Correlation Lab Report – data to be run on SPSS using one tailed pearson, scattergraphs for each correlation to be included
Facial recognition; Does sensitivity to configure/featural differences in upright faces/houses predict self-reported face recognition ability?
Main Hypothesis we are testing:
- Configural sensitivity towards upright faces predicts self reported face recognition ability
- Featural sensitivity towards upright faces predicts self reported face recognition ability
- Configural sensitivity towards upright houses predicts self reported face recognition ability
- Featural sensitivity towards upright houses predicts self reported face recognition ability
The hypothesis is directional – One tailed as would expect a negative correlation as a high PI20 score corresponds with low self-reported face recognition ability. If not significant then why?
Data that needs to be analysed:
- PI20 (questionnaire measuring self reported face recognition ability) scores (high scores indicate lower self reported face recognition ability and vice versa)
- Experimental task -160 trials (data on sensitivity d)
-80 trials for each condition (ie 80 for upright faces, 80 for upright houses) of which:
-20 which differed in configuration but not features
-20 which differed in features but not configuration
-40 pairs which were identical
- If there are significant correlations then partial correlation to be run to help explore further whether effects are upright face-specific, ie does sensitivity to configural differences in upright faces explain any of the variation of self-reported face recognition ability that sensitivity to configural differences in non face objects does not
- Correlating d for configural differences in upright faces controlling for d for configural differences in upright houses
- Correlating d for featural differences in upright faces controlling for d for featural differences in upright houses
Reason behind doing the experiement:
- Previous research by Yovel & Kanwisher 2004 showed x, y, x but nor clear if a,b,c
- Failed to look at 1,2,3 hence it was decided to reperform the experiment
- Ie what hasn’t been answered by the previous resesarch
- Want to see how reliable the previous research was
Background:
- Evidence that people can recognize 5000 faces on average (but wide individual differences) – Jenkins et al., 2018
- Recognition survives well if we haven’t seen someone for a long time, or they’ve changed their appearance (hairstyle etc)
- People are also generally good at deriving other information from faces such as emotion, but again evidence of individual difference – Hoffman et al., 2010
- How good we are is surprising as we see a lot of faces and their first order configuration (nose in the middle, eyes above, mouth below) is the same.
- Individual features (nose, mouth, eye etc)
- Second order configuration (spacing)
- Holistic processing (integration of the multiple parts of a face into a single holistic representation)
- See Maurer et al., 2002 for further discussion.
- Many psychologists believe faces (particularly upright faces) and non-face objects are processed differently:
- Range of effects (composite effect, inversion effect etc) found in behavioural experiments with faces are not found (or not to the same extent) with non-face objects – Robbins & McKone, 2007
- Neuro-imaging studies show differences in activation (notably fusiform face area) – Kanwisher & Yovel, 2006
- It has been proposed:
- object processing involves decomposition into parts or features (Biederman, 1987)
- faces are represented and recognised holistically (Tanaka & Farah, 2003) and in particular relying on second-order configuration (Searcy & Bartlett, 1996)
- However, it has also been argued featural processing of faces has been underplayed:
- emphasis on configural processing often relies on assumption that inversion primarily impairs configural processing, but evidence that it also impairs feature processing (Murphy & Cook, 2017)
- Your experiment asks:
- Does sensitivity to configure differences in upright faces predict self-reported face recognition ability?
- Does sensitivity to feature differences in upright faces predict self-reported face recognition ability?
- Is this pattern the same for upright houses?
- Why is it relevant?
- Face processing is important for social interactions & deficits could contribute to isolation etc
- As well as prognosticator (face blindness) as an extreme form, various groups may have some difficulties with faces – autism (Dawson et al., 2005) and older people (Ortega & Phillips, 2007)
- Could training help? If so, configure or feature, and would it be limited to faces or include other things?
- Could configure and feature processing differences be a diagnostic tool?
- Stimuli were houses and faces which differed either in features or configuration – Yovel & Kanwisher 2004
- Stimuli were either upright or inverted, giving four conditions. This replicates Y&K but we will only give you, and you should only analyze, upright conditions
- identical
- sensitivity (d’) is a measure of accuracy which is independent of response bias
- It takes into account both cases where you correctly saw there was a difference (“hits”) and where you correctly saw there was no difference (“correct rejections”)
- Superior measure than just “hits” because it doesn’t matter in theory if you are biased towards or against reporting a difference.