6a. the social and emotional brain

explain the social brain hypothesis

intelligent behaviour is primarily formed by aspects of our social life, and to keep up with complex social demands

define feeding ecology

how a species obtains and uses food in its natural environment

explain the ecological intelligence hypothesis

differences in feeding ecology create differing cognitive demands

variance in feeding ecology can predict differences in neurological traits like neocortex size

how can we investigate the speed of processing social norms

using EEG/MEGs

the human brain extracts info about people’s actions but the process is relatively slow

suggesting it is likely a complex process needing many different brain areas

name the areas of the brain involved in facial recognition and eye gaze detection

facial recognition = fusiform facial area (FFA)

eye gaze detection = superior temporal sulcus (STS)

explain the model of haxby et al 2000

suggests we have a core and extended system of brain areas that work together to detect faces, eyes and emotions

detail the role of the superior temporal sulcus in eye movement detection

inhibition of the right superior temporal sulcus led to participants looking less at the eye area

shows the sts plays a role in directing attention to the eyes

detail the role the superior temporal sulcus plays in eye gaze detection

mutual gaze evoked more activity in the sts than averted gaze

suggests the sts is involved in the visual analysis of social information (that we get from eye gazes)

explain the role of the superior temporal sulcus in violations of expectation

sts is sensitive to violations of expected gaze shift - registering this violation between actual and predicted behaviour

explain the role of the superior temporal sulcus in direction of attention

sts is just as active when someone points in a direction as when someone looks in a direction - suggesting it is activated by any directional cues

explain the role of the superior temporal sulcus and biological motion

the sts responds more strongly to moving bodies than random motion - assessed using the light dots on bodies experiment (point-light experiment)

how does superior temporal sulcus activation relate to motion and social interaction

sts is active during the processing of social interaction - showing it reflects perception of social interaction not just motion alone

explain the third visual pathway

neural network that is specialised to the processing of complex social information, like body movements and eye gaze

how does the superior temporal sulcus work together with other areas to process social information

works with visual areas:

• fusiform gyrus - facial identity

and non visual areas:

• parietal regions - attention

what have fMRI scans shown about foetuses and their preferences for faces

foetuses prefer upright compared to inverted face-like patterns

they also have a preference for faces with more elements in the upper half of the face to the lower half

state the results of a study on infants and eye gaze detection

newborns prefer to look at faces that engage in mutual gaze (eye contact)

explain newborns and biological motion

at 2 days old infants are able to tell the difference between scrambled motion and biological motion

but they do not show a preference

is the specialisation of the superior temporal sulcus in complex social signals innate

no - it develops gradually through development