Our brain processes auditory inputs in highly complex and sophisticated ways, and there are many interesting findings, tricks and (some outrageous) claims.
Scientists have found strong effects on brain activity from certain types of sounds, you can follow this link (http://www.ncl.ac.uk/press.office/press.release/item/nasty-noises-why-do...) and do your own research on this topic on the effects of disgusting sounds and comforting sounds.
For the binaural beats effect, you can search the web by typing "binaural beats" or read the introduction at wikipedia (http://en.wikipedia.org/wiki/Binaural_beats) and go from there.
Armed with DIY biosensor kit, you now have the opportunity to observe and evaluate these various effects on yourself, rather than just hearsay.
What you need:
1. Setup DIY biosensor kit: EEG sensor (or ECG, SCR for more correlations), tagging widget (either a hardware tagger, or a software tagger).
2. Find source material: you can find many on the web, or create your own source material, or use some examples provided here.
3. Start recording your sensor data, play (and tag) the selected material, tag the beginning, the end and any special moments in between.
4. Playback the material and your bio-responses, share them here if you want to.
Links:
http://www.ncl.ac.uk/press.office/press.release/item/nasty-noises-why-do...
http://en.wikipedia.org/wiki/Binaural_beats
References:
Kumar et al (2012). Features vs. Feelings: Dissociable representations of the acoustic features and valence of aversive sounds. Journal of Neuroscience
http://www.jneurosci.org/content/32/41/14184
Source Materials:
Binaural beats:
1. Binaural (528Hz) beat 8Hz: 10" (no beat) + 20" (R>L) + 20" (L>R) + 10" (no beat).
2. Binaural (528Hz) beat 4Hz: 10" (no beat) + 20" (R>L) + 20" (L>R) + 10" (no beat).
Nasty noises:
1. Knife on a bottle
2. Fork on a glass
3. Chalk on a blackboard
4. Ruler on a bottle
5. Nails on a blackboard
6. Female scream
7. Anglegrinder
8. Brakes on a cycle squealing
9. Baby crying
10. Electric drill
Least unpleasant sounds:
1. Applause
2. Baby laughing
3. Thunder
4. Water flowing
Other sounds:
1. Heart beat: your own, your close friend, your mom
2. Brain activity (transposed): while you work, meditate, sleep