TACTILE SHORT-TERM-MEMORY REVISITED

In each of three experiments subjects were required to point to the lo cation of a discrete tactile stimulus applied to the underside of the forearm after delays of 10, 15, 20, & 30 seconds. Experiment 1 showed that recall accuracy was impaired independently by both concurrent art iculatory suppression and increased delay between stimulation and reca ll. Experiment 2 compared two types of articulatory suppression task ( repeating ''the'' continuously and counting backwards in threes) and s howed that both exert the same effect on recall accuracy. Experiment 3 showed that, in comparison to a quiet condition, recall accuracy was impaired equally by: concurrent articulatory suppression; additional t actile interference; and both applied in combination. It is argued tha t articulatory suppression and tactile interference operate on separat e mechanisms to impair recall accuracy for a tactile stimulus. In part icular, tactile interference reduces the discriminability of the targe t tactile location, whereas articulatory suppression results in a depl etion of central processing resources concerned with memorisation of t he original location of the tactile stimulus. Such memorisation is not necessarily underpinned by an articulatory code.