Khan Academy

Originally simply a collection of videos on YouTube, Khan Academy has developed into a fully-featured website that also offers exercises to complement its video library, a discussion forum, and a "knowledge map," which illustrates the connection between content areas. The advantages of Khan Academy are obvious: in true democratic fashion, anyone with access to the Internet can now have good-quality, free instruction in the various disciplines of mathematics and the sciences. And yet Khan Academy's videos teach only the techniques necessary to solve problems like those featured in the videos; the viewer, just as the student in the "traditional" classroom, is not often invited to consider why things are as they are, but must accept on authority that they are so. Further, there can never be conversation between video and viewer as there is ideally between student, teacher, and peers in the classroom.

For those interested in other perspectives on Khan Academy, Zack and I have prepared a list of supplemental readings, which can be found on our Bitly page.

+Binaural Beats

     This week Philip G. and I made our presentation on binaural beats.  The presentation can be found at the end of this post.  Essentially, binaural beats are two channels of slightly different frequencies, each played in one ear of a set of headphones.  Our brains perceive a pulsing of sound due to the perceived alternating of constructive and destructive interference.  One thing which I forgot to mention during the presentation is that the speed of the pulsing is equal to the difference of the two tones being listened to.  So if one ear hears 100 Hz and the other hears 105 Hz, the pulsing is at a rate of 5 Hz, or 5 pulses per second.  The hope of binaural beats is that this pulsing or beating will cause the brains waves to be drawn toward that frequency.  While I would like to see more studies on how exactly electrical signals in the brains are affected, I think there is enough evidence to be cautiously optimistic that there are positive effects.  At the very least, I think it is helpful to sometimes have a steady sound to help keep focused, so long as it is not played too loudly.  In The Shallows, Nicholas Carr lists four categories that all technologies can be placed into: those that extend our physical strengths  those that extend our range or sensitivity of our sense, those that enable us to reshape nature, and those that "extend or support our mental powers - to find and classify information, to formulate and articulate ideas, to share know-how and knowledge, to take measurements and perform calculations, to expand the capacity of our memory" (44).  Binaural beats, whether placebo effect or true science, is a technology that can extend and support our mental powers.



 

YouTube:
Last week, we presented on YouTube and the EDU portion of YouTube.
For more information, see our Presentation