A Developmental Account of ASD
The Role of Eye Gaze in the Development of ASD
The Amygdala Theory of Autism
The Current Review
Author (Date) | Sample | ASD Severity | IQ ASD Group | Gender Breakdown | Age | Independent Variables | Dependent Variables | Visual Stimuli | fMRI task | Gaze Manipulation or Measure |
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Dalton et al. (2005) Study 1 | 14 participants diagnosed with autism or Asperger’s disorder; 12 age matched controls | All participants were verbally fluent | Full Scale IQ: M = 94, SD = 19.47 | All males | ASD: M = 15.9, SD = 4.71; Controls: M = 17.1, SD = 2.78 | ASD diagnosis; emotional expression of facial stimuli; gaze direction of facial stimuli | Whole brain activation patterns; emotion recognition accuracy & response time; time spent fixating the eyes | Black & white photographs of emotional (fearful, happy, angry) & neutral faces with averted & direct gaze from the Karolinska Directed Emotional Faces. Stimuli presented for 3 s | Facial emotion discrimination | Eye tracking used to measure eye movements & fixations |
Dalton et al. (2005) Study 2 | 16 participants diagnosed with autism or Asperger’s disorder; 16 age matched controls | 2 participants had minimal functional speech; 14 participants were verbally fluent | Full Scale IQ: M = 92.1, SD = 27.7 | All males | ASD: M = 14.5, SD = 4.60; Controls: M = 14.5, SD = 4.56 | ASD diagnosis; familiarity of facial stimuli | Whole brain activation patterns; time spent fixating the eyes | 10 photographs of the participants’ family members or friends; 10 photographs of other participants’ family members & friends | Face recognition | Eye tracking used to measure eye movements & fixations |
Dapretto et al. (2006) | 10 participants diagnosed with ASD; 10 age, gender and IQ matched controls | ADOS-G Social Subscale: M = 8.5, SD = 3.0; ADI-R Social Subscale: M = 20.3, SD 4.9 | Full Scale IQ: M = 96.4, SD = 18.3 | ASD (1 female, 9 males); Controls (1 female, 9 males) | ASD: M = 12.0, SD = 2.5; Controls: M = 12.4, SD = 2.2 | ASD diagnosis; imitation of facial emotion; observation of facial emotion | Whole brain activation patterns | 80 faces expressing 5 different emotions: anger, fear, happiness, neutrality or sadness. Stimuli presented for 2 s | Imitation and passive observation of facial expressions | Fixation cross used to cue attention to the eyes. Eye tracking used as a manipulation check |
Davies et al. (2011) | 16 children diagnosed with ASD; 16 age, gender & IQ matched controls | ADOS-G: M = 12, SD = 4.0; ADI-R: M = 21.53, SD = 7.7 | Verbal IQ: M = 100.38, SD = 19.9; Performance IQ: M = 111.13, SD = 19.83; Full Scale IQ: M = 106.19, SD = 20.31 | ASD (2 females, 14 males); Controls: (2 females, 14 males) | ASD: M = 11.69, SD = 2.71; Controls: M = 12.30, SD = 1.88 | ASD diagnosis; gaze direction of face stimuli | Whole brain activation patterns | Photographs of 160 faces with different expressions (anger, fear, happiness, neutral). 50% averted gaze & 50% direct gaze. Stimuli presented for 2 s | Passive viewing | Fixation cross used to cue attention to the eyes; eye tracking used as a manipulation check |
23 participants diagnosed with ASD; 20 age & IQ matched controls | AQ: M = 26.8, SEM = 1.4 | Full Scale IQ: M = 112.9, SEM = 3.3 | ASD (2 females, 21 males); Controls (3 females, 17 males) | ASD: M = 22.6, SEM = 1.8; Controls: M = 23.3, SEM = 1.8 | ASD diagnosis; emotional expression of facial stimuli; visual cueing to the eye region | ROI activation (left & right amygdala; superior colliculus; pulvinar nucleus of the thalamus) | 24 movies created from the NimStim database. Movies showed morphs of facial expressions from neutral to fear, happiness or anger. Movies were 5 s each | Passive viewing | Fixation cross used to cue attention to the eyes | |
Kliemann et al. (2012) | 16 participants diagnosed with ASD; 17 controls | AQ: M = 36, SD = 1.85 | Vocabulary IQ: M = 108, SD = 7.38; Strategic thinking IQ: M = 128, SD = 10.82 | All males | ASD: M = 30.44, SD = 6.34; Controls: M = 30.47, SD = 6.24 | ASD diagnosis; initial fixation; emotional expression of facial stimuli | Emotion recognition accuracy & response time; eye movements away from or towards the eye region of facial stimuli; ROI activation (amygdala) | 120 greyscale faces displaying happy, fearful & neutral expressions presented for 150 ms | Emotional classification task | Fixation cross used to cue attention to the eyes or mouth; eye tracking to measure eye movements |
Lassalle et al. (2017) | 27 participants diagnosed with ASD; 21 controls | ADOS-G: M = 6.32, SD = 1.57; ADI-R: M = 41.61, SD = 7.80 | Full Scale IQ: M = 113.15, SD = 12.36 | All males | ASD: M = 23.63, SD = 9.86; Controls: M = 19.70, SD = 7.74 | ASD diagnosis; emotional expression of facial stimuli | Whole brain activation patterns; ROI activation (amygdala, vmPFC, ACC, right STS/TPJ, & FFA) | 8 faces from the MacBrain Face Stimulus set; 4 fearful, angry, happy, & neutral expressions for each face. Stimuli presented for 300 ms | Passive viewing | Fixation cross used to cue attention to the eyes |
Perlman et al. (2011) | 12 participants diagnosed with autism; 7 age & verbal IQ matched controls | ADI-R Social: M = 21.6, SD = 3.2; ADI-R Communication Verbal: M = 16.5, SD = 4.1; ADI-R Communication Nonverbal: M = 9.0, SD = 3.0; ADI-R Stereotyped Behaviours: M = 6.1, SD = 2.4; ADOS-G Communication: M = 4.8, SD = 1.2; ADOS-G Social: M = 8.5, SD = 2.8; ADOS-G Stereotyped Behaviours: M = 1.4, SD = 1.3 | Verbal IQ: M = 106.7, SD = 11.7; Performance IQ: M = 102.2, SD = 15.8 | ASD (1 female, 11 males); Control (7 males) | ASD: M = 25.5, SD = 7.47; Controls: M = 28.57, SD = 5.74 | ASD diagnosis; visual scanpath | Whole brain activation patterns and ROI activation (amygdala & FFA). ROIs defined based on whole brain differences between NT and ASD participants during free viewing of facial stimuli | A full colour fearful, male face from the NimStim set of facial expressions, presented for 12 s | Passive viewing | Visual scanpaths defined by a moving crosshair |
Tottenham et al. (2014) | 28 participants diagnosed with ASD; 42 controls | AQ: M = 34, SD not reported | Full Scale IQ: M = 103, SD not reported | ASD (3 females, 25 males); Controls (12 females, 30 males) | ASD: M = 16, SD = 7; Controls: M = 17, SD = 8 | ASD diagnosis; visual cueing to the eye region; emotional expression of facial stimuli | Facial threat ratings; emotion recognition accuracy; eye movements towards the eye region of facial stimuli; ROI activation (amygdala) | 18 greyscale images of facial expressions (angry, neutral, happy) presented for 300 ms | Passive viewing | Visually degraded geometric shape used to cue attention to the eye region; eye tracking used as a manipulation check |
16 participants diagnosed with ASD; 18 age & IQ matched controls | ADI-R Social: M = 20.67, SD = 3.94; ADI-R; Communication: M = 12.93, SD = 4.20; ADI-R Stereotypies: M = 4.27, SD = 1.83; ADI-R Development: M = 2.93, SD = 1.44; ADOS-G Communication: M = 4.00, SD = 1.37; ADOS-G Social: M = 7.88, SD = 2.47; AQ: M = 30.46, DS = 4.6) | Performance IQ: M = 108.7, SD = 13.3 | ASD (3 females, 13 males); Controls: (2 females, 16 males) | ASD: M = 23.5, SD = 6.8; Controls: M = 25.8, SD = 5.3 | ASD diagnosis; visual cueing to the eye or mouth region; facial stimuli inverted or upright | Thatcherised stimuli discrimination accuracy; whole brain activation patterns; ROI activation (FFA; lateral occipital cortex; IFG; amygdala; pulvinar nucleus of the thalamus) | Upright or inverted pairs of facial stimuli (face with Thatcherised eyes vs. typical face; face with Thatcherised mouth vs. typical face; face with both features Thatcherised vs. typical face). Stimuli pairs presented for 1350 ms | Thatcherised face discrimination | Verbal cues to attend to changes at the eyes or the mouth | |
22 participants diagnosed with ASD; 22 controls | AQ: M = 28, SD = 7.0 | Performance IQ: M = 114, SD = 15 | ASD (3 females, 19 males); Controls (3 females, 19 males) | ASD: M = 27.6, SD = 7.7; Controls: M = 23.7, SD = 5.9 | ASD diagnosis; gaze direction of face stimuli | Whole brain activation patterns; ROI activation (thalamus, amygdala & superior colliculus) | 8 greyscale fearful faces with averted or direct gaze from the NimStim Set of Facial Expressions database. Stimuli presented for 300 ms | Passive viewing | Fixation cross used to cue attention to the eyes; eye tracking used as a manipulation check |