Article: Tang, C., S. Hamilton, and E.F. Chang. “Intonational Speech Prosody Encoding in the Human Auditory Cortex.” Science 357, no. 6353 (2017): 797–801. DOI: 10.1126/science.aam8577
Assignment: Read the assigned article carefully (expect this to take at least two hours, possibly more) and think about it, then provide short answers to the questions below. You can do this by responding straight on this document or by submitting a separate document with numbered answers. Be clear and concise, points will be taken off for unnecessary words.
A few things that are not well explained in the paper:
- I didn’t see a definition of H gamma (indicated as the Greek letter which I cannot get my text editor to make) in the figures – this is just “high gamma power”, which is the main measure of neural response used in this paper and in other intracranial recording studies.
- When the paper refers to “spectral information” (which I highlighted in orange), that just refers to different amounts of power at different frequencies. See the “spectrogram” in Figure 1A, which shows auditory power (darkness) as a function of time (x axis) and auditory frequency (y axis).
- You can ignore the stuff about the “missing fundamental” (highlighted in orange).
TA tip: when reading, try to focus on the figures and make sure you understand them. Refer back to the text for supporting information when needed.
- What method does this paper use?
- What is the main (most important) empirical finding in the paper? What figure illustrates this finding?
- What is the design of this experiment? That is, what factors were manipulated (list each), and how many different conditions were used?
- What does Figure 1E show?
- The middle graph in figure 2N shows 147 electrodes that had information about which sentence was spoken. Could you decode from these electrodes whether the speaker saying those sentences was male or female?
- Would you expect the electrodes that can discriminate intonation to be able to discriminate musical melodies (in which each note has a different pitch)? If so, how would you characterize the function of those sites?
- If the same experiment were repeated using fMRI, what results would you expect?