The role of flicker and abrupt displacement in attention capture by motion onsets

Sunny and von Mühlenen (Psychonomic Bulletin & Review, 18, 1050–1056, 2011) showed that an onset of motion captured attention only when the motion was jerky (refreshed at 8 or 17 Hz), but not when it was smooth (33 or 100 Hz). However, it remained unclear why the onset of jerky motion captures attention. In the present study, we systematically tested the role of different aspects of jerky motion in capturing attention. Simple flicker without motion did not capture attention in the same way as jerky motion (Exp. 1). An abrupt displacement between 0.26° and 1.05° captured attention, irrespective of whether the stimulus subsequently continued to move smoothly (Exp. 2) or whether it remained stationary (Exps. 3 and 4). A displaced stimulus that was preceded briefly at the new location by a figure-8 placeholder did not capture attention (Exp. 5). These results are explained within a masking account, according to which abrupt onsets and abrupt displacements receive a processing advantage because they escape forward masking by the preceding figure-8 placeholders.     

A proposed variation of the matching technique

A matching procedure is proposed by which a judge may use the same items in different matches. TheK items in one group most likely to include the correct match with each item in the other are selected. Inclusion of the correct match among theK items chosen is defined as a success. The distribution of the number of successes is discussed. Tables are presented showing the number of successes needed for significance for various values ofK and ofN, the number of items in each group.     

Brief Daily Prayer During Holy Week

Previously a member of the Consultation on Common Texts (the organization responsible for the production of the Revised Common Lectionary). Daniel's critical edition of the Dutch Reformed Liturgy of 1767 is Bless the Lord, O My Soul (Scarecrow Press).