Table 1.
Predictions for the Interactive Specialization and Maturational viewpoints
| Viewpoint(s) | Feature | Prediction for developmental fMRI studies of face processing | Supported by previous studies? | Supported by present study? |
|---|---|---|---|---|
| Maturational and IS | Increased tuning of a brain region for preferred stimulus or cognitive function | 1. Specialization for faces increases with age (p. 168 for IS view); i.e., progressive changes with development. | Yes, specialization index increases with age | Yes, specialization index increases with age |
| Maturational | One-to-one correspondence between brain structure and function | 2. Only one or a few regions show increased specialization for face processing with development (p. 16) | Yes, but only tested a few regions | No, regions other than the FFA and OFA are specialized for face processing and show developmental changes |
| The brain-to-function mapping is static over development | 3. A region will either be associated with face processing or not associated with face processing across development (p. 14); hence, minimal to no activation in a region is expected prior to specialization | Not adequately tested because a specialization index of 0 cannot distinguish between lack of activation and activation that is broadly tuned (i.e., not specific for faces) | No, because no regions showed absence of activation in childhood followed by face specialized activation in adulthood | |
| IS | Brain networks or systems support a given cognitive function | 4. Multiple regions will show specialization for faces with development (p. 16) | Not adequately tested because only a few brain regions have been investigated (typically) | Yes, multiple brain regions show specialization for faces |
| The brain-function mapping is dynamic over development | 5. Regions that show specialization for face processing in adults may be partially activated in a wide variety of circumstances in children prior to specialization (p. 16) | Not adequately tested because a specialization index of 0 cannot distinguish between lack of activation and activation that is broadly tuned (i.e., not specific for faces) | Yes, because brain regions that are specialized for faces in adults show non-specific activation in childhood (i.e., associated with different cognitive functions) | |
| The same behavior is supported by different neural substrates at different ages during development | 6. Different regions or networks may show specialization for faces in children and adults (p. 167); regions specialized in children will show regressive changes and the brain will eventually develop into the adult pattern | Not tested because no prior studies have examined regressive changes | Yes, regressive changes were observed |