Information Technology Reference
In-Depth Information
Fig. 2.
Three types of heuristics in 4*4 Sudoku
-
The last heuristics involves checking three dimensions: (Row and Column
and Box), as shown in part (c) of Figure 2. Three digits in the set of 1 to 4
are given in the row, column and box with grid of '?', only one digit in each
dimension.
The first three heuristics checking only one dimension are called as simple heuris-
tics, and the resting four heuristics checking one or two more dimensions as
complex heuristics.
Materials and Procedure
. The tasks in this experiment are to solve the prob-
lem using only one of above heuristics. Therefore, the experiment materials are
two types of 4*4 Sudoku problems. The visual stimuli of the tasks also are those
as shown in Figure 2. The experiment took two steps. Firstly, before fMRI scan-
ning, all participants are trained to get familiar with the seven heuristics and
to be able to use these heuristics to solve the corresponding problems. Secondly,
the participants performed tasks in MRI scanner with more than 80 trials.
Experiment Procedure
. A trial begin with an alerting stimulus presents for
two seconds followed by a 4*4 Sudoku stimulus that stays on the screen until
the participant indicates they know the answer or 20 seconds has elapsed. When
participants feel that they has found the answer of the problem, they press a
key under the thumb of their right hands and then speak out the answer. Then
the Sudoku stimulus is cleared. The ACT-R model simulates the processes from
the presentation of stimulus to the key pressing.
fMRI Scan
. Event-related fMRI data were collected by a gradient echo planar
pulse acquisition on a Siemens 3T Trio Tim Scanner. Behavioral data and fMRI
brain imaging data of 16 participants were collected.
Data Analysis and Results
. Behavioral results RT (mean of response time
over 16 participants) of the two types of 4*4 Sudoku, were calculated. Functional
fMRI results, BOLD (Blood Oxygenation Level-Dependent) responses in five
predefined brain regions based on [6] were also calculated.
