1. Categorical and coordinate spatial relations from different viewpoints in an object location memory task Ineke J. M. van der Ham, Jessie Bullens, Maartje de Goede & Albert Postma Helmholtz Institute, Experimental Psychology, Utrecht University, The Netherlands
Introduction
Categorical relations are encoded during scene perception, because changes in categorical relations (eg. left of and above) improve performance in change detection compared to coordinate changes (only varying distance) [1].
In the current study this effect is tested in an object location memory setting and from different angles. The coordinate subsystem for object recognition is viewpoint dependent, while the categorical subsytem is viewpoint independent [2]. We expect to see this difference in viewpoint dependency in object location memory as well.
Additionally, children were tested to examine the developmental processes in this task. The results can contribute to the ongoing debate on the development of categorical and coordinate relations [3,4]
Results-adults
Main effect of angle size (p<.01) and distracter type (p<.001).
Interaction of angle size and distracter type (p<.05); increase for coordinate distracters with large angle.
Fig. 3 Error rate for adults
Results-children
Main effect of angle size (p<.01), distracter type (p<.001), and age group (p<.001)
Fig. 4 Error rates for A) 5 year olds,
B) 7 year olds, and C) 10 year olds
Methods
Adults: 40 participants (20 female), age=22.1 (SD=2.1)
Children: 20 (10 female), age=5.9 (SD=0.5)
20 (10 female), age=7.9 (SD=0.4)
19 (9 female), age=10.1 (SD=0.5)
Trial design:
-memorize room with objects (15 s)
-target object on screen (2 s)
-room without 6 target objects from - same viewpoint
- small angle change
- large angle change
Stimuli: 20 rooms, each with 6 target objects, distracter locations are either both coordinately different (coo) or categorically different (cat)
Fig. 1 Trial components: room with objects, target objects, view of the room during testing phase, without the target objects and with the 3 possible locations.
Memorizing full room
target object repeated for 6 objects, with three different viewpoints
empty room with
three location options
Fig. 2 Trial sequence for each room A B C
Discussion
The adult results show a categorical advantage for all three angles. Therefore the findings on categorical coding during scene perception [1] can be extended to object location memory for scenes. Categorical performance is not influenced by angle change, while coordinate performance decreases for the large angle. This is in line with the viewpoint dependency hypothesis [2]. The categorical subsystem is viewpoint independent, while the coordinate subsystem is viewpoint dependent.
The children results show an increase in overall performance with age, while the categorical advantage is present in all age groups. The viewpoint dependency was not found here, a potential explanation is that a floor effect in performance has reduced the influence of angle on distracter type.
References
[1] Rosielle et al. (2002). Psychon Bull Rev, 9,
[2] Burgund & Marsolek (2000). Psychon Bull Rev, 7,
[3] Reese & Stiles (2005). Neuropsychologia, 43,
[4] Bullens & Postma (2008). Cognit Dev, 23, 38-47
  +31 (0) NWO Grant