They are mini blocks which include more detail.
The 180 trials were split into 12 trials of each ratio/set-size combination, which were then further split into three 4-trial mini blocks (randomly selected), giving a total of 45 mini blocks.
These trials were presented 1) once or twice in isolation, 2) once in a sequence of 2, and 3) once in a sequence of 3 consecutive trials of the same condition ("mini blocks") to enhance BOLD signal strength during event-related designs (Amaro and Barker 2006; Kircher et al. 2009; Sass et al. 2009a, 2009b).
Each stimulus class was presented in 4-s mini-blocks with items presented at 2 Hz (eight items per mini-block).
In each run, 12 mini-blocks of each class were presented along 12 interspersed 4-s fixation blocks (acquisition time: 5 min 13 s).
Silva, who has permission to live and work in the US under Obama's deportation relief program for young people, appeared during a mini-block of immigration-themed speeches, following 11-year-old Karla Ortiz and her mother, Francisca.
Z-scores were calculated using mean and standard deviations of each mini-block of 32 trials.
The data were analyzed for main effects of ratio (5 levels: 9 mini-blocks each) and set-size (3 levels: 15 mini-block each).
In the present study, each "block" is in fact a mini-block with duration of several hundred milliseconds (i.e. the reaction time in the individual trial), with steep increase of the slope at stimulus onset, remaining on the activity plateau for the short period until button press (reaction time), and final return to baseline.
The manufacturer defines a mini-block as a group of four probes that include a PM and a MM probe for allele 1, and a PM and a MM probe for allele 2. The Mapping 10 K Array contains ten mini-blocks, 5 of which correspond to the forward strand and the other five to the reverse strand.
