Pauline Insch, Louise Phillips, Roy Allen & Rebecca Bull
Aging, Cognition and Emotion Laboratory, School of Psychology, University of Aberdeen.
The ability to decode body movement, as cues to emotions and Age was negatively correlated with the perception of biological motion
actions, is argued to be a fundamental precursor to inferring the for both actions and emotions. Accuracy on both the biological motion
mental states of others. Biological motion has been used to tasks correlated with accuracy at identifying the global incongruent trials
investigate the capability to decode these movements However, to in the global-local recognition task (See table 1 below).
decode biological motion the figures must be processed holistically Table 1: Correlations between age, biological motion & global-local processing conditions.
by the visual system. In these point-light figures the local aspects
(point-lights) differ from the global form (a person). Failure to Variable 1 2 3 4 5 6 7
holistically group the local aspects means perception of the figure ** ** * **
will not be achieved. Typically the visual system preferentially 1. Age - -.471 -.372 -.181 -.111 -.162 -.415
2. BM Action - .441 .134 .046 .038 .266
processes stimuli holistically, although there is some evidence of 3. BM Emotion - .013 -.004 - .012 .245
age-related. Local bias has been found in older adults and also in 4. Local Congruent - .262
conditions with social difficulties such as Autistic Spectrum 5. Local Incongruent - -.031 .336
Disorder and Alzheimer’s disease. 6. Global Congruent - .112
7. Global Incongruent -
STUDY AIMS *P< .05 (2-tailed) **P < .01 (2-tailed) (%age accuracy figures used for BM & G/L processing)
• The principle aim was to investigate if biological motion perception
was subject to age effects when stimuli showing actions and Task 1: Biological Motion Perception
emotions were presented; • Significant age effects were found in the ability to perceive biological
• A secondary aim was to investigate if there were age effects motion (F(2,119) = 18.13, p < .01);
apparent in the ability to process global incongruent stimuli; • There were no significant group differences between young and older
• Finally this study analysed how biological motion perception may adults for either action or emotion recognition;
be moderated by both age and global-local biases. • The older adults in contrast showed significant decline in perceiving
both actions and emotions when compared to both young and middle-
METHOD aged groups suggesting difficulties start in old age;
Participants (n = 121) • Stimuli type was significant with emotions being harder to decode than
52 young, aged 18 – 39 (M = 25.81, SD = 5.45), 38 middle-aged, actions for all age categories (F(1,119) = 16.25, p < .01).
40 – 64 (M = 51.53, SD = 8.73 and 32 older adults, 65 - 88 • There was no age x stimuli interaction (F (2,119) = 2.12, p = ns).
(M = 73.16, SD = 4.72) took part in both tasks.
Task 2: Global-Local Processing Biases
Task 1: Biological Motion • A significant effect of age was found with the older adults showing the
Twenty four short biological motion films were shown. Twelve of poorest performance (F (2,119) = 18.13, p <.01);
the films depicted actions such as driving, while twelve showed the • The type of task was also significant as the global-incongruent
emotions anger, fear, sadness and happiness. Each of these condition was most difficult (F(1.57,115) = 31.41, p < .01);
emotions were shown at three different levels of intensity • There was a significant task x age interaction (F (3.14,115) = 8.75
(See figure 1 for examples). p <.01), with the largest age effect on measures of global bias.
Action Stimuli Emotion Stimuli Global Incongruent Accuracy
Percentage Accurate Responses
Action Stimuli: Driving Emotion Stimuli: Anger
Intensity = low Young Middle-Aged Older
Figure 1: Example of Action and Emotion Point-Light Stimuli Participant Age Categories
Task 2: Global-Local Processing Figure 3: Age effects on biological motion and global-incongruent processing accuracy.
Images of shapes were presented. These consisted of a global
shape comprised of local shapes. Both types of shape could be • An analysis of co-variance showed that even when shared variance
either circles, diamonds, squares or triangles. When the shapes between biological motion perception and global-incongruent
were blue participants had to identify the global shape. When the processing was removed, the main effect of age was maintained but
shapes were red participants were required to identify the local reduced to F (2,116) = 13.45, p = <.01.
shape. There were four conditions (see Figure 2), determined by
colour and global/local shape congruency DISCUSSION
Age differences in identifying biological motions from actions and
Congruent Congruent Incongruent emotions were found. This replicates previous findings of decline in
emotion recognition over the lifespan. This study was the first to
highlight how biological motion perception may be moderated by both
age and visual processing style. Research has previously suggested that
difficulty in global processing impacts on social cognition and this may
reflect neuropsychological changes within those middle-aged and older
Global response = Circle Local response = Circle, = Square
adults which causes changes in the bias towards global processing.
Figure 2: The Global/Local, Congruent/Incongruent conditions
The Leverhulme Trust