• A bit about me
• A bit about my research
• Sharing the goodness: Let's make science open

• Associate Professor of Psychology
• Founding Director of Human Imaging at Penn State's SLEIC
• Co-founder and Co-Director of the Databrary.org digital library
• A.B., Cognitive Science, Brown; M.S. & Ph.D., Psychology, Carnegie Mellon University
• Folk music, theatre, poetry, cycling, hiking, paddling, hiking/backpacking, amateur radio (K3ROG)

• What is optic flow?
• Why is optic flow important?
• How does optic flow sensitivity develop?
• How do brain systems for processing optic flow develop?
• What shapes these patterns of development?

• EEG measures of brain responses to optic flow
• Psychophysical (behavioral) measures of optic flow perception
• Empirical measures of experienced optic flow across development from head-mounted video cameras

• Structured pattern of visual motion generated by observer movement

• Geometry of environment
  • Surface layout, orientation
  • Object motion
• Direction, speed of self-motion
  • Rotation, translation
  • Visual proprioception (eye vs. head vs. body)

• Sensitivity at birth, (Jouen et al. 2000)

4-6 mo-old infants: Larger brain responses to linear patterns.

4-6 mo-old infants: Larger brain responses to faster speeds.

Sensitivity to slow (linear) speeds develops slowly in monkeys.

• Time-varying optic flow patterns.
• Steady-state visual evoked potentials (SSVEPs).
  • Event-related electro-encephalogram (EEG) technique.
  • Phase-locked responses at low-order harmonics.
• n=29 4-8 year-olds.
• (R. Gilmore, Thomas, and Fesi 2016)

• Highly responsive channels over right lateral cortex
• Radial & rotation >> translation
• Amplitude and phase differences

• Highly responsive channels over medial cortex
• Speed, but not pattern tuned, 2 < 4 = 8 deg/s
• Amplitude and phase differences

• Anatomical separation of responses
  • speed (medial)
  • vs. pattern (lateral)
• Radial & rotation != translation
• Speed tuning

• Time-varying optic flow
  • Radial, linear
  • {2 deg/s, 8 deg/s}
  • {5, 10, 15, 20%} coherence (adults)
  • {15, 30, 45, 60%} and {20, 40, 60, 80%} (children)

• n=30 children (4.3–8.6 yrs, M = 6.5 yrs, 19 Female)
  • https://nyu.databrary.org/volume/218
• n=30 adults (18.7–23.9 yrs, M = 20.8 yrs, 16 female)
  • http://doi.org/10.17910/B7V88T
  • (Adamiak et al. 2015)

• Children's behavior: more accurate to detect fast speeds, radial patterns
• Adults more accurate to detect slow speeds, radial patterns
• Response speeds in children and adults (not shown) show similar patterns
• But, why?

• External
  • Environment
• Internal
  • Posture
  • Locomotion, head, eye movements