttä. Tutkimukseen osallistui 52 autismikirjon nuorta aikuista (39 miestä ja 13 naista) sekä 1686 verrokkia (577 miestä ja 1109 naista). Tulokset osoittavat, että autismikirjon henkilöiden pistemäärät nousevat samaa sukupuolta olevien verrokkihenkilöiden pistemääriä korkeammalle. AQ erottelee autismikirjon miehet melko hyvin verrokkimiehistä, mutta autismikirjon naiset vain kohtalaisesti verrokkinaisista. Osioanalyysissä eniten ryhmien välisiä tilastollisesti merkitseviä eroja tuli esille sosiaalisia taitoja ja kommunikaatiota mittaavissa väittämissä. Abstract Autism spectrum quotient (AQ) in screening features of autism spectrum : discriminatory ability of screening form in young adults Features of autism spectrum include areas of social skills, communication, imagination, attention switching and attention to details. These features can be screened with Autism Spectrum Quotient (AQ). The purpose of this study is to obtain Finnish performance values for AQ and to study whether the AQ discriminates Finnish young adults on the autism spectrum from same-gender controls without autism spectrum diagnosis. In addition, differences between groups in each item and internal consistency of AQ has been studied. A total of 52 young adults on the autism spectrum (39 males and 13 females) and 1686 controls (577 males and 1109 females) took part in this study. Results show that individuals on the autism spectrum have higher scores than same-gender controls. AQ discriminates quite well males on the autism spectrum from control males but only fairly females on the autism spectrum from control females. In item analysis most statistically significant differences between groups were found in items measuring social skills and communication.

Social and pragmatic difficulties in autism spectrum disorder (ASD) are widely recognized, although their underlying neural level processing is not well understood. The aim of this study was to examine the activity of the brain network components linked to social and pragmatic understanding in order to reveal whether complex socio-pragmatic events evoke differences in brain activity between the ASD and control groups. Nineteen young adults (mean age 23.6 years) with ASD and 19 controls (mean age 22.7 years) were recruited for the study. The stimulus data consisted of video clips showing complex social events that demanded processing of pragmatic communication. In the analysis, the functional magnetic resonance imaging signal responses of the selected brain network components linked to social and pragmatic information processing were compared. Although the processing of the young adults with ASD was similar to that of the control group during the majority of the social scenes, differences between the groups were found in the activity of the social brain network components when the participants were observing situations with concurrent verbal and non-verbal communication events. The results suggest that the ASD group had challenges in processing concurrent multimodal cues in complex pragmatic communication situations.