125 Local-global visual processing in ASD

4.1.3. Processing style

The general processing style was assessed by means of the ROCF task. Here, we found that the ASD group applied a more locally oriented WYVJLZZPUN Z[`SL [OHU [OL ;+ NYV\W I\[ [OPZ NYV\W KPɈLYLUJL ^HZ VUS` WYLZLU[PUNPYSZHUKUV[PUIV`Z0U[LYLZ[PUNS`[OPZNYV\WKPɈLYLUJL^HZUV[ due to a more local processing style in girls with ASD, but resulted from a TVYL JVUÄN\YHS WYVJLZZPUN Z[`SL PU ;+ NPYSZ JVTWHYLK [V HU` V[OLY NYV\W (TD boys, ASD boys and ASD girls). In view of a general developmental shift from a more locally oriented to a more globally oriented processing style ;ZH[ZHUPZL[HSV\YÄUKPUNZZ\NNLZ[[OH[;+NPYSZHSYLHK`JVTWSL[LK this shift during childhood (8-11 years), whereas it occurs later in the other groups. So, a relatively delayed or reduced transition from a local to global processing style in girls with ASD compared to TD girls, could bring about [OLJ\YYLU[ÄUKPUNZ;VM\Y[OLY[LZ[[OPZO`WV[OLZPZHKKP[PVUHSKH[HMYVTL]LU younger girls is needed. In younger aged groups, we do not yet expect a ZOPM[LK WYVJLZZPUN Z[`SL PU ;+ NPYSZ HUK HJJVYKPUNS` UV NYV\W KPɈLYLUJLZ between ASD and TD girls. Moreover, additional data from an adult sample could specify whether this shift is simply delayed or also reduced. Pertaining [V [OL SHJR VM NYV\W KPɈLYLUJLZ PU IV`Z H Z[\K` VM ;ZH[ZHUPZ L[ HS  PUKPJH[LK [OH[ NYV\W KPɈLYLUJLZ PU THSLZ VUS` LTLYNLK K\YPUN HK\S[OVVK Similar to our study and other reports (e.g., Booth, 2006), they found no NYV\WKPɈLYLUJLZPUJOPSKYLUHNLK`LHYZWYLKVTPUHU[S`JVUZPZ[PUNVM boys) and indicate that this is due to a part-oriented (local) approach in both groups. However, in an older sample (aged 14-42 years) the TD individuals presented a more global processing style than individuals with ASD, as the ;+ NYV\W ZOPM[LK [V^HYKZ H JVUÄN\YHS HWWYVHJO ^OLYLHZ [OL (:+ NYV\W remained part-oriented (Tsatsanis et al., 2011). In sum, we only observed a more locally oriented processing style in girls with ASD, but we assume that NYV\WKPɈLYLUJLZPUTHSLZTPNO[LTLYNLK\YPUNHK\S[OVVKHNHPUZPNUPM`PUN [OLPTWVY[HUJLVMPU]LZ[PNH[PUNKPɈLYLU[NLUKLYHUKHNLNYV\WZ

4.1.4. Attention to detail in daily life

Results from the DFlex questionnaire indicated pronounced group KPɈLYLUJLZ ^P[O OLPNO[LULK H[[LU[PVU [V KL[HPS PU PUKP]PK\HSZ ^P[O (:+ compared to TD individuals. This provides a strong indication of altered SVJHSNSVIHSWYVJLZZPUNPUKHPS`SPML/V^L]LY[OLZLÄUKPUNZHYLIHZLKVUH WHYLU[YLWVY[X\LZ[PVUUHPYLHUKTPNO[[OLYLMVYLWHY[S`YLÅLJ[YLWVY[PUNIPHZLZ of the parents. Furthermore, this questionnaire confounds measures of local and global processing, as well as processing style. It is therefore unclear L_HJ[S`^OH[[OPZZJVYLYLÅLJ[Z

4.1.5. Conclusion

Although individuals with ASD display more attention to detail in daily SPML KPɈLYLUJLZ PU SVJHSNSVIHS ]PZ\HS WYVJLZZPUN HYL MHY TVYL Z\I[SL ^OLU measured with laboratory tasks. On these more controlled tasks, individuals ^P[O(:+KVUV[WYLZLU[NLULYHSNSVIHSWYVJLZZPUNKLÄJP[ZI\[VUS`ZOV^

126 Local-global visual processing in ASD

KPɉJ\S[PLZ VU [HZRZ VY [HZR JVUKP[PVUZ ^P[O OPNO PU[LNYH[P]L KLTHUKZ Furthermore, evidence is found for intact (but not enhanced) local processing abilities and a more locally oriented processing style in ASD.

The observation that reduced global processing abilities are only disclosed if integrative processes are highly taxed, corresponds to the idea of ASD as a complex information processing disorder (Bertone, Mottron, Jelenic, & Faubert, 2005; Minshew & Goldstein, 1998; Williams, Goldstein, & Minshew, 2006). According to that view, individuals with ASD show ‘selective impairments in the neural processing of complex information’, ^P[OJVTWSL_P[`ILPUNKLÄULKHZ[OLSL]LSVMKLTHUKZWSHJLKVU[OLIYHPU»Z integrative processing capacity (Williams et al., 2006). However, it is still unclear how ‘complex’ these stimuli should be and what advanced integrative KLTHUKZHYLYLX\PYLKPUVYKLY[V`PLSKNYV\WKPɈLYLUJLZ)LY[VULL[HS O`WV[OLZPaLK[OH[NYV\WKPɈLYLUJLZZOV\SKLTLYNLHZZVVUHZPU[LNYH[PVU of information cannot simply be achieved by V1, but requires activation and coordination between higher-order brain regions. Proceeding from this HZZ\TW[PVUPUKP]PK\HSZ^P[O(:+ZOV\SKZOV^KLÄJPLUJPLZVUIV[O[OL*4 task and the FOO task, since they address brain regions like MT/V5 and even the prefrontal cortex, respectively (Bar, 2003; Braddick, Atkinson, & Wattam- )LSS  6\Y ÄUKPUNZ OV^L]LY YL]LHS VUS` Z\I[SL PTWHPYTLU[Z VU IV[O tasks, depending on age and/or stimulus characteristics. We therefore argue that further research is needed to systematically investigate which factors underlie reduced global processing in ASD and are central to the altered local-global visual processing in this population.

6\Y ÄUKPUNZ WYV]PKL ZVTL Z\WWVY[ MVY [OL >** HJJV\U[ HUK [OL Enhanced Perceptual Functioning theory by demonstrating a more locally oriented visual processing style, without an overall reduction in global processing abilities in ASD. Although the initial version of the WCC account assumed reduced global processing abilities in individuals with ASD (Frith, 1989), this idea was later attenuated by proposing a less globally oriented WYVJLZZPUNZ[`SL^P[OV\[HNLULYHSNSVIHSWYVJLZZPUNKLÄJP[/HWWt -YP[O 2006). Also the Enhanced Perceptual Functioning theory postulates a more SVJHSS`VYPLU[LKWYVJLZZPUNZ[`SLPU(:+^P[OV\[LTWOHZPaPUNKPɉJ\S[PLZ^P[O global processing abilities (Mottron et al., 2006). Moreover, both theories assume increased (low-level) local processing abilities in individuals with ASD. The latter was not supported by our results. However, we measured local processing abilities with a complex conjunction VS task, in which performance is determined by multiple components. Therefore, enhanced SVJHSWYVJLZZPUNHIPSP[PLZTPNO[WVZZPIS`OH]LILLUTHZRLKI`PULɉJPLUJPLZ in other component processes, indicating that other more low-level tasks might be better suited to test local visual processing in individuals with ASD.

4.2. 0UÅ\LUJLVMZHTWSLJOHYHJ[LYPZ[PJZVUSVJHSNSVIHSWYVJLZZPUN

6UUVULVM[OLHKTPUPZ[LYLKTLHZ\YLZHTHPULɈLJ[VMNLUKLY^HZ observed. However, as mentioned above, on the ROCF task a group by gender interaction was found. Here, only the TD group showed a gender

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