 |
The Journal of Neuroscience, May 3, 2006, 26(18):4785-4795; doi:10.1523/JNEUROSCI.4330-05.2006
Previous Article | Next Article 
Behavioral/Systems/Cognitive
Plasticity of Temporal Pattern Codes for Vocalization Stimuli in Primary Auditory Cortex
Jan W. H. Schnupp,
Thomas M. Hall,
Rory F. Kokelaar, and
Bashir Ahmed
University Laboratory of Physiology, University of Oxford, Oxford OX1 3PT, United Kingdom
Correspondence should be addressed to Jan W. H. Schnupp, University Laboratory of Physiology, University of Oxford, Parks Road, Oxford OX1 3PT, UK. Email: jan.schnupp{at}physiol.ox.ac.uk
It has been suggested that "call-selective" neurons may play an important role in the encoding of vocalizations in primary auditory cortex (A1). For example, marmoset A1 neurons often respond more vigorously to natural than to time-reversed twitter calls, although the spectral energy distribution in the natural and time-reversed signals is the same. Neurons recorded in cat A1, in contrast, showed no such selectivity for natural marmoset calls. To investigate whether call selectivity in A1 can arise purely as a result of auditory experience, we recorded responses to marmoset calls in A1 of naive ferrets, as well as in ferrets that had been trained to recognize these natural marmoset calls. We found that training did not induce call selectivity for the trained vocalizations in A1. However, although ferret A1 neurons were not call selective, they efficiently represented the vocalizations through temporal pattern codes, and trained animals recognized marmoset twitters with a high degree of accuracy. These temporal patterns needed to be analyzed at timescales of 1050 ms to ensure efficient decoding. Training led to a substantial increase in the amount of information transmitted by these temporal discharge patterns, but the fundamental nature of the temporal pattern code remained unaltered. These results emphasize the importance of temporal discharge patterns and cast doubt on the functional significance of call-selective neurons in the processing of animal communication sounds at the level of A1.
Key words: sound; training; behavior; auditory cortex; vocalization; temporal coding
Received Oct. 11, 2005;
revised March 5, 2006;
accepted March 10, 2006.
Correspondence should be addressed to Jan W. H. Schnupp, University Laboratory of Physiology, University of Oxford, Parks Road, Oxford OX1 3PT, UK. Email: jan.schnupp{at}physiol.ox.ac.uk
This article has been cited by other articles:

|
 |

|
 |
 
C. P. Billimoria, B. J. Kraus, R. Narayan, R. K. Maddox, and K. Sen
Invariance and Sensitivity to Intensity in Neural Discrimination of Natural Sounds
J. Neurosci.,
June 18, 2008;
28(25):
6304 - 6308.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. Qin, J. Y. Wang, and Y. Sato
Representations of Cat Meows and Human Vowels in the Primary Auditory Cortex of Awake Cats
J Neurophysiol,
May 1, 2008;
99(5):
2305 - 2319.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. M. M. Walker, B. Ahmed, and J. W. H. Schnupp
Linking cortical spike pattern codes to auditory perception.
J. Cogn. Neurosci.,
January 1, 2008;
20(1):
135 - 152.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. E. Russ, A. L. Ackelson, A. E. Baker, and Y. E. Cohen
Coding of Auditory-Stimulus Identity in the Auditory Non-Spatial Processing Stream
J Neurophysiol,
January 1, 2008;
99(1):
87 - 95.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. Gourevitch and J. J. Eggermont
Evaluating Information Transfer Between Auditory Cortical Neurons
J Neurophysiol,
March 1, 2007;
97(3):
2533 - 2543.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. Wang, R. Narayan, G. Grana, M. Shamir, and K. Sen
Cortical Discrimination of Complex Natural Stimuli: Can Single Neurons Match Behavior?
J. Neurosci.,
January 17, 2007;
27(3):
582 - 589.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. Gourevitch and J. J. Eggermont
Spatial Representation of Neural Responses to Natural and Altered Conspecific Vocalizations in Cat Auditory Cortex
J Neurophysiol,
January 1, 2007;
97(1):
144 - 158.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|