165 EF and Local-global visual processing in ASD relatives

3.3.3. DFlex questionnaire: Attention to Detail

In the full sample, ASD relatives had a higher score on the Attention [V+L[HPSZJHSLVM[OL+-SL_JVTWHYLK[V;+PUKP]PK\HSZ^P[OV\[HULɈLJ[VM age or a Group x Age interaction. However, the multiplex ASD parents did not KPɈLYZPNUPÄJHU[S`MYVT;+HK\S[Z

The results of all other measures that were described in Chapters 4 and 5, but were not reported here, can be found in Appendix C (p. 180 - 183). See Table C1, Table C2 and Table C3 for the results of the main EF measures, the additional EF and control measures and the local-global WYVJLZZPUNTLHZ\YLZYLZWLJ[P]LS`(ZL_WLJ[LKUVNYV\WKPɈLYLUJLZ^LYL observed between ASD relatives and TD controls on any of these EF or local- NSVIHSWYVJLZZPUNTLHZ\YLZZPUJL[OL`HSZVKPKUV[YL]LHSNYV\WKPɈLYLUJLZ between ASD probands and TD individuals.

4. Discussion

In this chapter we investigated which cognitive characteristics are ZOHYLK IL[^LLU (:+ WYVIHUKZ HUK [OLPY ÄYZ[ KLNYLL YLSH[P]LZ ;OPZ ^HZ done by comparing the performance of these ASD relatives with that of TD individuals (matched for gender, age and IQ) on those EF and local-global WYVJLZZPUNTLHZ\YLZVU^OPJO^LWYL]PV\ZS`MV\UKKPɈLYLUJLZIL[^LLU[OL ASD probands and TD controls.

4.1. ASD relatives versus controls

4.1.1. Executive functioning

6U [OL ,- [HZRZ ^L MV\UK [OH[ (:+ YLSH[P]LZ ZOV^LK ZPNUPÄJHU[S` PTWHPYLK YLZWVUZL PUOPIP[PVU .V5V.V [HZR JVNUP[P]L ÅL_PIPSP[` >*:; >*;:HUKNLULYH[P]P[`<ZLZVM6IQLJ[Z[HZR^P[O[OLSHYNLZ[LɈLJ[ZPaL MVYNLULYH[P]P[`KLÄJP[Z;OLZLPTWHPYTLU[ZWYVIHIS`YLÅLJ[NLU\PULKLÄJP[Z in these EF domains, since groups were matched for several confounding ]HYPHISLZNLUKLYHNLHUK08UVKLÄJP[Z^LYLMV\UKVUHU`VM[OLJVU[YVS TLHZ\YLZ HUK NYV\W KPɈLYLUJLZ YLTHPULK HM[LY JVU[YVSSPUN MVY WVZZPISL JVUMV\UKPUN ,- KLÄJPLUJPLZ 0U[LYLZ[PUNS` OV^L]LY NYV\W KPɈLYLUJLZ VU JVNUP[P]LÅL_PIPSP[`HUKNLULYH[P]P[`^LYLYLZ[YPJ[LK[V[OLVWLULUKLK[HZRZ 6\YÄUKPUNZSHYNLS`JVYYLZWVUK^P[O[OLÄUKPUNZVM>VUNL[HS;OLZL H\[OVYZPU]LZ[PNH[LKJVNUP[P]LÅL_PIPSP[`NLULYH[P]P[`WSHUUPUNHUKPUOPIP[PVU TVYLZWLJPÄJHSS`PU[LYMLYLUJLJVU[YVSJVTIPULK^P[O^VYRPUNTLTVY`PU(:+ relatives compared to TD controls, and they also found the most pronounced NYV\WKPɈLYLUJLZVU[OLNLULYH[P]P[`[HZRZVUS`VWLULUKLK[HZRZ^LYL\ZLK [VTLHZ\YLNLULYH[P]P[`-\Y[OLYTVYL[OL`HSZVVIZLY]LKKLÄJP[ZPUJVNUP[P]L ÅL_PIPSP[`ZWLJPÄJHSS`PU[OL(:+WHYLU[Z>VUNL[HSZ\NNLZ[LK[OH[ [OLYH[OLYZ[Y\J[\YLKUH[\YLVM[OLPYÅL_PIPSP[`[HZRTH`OH]LTHZRLKZ\I[SL PTWHPYTLU[Z PU [OL ZPISPUNZ 6\Y ÄUKPUNZ PUKLLK PUKPJH[L [OH[ VWLULUKLK [HZRZ HYL TVYL ZLUZP[P]L [V YL]LHS NYV\W KPɈLYLUJLZ PU JVNUP[P]L ÅL_PIPSP[` but also in generativity. This might possibly explain why several other studies MHPSLK[VÄUKNYV\WKPɈLYLUJLZPU[OLZL,-KVTHPUZZLL;HISL/V^L]LY

166 EF and Local-global visual processing in ASD relatives

even when more open-ended tasks were used, ASD relatives did not always WLYMVYTKPɈLYLU[S`MYVTJVU[YVSZ)€S[L 7V\Z[RH"+LSVYTLL[HS" Gokcen, Bora, Erermis, Kesikci, & Aydin, 2009; Hughes, Plumet, & Leboyer, 1999; Schmidt et al., 2008; Sumiyoshi, Kawakubo, Suga, Sumiyoshi, & Kasai, 2011; Szatmari et al., 1993; Wong et al., 2006). This could be due to the use of a non-TD control group and/or too small sample sizes (for an overview, see ;HISL(S[OV\NO^LMV\UKZPNUPÄJHU[NYV\WKPɈLYLUJLZ[OLLɈLJ[ZPaLZ^LYL small to medium, suggesting that large samples are indeed needed to reveal them. Similar to Wong et al. (2006), we found no impairments in interference control (one type of inhibition), working memory and planning, while some other studies did (see Table 1). All of these studies included relatives with an ASD proband with low IQ (< 70; Delorme et al., 2007; Gokcen, Bora, Erermis, Kesikci, & Aydin, 2009; Hughes, Leboyer, & Bouvard, 1997; Hughes, Plumet, & Leboyer, 1999; Piven & Palmer, 1997), or did not provide information about the IQ of the proband (Koczat, Rogers, Pennington, & Ross, 2002; Mosconi et al., 2010). Other authors already referred to the possible importance of [OLWYVIHUK»Z08MVYÄUKPUNPTWHPYTLU[ZPU(:+YLSH[P]LZ4J3LHU/HYYPZVU Zimak, Joseph, & Morrow, 2014; Pilowsky, Yirmiya, Gross-Tsur, & Shalev, 2007, but see Szatmari et al., 1993). Pilowsky et al. (2007), in particular, mentioned that the “proband’s level of functioning constitutes an important JOHYHJ[LYPZ[PJYLÅLJ[PUN[OLZL]LYP[`VM[OLPYWOLUV[`WLWVZZPIS`SLHKPUN[V KPɈLYLUJLZPUNLUL[PJSPHIPSP[`HZ^LSSHZWYLZLU[PUNKPɈLYLU[Z[YLZZLZ[V[OL family” (p. 539).

On the EF questionnaires, ASD relatives showed EF impairments in daily SPML/V^L]LY[OLZWLJPÄJYLZ\S[ZMVYIV[OX\LZ[PVUUHPYLZ^LYLPUJVUZPZ[LU[ 6U [OL +-SL_ X\LZ[PVUUHPYL (:+ YLSH[P]LZ ZOV^LK JVNUP[P]L ÅL_PIPSP[` impairments, whereas on the BRIEF reduced working memory and planning abilities were found (only for the full sample), with intact inhibition and shifting abilities (generativity is not separately measured in these questionnaires). It is generally known that questionnaires have a limited construct validity. >OLUTLHZ\YPUN,-PUKHPS`SPMLP[PZOHYK[VZWLJPM`PU^OPJOZWLJPÄJKVTHPU certain impairments occur, since multiple EF abilities jointly play a role in daily life situations, making it hard to distinguish them. Nevertheless, it was surprising that even two scales that are very similar contentwise produced Z\JO KP]LYNL YLZ\S[Z 5HTLS` SHYNL NYV\W KPɈLYLUJLZ ^LYL MV\UK VU [OL JVNUP[P]L YPNPKP[` ZJHSL VM [OL +-SL_ ^P[O H TLKP\T LɈLJ[ ZPaL ^OPSL IV[O groups performed very similar on the shifting subscale of the BRIEF, with an LɈLJ[ZPaLJSVZL[VaLYV(S[OV\NO[OL+-SL_TH`ILTVYLZLUZP[P]LILJH\ZLP[ JV]LYZTVYLP[LTZTLHZ\YPUNJVNUP[P]LÅL_PIPSP[`JVTWHYLK[V[OL)90,- compared to 8 items), this could not explain the large discrepancy between both measures. Furthermore, questionnaires are the most open-ended and ecologically valid EF measures and were therefore expected to be the most ZLUZP[P]L [V YL]LHS NYV\W KPɈLYLUJLZ ;OPZ HWWLHYZ [V IL [OL JHZL MVY [OL JVNUP[P]L YPNPKP[` ZJHSL VM [OL +-SL_ ZPUJL [OL LɈLJ[ ZPaL MVY [OPZ TLHZ\YL ^HZ OPNOLY [OHU MVY HU` VM [OL ,- [HZRZ HS[OV\NO ZPTPSHY ^P[O [OL LɈLJ[ size on the Uses of Objects task). However, on the DFlex only a marginal

167