Individual Brain Charting: HCP Relational task

This dataset contains functional magnetic resonance images (fMRIs) of 12 subjects performing HCP Relational task that employed a relational match-to-sample paradigm, featuring a second-order comparison of relations between two pairs of objects. It served primarily as a localizer of the rostrolateral prefrontal cortex, since relational matching mechanisms have been shown to yield activity in this region. Similar to some previous tasks, the paradigm included two categories of blocks, namely relational-processing and control-matching blocks. All blocks were constituted by a set of events. In the relational-processing block, visual stimuli consisted of images representing two pairs of objects, in which one pair was placed at the top and the other one at the bottom of the image, respectively. Objects within a pair may differ in two features: shape and texture. The participants had to identify whether the pair of objects from the top differed in a specific feature and, subsequently, they were asked to determine whether the pair from the bottom changed along the same feature. For the control block, one pair of objects was displayed at the top of the image and a single object at the bottom of the same image. In addition, a cue was shown in the middle of that image, indicating which feature is relevant. The participants had thus to indicate whether the object from the bottom was matching either of the two objects from the top, according to the feature specified as a cue. This task included twelve blocks per run, with six blocks per category. Block categories were, in turn, interleaved for display within a run. A fixation-cross period of sixteen seconds was inserted between some blocks. All blocks contained six trials and they were always initiated by a cue of two seconds. The trials were described by a visual-stimulus plus response period followed by a fixation-cross period, lasting up to ten seconds. The duration of the former was nine seconds and 7.6 seconds during the relational-processing block and controlmatching block, respectively. [https://openfmri.org/dataset/ds000244/](https://openfmri.org/dataset/ds000244/) [https://neurovault.org/collections/2138/](https://neurovault.org/collections/2138/)