Amodalno kompletiranje poluzaklonjenih figura - efekat orijentacije konture

Abstract

U ovom istraživanju ispitivali smo interakciju figuralnih faktora (kontinuitet forme, C, i simetrija, S) i orijentacije (vertikalno-horizontalna i kosa) pri amodalnom kompletiranju poluzaklonjenih figura. Koristili smo tehniku primovanja. Prim i test stimulusi izloženi su u dve orijentacione pozicije, normalnoj (0o) i kosoj (45o). Primovi su bile dve iste slike (jedna pored druge): CC (petouglovi, tj. zasečeni kvadrati) i SS (šestouglovi sa dve ose simetrije) i AA (amodalni sklopovi: krug koji prekriva amodalnu figuru; kao amodalna figura može se videti ili C ili S). Redosled izlaganja stimulusa bio je: prim 400ms, ISI 20ms i test figura do odgovora. Test figure su bili parovi isto, CC i SS, i parovi različito, SC i CS. Test figure isto imale su identične primove (CC = gt CC i SS = gt SS) ili amodalne primove (AA = gt CC i AA = gt SS). Subjektima je dat zadatak da odgovore da li su figure u test stimulusu iste ili različite. Analizirana su vremena reakcije za odgovore isto. Efekat amodalnog prima bio je slabiji (duže RT) od efekta identičnog prima. Faktor rotacione pozicije nije bio značajan. Dobijena je značajna interakcija prim x rotaciona pozicija kod C test figura: efekat amodalnog prima bliži je efektu identičnog prima kada su konture orijentisane vertikalno i horizontalno. Ovakva interakcija nije dobijena kod S test figura. Zaključili smo da su simetričnije forme (kakva je S figura) otpornije na primovanje od manje simetrične C forme.

In present study the temporal dimension of amodal completion in visual occlusion was investigated. We supposed that the visual system prefers to complete normally (vertically-horizontally) oriented contours than the oblique ones. Using the prime-matching paradigm we investigated the strength of amodal primes effects on processing speed of relating test figures. Both, prime and test stimuli were presented in normal and oblique (45o) orientations. The primes were pairs of identical figures: CC (truncked squares), SS (hexagons) and AA (amodal patterns: circle occludes either amodal C or amodal S). Temporal distribution of stimuli: prime 400ms, ISIs 20ms and test figures until response. Test figures were the “same” pairs, CC and SS, and the “different” pairs, SC and CS. Each “same” test figures had its identical prime (CC = gt CC or SS = gt SS) and its amodal prime (AA = gt CC and AA = gt SS). The subjects were asked to answer whether the figures in test stimuli were same or different. The “same” RTs were analysed. The effect of amodal prime was systematically weaker (longer RT) than the effect of identical primes. Orientation was not significant factor. The significant partial interaction prime x orientation was obtained for C test figures: the effect of amodal prime was closer to effect of identical prime when the contour was normally oriented. In the case of S test figures the interaction was not obtained. We concluded that the more symmetric test figure (S) was resistant to the prime effect.