Odour Flashcards
Difficulties in Naming Odours
- Lack of smell vocabulary in western countries
- poor odour naming under experimental conditions
- difficulty in naming the source
- slow reaction times compared to other modalities
- much smell terminology reliant on subjective experience e.g. stinky, fragrant , smells like chocolate
Cain 1979 - Poor odour naming in experimental conditions
- brought ppts to lab and asked them to name familiar odours
- people were only correct around 50 % of the time
- even after receiving feedback on the correct response, people never reached the ceilings
- argued successful odour identification depends on commonly encountered substances and a long standing connection between an odour and its name and an aid in recalling the name
Aujean et al 1979 - Olfaction trade off with Vision
-proposed idea that there is a diminution of olfaction in trade-off to vision as humans have evolved
- as 3D vision has developed, eye sockets converged leading to reduction in olfactory epithelium
- it has been suggested that over time as the demands of our environment have changed, human vision has evolved with a convergence of orbits at the cost of reduced olfactory apparatus
Barton 1995 - Anatomical trade-off between olfactory and visual areas
- there is a negative correlation between olfactory and visual brain areas
Zhou et al 2011 - Human hippocampal connectivity is stronger in olfaction than in other sensory systems
- During mammalian evolution, primate neo cortex expanded, shifting hippocampal functional networks away from primary sensory cortices, towards association cortices > those in humans preferentially include higher association cortices
- olfaction unique in its rerouting, it is unsure whether it is unique to the rerouting of other somatosensory systems
combined functional neuroimaging and intracranial electrophysiology to directly compare hippocampal functional networks across human sensory systems
found that human primary olfactory cortex has stronger functional connectivity with hippocampal networks at rest compared to several other human sensory systems
Engen 1987 - Neural Connectivity
hypothesised that olfactory and language areas may be too weakly connected
- distance between hippocampus and neocortex (lang)
Lorig 1999 - Neural Connectivity
- there may be overlapping neural signals which interfere with each other causing disruption when attempting to identify odours using language
olfactory and linguistic neural representations interfere with each other > due to different temporal characteristics of auditory and olfactory systems
Scholars who have doubted the importance of smell
- Plato
- Pinker: “ smell is vestigial in humans’
- Howard Gardener: “when it comes to keen gustatory or olfactory senses, these abilities have little special value across cultures”
-Sperber (1974): ‘there is no semantic field of smells’ - Storch et al (1916): ‘neither hearing nor smell nor taste appear to be grammaticalised in other areas of linguistic structure’
Olofsson & Gottfried 2015 -Neural Connectivity
argued connections between olfactory and languages areas are too directly connected resulting in not enough time for brain to process information before it gets to language
Jahai and Basic smell vocabulary - Majid et al 2011
- traditional hunter gatherer culture in southern Asia
- have a basic vocabulary for odours - smell words are verbs and not restricted to a narrow class of objects or source descriptors
- people can easily list these odour names, demonstrating that they are psychologically salient
- knowledge of these verbs appear in everyday conversation and are not limited to specialists or mythical/religious settings
Jahai/English cross cultural/linguistic odour naming - Majid & Burenholt (2014) (METHOD)
- tested Jahai and English speakers on colour and odour naming tasks
- participants freely named colours and odours one -by one in native language
- researchers calculated agreement / consistency rather than accuracy
- used microencapsulated odours (coming from western society e.g. petrol etc)
- looked at naming consistency between cultures
Jahai/English cross cultural odour naming - Majid (2014) (FINDINGS)
- English speakers showed high agreement for colour naming but low agreement for odour naming
- English speakers used basic vocabulary for colours but source-based terms for odours
-Jahai speakers had the same level of agreement for odours and colours > in both cases they used basic vocabulary
Suggests odour naming is not universally difficult
Differences between Jahai and English Speakers which may have influenced findings (Majid, 2004)
- culture > hunter-gatherer v modern post technology
- environment > tropical rainforest v temperate climate
- biology > differences in olfactory receptor genes
Majid and Kruspe (2018) tested people from the same environment who differ in culture to tease these apart
Majid and Kruspe 2018 - Cultural comparsions: Semelai and Semaq Beri
Difference in lifestyle
- both live in Malay Peninsula > speak related languages (also both related to Jahai) > differ in subsistence style
- Like Jahai, Semaq Beri are hunter gatherers
- In contrast, Semelai are like English, non hunter-gatherers
Semelai/ Semaq Berri cross cultural odour naming - Majid (2014) (FINDINGS)
- Semelai behaved like English - displayed a high agreement for colours but low naming agreement for odours
- Semaq Berrri behaved like Jahai, no difference between odour and colour naming
Suggests that cultural differences underlie differences in odour naming