Portable terminal and method for controlling same

To reduce the number of erroneous detections and power consumption and increase the speed of a response to an operation, a portable terminal (10) includes (i) a determining unit (22) configured to determine whether a sensing signal output from at least one of a first electrode (1A) and a second electrode (1B) has an absolute value of not less than a first threshold or not greater than a second threshold and (ii) a determination period control unit (23) configured to perform a process of shortening a determination cycle in a case where the determining unit has initially determined that the absolute value of the output is not less than the first threshold or in a case where the determining unit has initially determined that the absolute value of the output is not greater than the second threshold.