A Role for the Right
A counterintuitive but essential feature of Petkov’s results, similar to the corresponding findings in the human brain, is that voice-selective activity was stronger in the right hemisphere. Furthermore, the identity-specific neuronal adaptation was observed only in the right hemisphere of the macaque brain, exactly as in the human studies. This finding means that the right hemisphere may well have played a major role in how speech appeared in our ancestors and that a response to the puzzle of speech evolution may lie not only in the left hemisphere.
We have much work ahead before we can attain a complete understanding of the functional role of the voice area, in macaques as well as in humans. Several alternative hypotheses remain to be tested: Does the voice area represent a hardwired preference for the particular acoustical structure of vocalizations from one’s own species? Or is it more simply a “formant” detector, a structure specialized in detecting vocal features in general? Another possibility is that this voice area is actually a “social” structure, tuned to vocalizations because they are cues for social interaction and not because they share a particular acoustical structure.
In conclusion, Petkov’s findings provide an exciting common substrate for high-level, or complex, auditory cognition that can be studied in parallel in humans and in macaques. Now that the location of the voice area in the macaque brain has been established, researchers will obtain critical additional information in the near future by exploring the monkey’s voice area using more conventional electrophysiological techniques, such as recording directly from neurons. Even more important, this seminal work opens the road for comparative neuroimaging studies in which humans and other animals perform similar tasks using similar methodologies, and the results can be analyzed using similar strategies.
Note: This story was originally published with the name, "Monkeys Hear Voices".
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9 Comments
Add CommentGreat resarch !!
Reply | Report Abuse | Link to thisI've been hopeing that we humanbeing could talk to other species such as monkey some day.
Amazing! Exciting! :)
Reply | Report Abuse | Link to thisWhat about dolphins? Do they not have a fairly sophisticated language?
Reply | Report Abuse | Link to thisVery interesting research. Perhaps this will do for the innate hardwired language approach what diachronic philology did for synchronic studies of language. Provided a historical and empirical foundation based on rigorous criteria of development that in a roundabout fashion led back to more thoroughly generalizable cross-sectional work.
Reply | Report Abuse | Link to thisThe interplay of discrete areas of the brain, and the synergetic structures they spawn may even lead to statistical correlations that can be empirically validated and give us a basis for quantifying the degrees of variance possible between different languages and different aspects of their development in relation to dialectal change, sound shifts, agglutination, morpheme discreteness, structural persistence of grammatical forms versus deeper syntactic relations, and even semantic developments perhaps.
Establishing a scale in the evolution of vocalization would give us a set of nodes we can study to trace a scientific line of growing communicative effectiveness until we reach the communicative leap involved in human speech and its interaction with social needs and desires and representations. A similar process in synchronic linguistics can be seen in the development of continuums and nodes to deal with the dialectal relations in communities using both creole and standard variants (of say English in Jamaica, or in south-eastern coastal parts of the US).
This would give us a cross-species web of "language" or "quasi-language" complexities open to productive cross-disciplinary investigation.
This may prove to be a small acorn planted in surprisingly fertile soil!
Pass the bananas.
Reply | Report Abuse | Link to thisRE: Cochlea defines “voice area” in our brain (monkey or human)!
Reply | Report Abuse | Link to thisDear Jonah Lehrer, Editor, Mind Matters:
Despite the nice review of the above work on the macaque brain by neuroscientist Chris Petkov, et al, at the Max Planck Institute, the questions posted by Pascal Belin were not at all critical, nor in line with the current advanced hearing or voice physiology: For example,
1] Does the voice area represent a hardwired preference for the particular acoustical structure of vocalizations from one’s own species?
[Yes, the “voice area” is anatomically and physiologically hardwired to the (evolutionally) well-defined “acoustical structure” of the “spiral cochlea” in the ear of each species (human or macaque) -- please see my seminal book “Gods, Genes, Conscience” Chapter 11.3 The Auditory and Vocal Circuitry (listed below).]
2] Or is it more simply a “formant” detector, a structure specialized in detecting vocal features in general?
[Yes, the “formant” detector is one neural circuitry that begins with the hair cells in the spiral cochlea, which electromechanically and selectively receive, transmit, and present “voice frequencies” to the “voice area” of our brain for interpretation and memory modulation -- as explained in 1] above; and also please see Chapter 15.4 Memory Modulation and Recall: A New Hypothesis of Psychic Imagery, Perceptivity, Creativity, and Reflectivity (including voices or hearing mechanism).] And last, but not least (to be continued in Part 2),
RE: Cochlea defines “voice area” in our brain (monkey or human)!
Reply | Report Abuse | Link to thisDear Jonah Lehrer, Editor, Mind Matters (Part 2):
3] Another possibility is that this voice area is actually a “social” structure, tuned to vocalizations because they are cues for social interaction and not because they share a particular acoustical structure.
[No; in my latest theory of mind or “Memophorescenicity,” the quantum mechanics of memory is that all of our auditory sensory (including visual, tactile, taste, etc) and vocal circuitries are interconnected within our brain; and closely associated (or modulated) in our memory formation and recall, including “social” identification and interaction, all those imagery recognitions that are all fundamental (or accustomed to) cues for the group survival of “social” animals, such as humans or macaques -- please see “Gods, Genes, Conscience” Chapter 15 The Universal Theory of Mind.]
Meanwhile I thought Belin, et al’s 2004 review of “Thinking the voice: Neural correlates of voice perception” is exemplary -- please see it here: http://www.psy.gla.ac.uk/docs/download.php?type=PUBLS&id=706.
Best wishes, Mong 9/13/8usct11:19a -- author-philosopher “Gods, Genes, Conscience” (iUniverse, 2006); “Decoding Scientism” and “On Consciousness” (works in progress since July 2007).
RE: Cochlea defines “voice area” in our brain (monkey or human)!
Reply | Report Abuse | Link to thisDear Jonah Lehrer, Editor, Mind Matters (Part 2):
3] Another possibility is that this voice area is actually a “social” structure, tuned to vocalizations because they are cues for social interaction and not because they share a particular acoustical structure.
[No; in my latest theory of mind or “Memophorescenicity,” the quantum mechanics of memory is that all of our auditory sensory (including visual, tactile, taste, etc) and vocal circuitries are interconnected within our brain; and closely associated (or modulated) in our memory formation and recall, including “social” identification and interaction, all those imagery recognitions that are all fundamental (or accustomed to) cues for the group survival of “social” animals, such as humans or macaques -- please see “Gods, Genes, Conscience” Chapter 15 The Universal Theory of Mind.]
Meanwhile I thought Belin, et al’s 2004 review of “Thinking the voice: Neural correlates of voice perception” is exemplary -- please see it here: http://www.psy.gla.ac.uk/docs/download.php?type=PUBLS&id=706.
Best wishes, Mong 9/13/8usct11:22a -- author-philosopher “Gods, Genes, Conscience” (iUniverse, 2006); “Decoding Scientism” and “On Consciousness” (works in progress since July 2007).
@ tictacrew We can talk to other species, I talk to my dog & cat all the time. If I spent any amount of time with a monkey, I could talk to them, people all over the world talk to other species everyday, Its just that they"re all very limited in what they have to say or think. Its only us humans that think in abstract patterns, & communicate abstract thoughts.
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