The influence of short-term memory on standard discrimination and cued identification olfactory tasks.
BACKGROUND
Amongst the techniques to assess olfactory functions, discrimination and cued identification are those most prone to the influence of odour short-term memory (STM). Discrimination task requires participants to detect the odd one out of three presented odourants. As re-smelling is not permitted, an un-intended STM load may generate, even though the task purports to assess discrimination ability. Analogously, cued identification task requires participants to smell an odour, and then select a label from three or four alternatives. As the interval between smelling and reading each label increases this too imposes a STM load, even though the task aims to measure identification ability.


METHODS
We tested whether modifying task design to reduce STM load improve performance on these tests. We examined five age-groups of participants (Adolescents, Young adults, Middle-aged, Elderly, very Elderly), some of whom should be more prone to the effects of STM load than others, on standard and modified tests of discrimination and identification.


RESULTS
We found that using a technique to reduce STM load improved performance, especially for the very Elderly and Adolescent groups.


METHODS
Sources of error are now prevented.


CONCLUSIONS
Findings indicate that STM load can adversely affect performance in groups vulnerable from memory impairment (i.e., very Elderly) and in those who may still be acquiring memory-based representations of familiar odours (i.e., Adolescents). It may be that adults in general would be even more sensitive to the effects of olfactory STM load reduction, if the odour-related task was more difficult.
Department of General Psychology, University of Padova, Italy. Electronic address: zucco@unipd.it.
Gesualdo M
GM
Zucco
Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden, Germany.
Thomas
T
Hummel
Department of General Psychology, University of Padova, Italy.
Francesco
F
Tomaiuolo
Department of Psychology, Macquarie University, Sydney, Australia.
Richard J
RJ
Stevenson
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003463:Cues; D004192:Discrimination, Psychological; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D009483:Neuropsychological Tests; D009812:Odorants; D055696:Olfactory Perception; D010812:Physical Stimulation; D021641:Recognition, Psychology; D013647:Task Performance and Analysis; D055815:Young Adult
Age-related changes; Olfactory assessment; Short-term odour recognition memory; Standard vs modified odour discrimination; Standard vs modified odour identification