human 137 Humans 118 male 71 female 70 adult 66 Space Perception 65 depth perception 65 article 57 Male 56 Female 54 Adult 49 physiology 46 young adult 43 Young Adult 40 Article 32 Vector spaces 32 attention 30 controlled study 29 Attention 27 human experiment 25 vision 22 Sociology 21 Astronomy, space & time 20 Space 20 Visual Perception 20 Human geography 18 Orbits 18 child 18 association 17 pattern recognition 17