Table 1.
Description of experimental conditions (for a summary of the procedure, see Figure 1 and associated caption).
| Abbreviation | Condition name | Exchange | Food | Description |
|---|---|---|---|---|
| ETLV | Equity test, low value | Both exchange | Both low value | Both subject and partner exchanged for low value reward. |
| ETHV | Equity test, high value | Both exchange | Both high value | Both subject and partner exchanged for high value reward. |
| FC | Food control | Both exchange | Both see high value before exchange, receive low value following exchange | Prior to exchange, high value reward is held in front of exchanger and then is placed back in container. After successful completion of exchange, exchanger receives low value reward. |
| IT | Inequity test | Both exchange | Subject low value Partner high value | Partner exchanges for high value reward and subject exchanges for low value reward. |
| GR | Gift reward | No exchange | Subject low value Partner high value | Partner is given a high value reward for “free” (e.g., without exchange) and then subject is given a low value reward. |
| DT | Delay test | Both exchange, subject waits 10 s after exchange before receiving food | Both high value | Partner exchanges for a high value reward and subject exchanges and must wait 10 s before receiving high value reward. |
| DETLV | Differential exchange test, low value | Subject exchanges Partner does not exchange | Both low value | Partner is given a low value reward for “free” (e.g., without exchange) and subject must exchange for a low value reward. |
| DETHV | Differential exchange test, high value | Subject exchanges Partner does not exchange | Both high value | Partner is given a high value reward for “free” (e.g., without exchange) and subject must exchange for a high value reward. |
Not all conditions are used in all experiments, but all are provided to give an overview of the types of questions which have been asked. The most critical tests are the ETLV, which collects baseline data on responses to lower-value rewards, the IT, which collects data on responses to lower-value rewards when one's partner receives higher-value ones, and the FC, which is a control to determine reactions to lower-value rewards are present, but no primates receive one. Reprinted with permission from Brosnan et al. (2010a).