Limits...
Haptic subitizing across the fingers.

Plaisier MA, Smeets JB - Atten Percept Psychophys (2011)

Bottom Line: Our results showed that subitizing was not possible for raised lines among flat surfaces, whereas this type of stimulus could be detected in parallel over the fingers.In the latter case, the lack of tactile input is essential, since subitizing was not enabled by differences in proprioceptive information from the fingers.Our results show that subitizing using haptic information from the fingers is possible only when some fingers receive tactile information while other fingers do not.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Human Movement Sciences, VU University, Van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands. M.Plaisier@fbw.vu.nl

ABSTRACT
Numerosity judgments of small sets of items (≤ 3) are generally fast and error free, while response times and error rates increase rapidly for larger numbers of items. We investigated an efficient process used for judging small numbers of items (known as subitizing) in active touch. We hypothesized that this efficient process for numerosity judgment might be related to stimulus properties that allow for efficient (parallel) search. Our results showed that subitizing was not possible for raised lines among flat surfaces, whereas this type of stimulus could be detected in parallel over the fingers. However, subitizing was possible when the number of fingers touching a surface had to be judged while the other fingers were lowered in mid-air. In the latter case, the lack of tactile input is essential, since subitizing was not enabled by differences in proprioceptive information from the fingers. Our results show that subitizing using haptic information from the fingers is possible only when some fingers receive tactile information while other fingers do not.

Show MeSH
Setup and results of Experiment 3. The meaning of the symbols is the same as in Figs. 2 and 3. a Items consisted of high and low wooden blocks. b Response times and error rates as a function of the number of items. c Slopes from the single-subject response times averaged over subjects for small and medium numerosities
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3118010&req=5

Fig3: Setup and results of Experiment 3. The meaning of the symbols is the same as in Figs. 2 and 3. a Items consisted of high and low wooden blocks. b Response times and error rates as a function of the number of items. c Slopes from the single-subject response times averaged over subjects for small and medium numerosities

Mentions: The same subjects as in Experiment 1 and 2 participated. The methodwas again as described in Experiment 1, except that items consisted of high (4 cm) and low (2 cm) wooden blocks. The hands rested on a 4.5-cm raised surface such that the fingers were slightly elevated above the blocks (Fig. 3a), and subjects moved their fingers down until all fingers were touching a block. Subjects were instructed to respond with the number of high blocks.Fig. 3


Haptic subitizing across the fingers.

Plaisier MA, Smeets JB - Atten Percept Psychophys (2011)

Setup and results of Experiment 3. The meaning of the symbols is the same as in Figs. 2 and 3. a Items consisted of high and low wooden blocks. b Response times and error rates as a function of the number of items. c Slopes from the single-subject response times averaged over subjects for small and medium numerosities
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3118010&req=5

Fig3: Setup and results of Experiment 3. The meaning of the symbols is the same as in Figs. 2 and 3. a Items consisted of high and low wooden blocks. b Response times and error rates as a function of the number of items. c Slopes from the single-subject response times averaged over subjects for small and medium numerosities
Mentions: The same subjects as in Experiment 1 and 2 participated. The methodwas again as described in Experiment 1, except that items consisted of high (4 cm) and low (2 cm) wooden blocks. The hands rested on a 4.5-cm raised surface such that the fingers were slightly elevated above the blocks (Fig. 3a), and subjects moved their fingers down until all fingers were touching a block. Subjects were instructed to respond with the number of high blocks.Fig. 3

Bottom Line: Our results showed that subitizing was not possible for raised lines among flat surfaces, whereas this type of stimulus could be detected in parallel over the fingers.In the latter case, the lack of tactile input is essential, since subitizing was not enabled by differences in proprioceptive information from the fingers.Our results show that subitizing using haptic information from the fingers is possible only when some fingers receive tactile information while other fingers do not.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Human Movement Sciences, VU University, Van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands. M.Plaisier@fbw.vu.nl

ABSTRACT
Numerosity judgments of small sets of items (≤ 3) are generally fast and error free, while response times and error rates increase rapidly for larger numbers of items. We investigated an efficient process used for judging small numbers of items (known as subitizing) in active touch. We hypothesized that this efficient process for numerosity judgment might be related to stimulus properties that allow for efficient (parallel) search. Our results showed that subitizing was not possible for raised lines among flat surfaces, whereas this type of stimulus could be detected in parallel over the fingers. However, subitizing was possible when the number of fingers touching a surface had to be judged while the other fingers were lowered in mid-air. In the latter case, the lack of tactile input is essential, since subitizing was not enabled by differences in proprioceptive information from the fingers. Our results show that subitizing using haptic information from the fingers is possible only when some fingers receive tactile information while other fingers do not.

Show MeSH