Researchers performed experiments to explore the effects of changing-state vibrotactile sequences on short-term memory. The results revealed that short-term memory for a visual sequence is more disrupted by a changing-state vibrotactile sequence compared to a steady-state tactile sequence.
There is a duality in the central debate in contemporary cognitive psychology regarding the mechanisms underpinning interference in short-term memory. According to one standpoint, claimed by some authors, the key determinant of interference in memory is stimulus similarity/overlap, that is, interference occurs when memory representations overwrite with similar memory representations (interference-by-content).
Another alternative theoretical framework argues that interference arises instead from the conflict between similar processes being engaged concurrently, as is the case with serialization (interference-by-process). This was the perspective explored by John E. Marsh (University of Central Lancashire, UK) and his team, with the support of the BIAL Foundation.
The researchers then examined the possibility of extending a well-established auditory distraction phenomenon into the tactile domain to tease apart interference-by-content and interference-by-process accounts.
The article “Irrelevant changing-state vibrotactile stimuli disrupt verbal serial recall: implications for theories of interference in short-term memory”, published in April in the Journal of Cognitive Psychology, describes three experiments carried out to explore the effects of changing-state vibrotactile sequences on short-term memory.
In Experiment 1, it was found that the impact on visual-verbal serial recall of changing-state vibro-tactile stimuli was similar in magnitude to that for changing-state auditory stimuli. Experiment 2 demonstrated that the performance of the missing item task, requiring recall of item-identity rather than item-order, was unaffected by changing-state vibrotactile stimuli. In Experiment 3, it was established that the predictability of the changing-state sequence did not modulate the magnitude of the effect, arguing against an attention-capture conceptualisation.
The results revealed that short-term memory for a visual sequence is more disrupted by a changing-state vibrotactile sequence, i.e., dynamic distractors, which alternate from one hand to the other, compared to a steady-state tactile sequence, that is, static distractors, presented to both hands simultaneously.
These were the first experiments to explore in depth the effects of task-irrelevant vibrotactile stimuli on visual-verbal short-term memory and the functional similarity between vibrotactile and auditory distraction in this context.
According to John E. Marsh, “the results obtained by the team of researchers from the UK, Sweden, Germany, and Canada support the view that interference in short-term memory is produced by the conflict between incompatible, amodal serial-ordering processes (interference-by-process) rather than interference between similar representational codes (interference-by-content).”
Learn more about the project “The Control of Attentional Diversion: A Psychophysiological Approach” here.
