Upload date
All time
Last hour
Today
This week
This month
This year
Type
All
Video
Channel
Playlist
Movie
Duration
Short (< 4 minutes)
Medium (4-20 minutes)
Long (> 20 minutes)
Sort by
Relevance
Rating
View count
Features
HD
Subtitles/CC
Creative Commons
3D
Live
4K
360°
VR180
HDR
14,377,206 results
I'm sure you've heard of Pavlov's Bell, but what was Ivan Pavlov up to, exactly? And how are our brains trained? And what is a ...
4,154,902 views
11 years ago
Why is it that humans react to stimuli with certain behaviors? Can behaviors change in response to consequences? Peggy ...
3,386,768 views
12 years ago
