Table 8. CONTINUOUS EXTENT DISRIMINTATION.
Visual and Audio-Visual Discrimination, Habituation/Familiarization Procedures
| Study | Age | Quantities Tested | Dishabituated to novel continuous extent? | Number Variables Controlled? | Dishabituated to novel numerosity? | Dishabituated to familiar continuous extent? | Difference in looking during test |
|---|---|---|---|---|---|---|---|
| Brannon, Suanda, & Libertus (2007) | 9-10 mos | 1.3 fold time duration change 3:4 | No-1 | Yes | NA | No | No |
| Brannon, Lutz, & Cordes (2006) | 5-6 mos | 1.5 fold area change 2:3 | * | Yes | NA | * | No |
| vanMarle & Wynn (2006) Visual and Auditory | 5-6 mos | 1.5 fold time duration change 2:3 | * | NA | NA | * | No |
| Brannon, Suanda, & Libertus (2007) | 9-10 mos | 1.5 fold time duration change 2:3 | Yes-1 | Yes | NA | No | Yes |
| Brannon, Lutz, & Cordes (2006) | 5-6 mos | 2 fold area change 1:2 | * | Yes | NA | * | Yes |
| Brannon, Abbott, & Lutz (2004) | 5-6 mos | 2 fold area change 1:2 | No-1 | Yes‡ | NA | No-1 | No |
| vanMarle & Wynn (2006) Visual and Auditory | 5-6 mos | 2 fold time duration change 1:2 | Yes, marginal significance reported | NA | NA | * | Yes |
| Brannon, Lutz, & Cordes (2006) | 5-6 mos | 3 fold area change 1:3 | * | Yes | NA | * | Yes |
| Cordes & Brannon (2008) | 5-6 mos | 3 fold area change 1:3 (over small number set) | No-1 | Yes‡ | No | No-1 | No |
| Cordes & Brannon (2008) | 5-6 mos | 3 fold area change 1:3 (over large number set) | Yes-1 | Yes‡ | Yes | Yes-1 | No |
| Gao, Levine, & Huttenlocher (2000) | 6-7 mos | 3 fold mass change 1:3 | Yes* | Yes | NA | No* | Yes |
| Brannon, Lutz, & Cordes (2006) | 5-6 mos | 4 fold area change 1:4 | * | Yes | NA | * | Yes |
| Cordes & Brannon (2008) | 5-6 mos | 4 fold area change 1:4 (over small number set) | Yes-1 | Yes‡ | No* | No-1 | Yes |
| Cordes & Brannon (2008) | 5-6 mos | 4 fold area change 1:4 | No* | Yes‡ | No* | No* | Yes |
| Hespos, Dora, Rips, & Christie (2012) Experiment 1 | 3-10 mos | 4 fold area change 1:4 | Yes* (7 mos old only) | Yes | * | * | Yes |
| Hespos, Dora, Rips, & Christie (2012) Experiment 2 | 7-13 mos | 3 fold area change 1:3 | No* | Yes | * | * | Yes (females only) |
| Cordes & Brannon (2011) Experiment 1a-2a | 5-6 mos | 3 fold item size change 1:3 | * | Yes‡ (Exp1a) Yes (Exp 2a) |
* | * | Yes |
| Cordes & Brannon (2011) Experiment 1b-2b | 5-6 mos | 4 fold item size change 1:4 | * | Yes‡ (Exp 1b) Yes (Exp2b) |
* | * | Yes |
This table is a list of studies that have investigated infants’ discriminations of continuous extent variables such as surface area and time duration. Column 4 indicates whether infants detected the continuous extent change that was tested. Column 5 indicates whether number was controlled. A Yes response in Column 5 indicates that researchers held the number constant across habituation and testing. A Yes‡ indicates that number was varied while the continuous extent dimension remained constant in habituation/familiarization. Column 6 indicates whether or not infants dishabituated to novel numerosities at testing. This column is only for those studies that varied number across habituation and testing in order to control number. (Thus, answering this question may only apply for studies that have a Yes‡ in Column 5.) Column 7 indicates whether or not there was a difference in looking times during testing trials alone between the novel and familiar quantity. Bolded responses throughout the table indicate those responses researchers used to concludes whether or not infants detected the quantity change.