Olfactory cortical adaptation facilitates detection of odors against background

被引:84
作者
Kadohisa, M [1 ]
Wilson, DA [1 ]
机构
[1] Univ Oklahoma, Dept Zool, Norman, OK 73019 USA
关键词
D O I
10.1152/jn.00812.2005
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
Detection and discrimination of odors generally, if not always, occurs against an odorous background. On any given inhalation, olfactory receptor neurons will be activated by features of both the target odorant and features of background stimuli. To identify a target odorant against a background therefore, the olfactory system must be capable of grouping a subset of features into an odor object distinct from the background. Our previous work has suggested that rapid homosynaptic depression of afferents to the anterior piriform cortex (aPCX) contributes to both cortical odor adaptation to prolonged stimulation and habituation of simple odor-evoked behaviors. We hypothesize here that this process may also contribute to figure-ground separation of a target odorant from background stimulation. Single-unit recordings were made from both mitral/tufted cells and aPCX neurons in urethan-anesthetized rats and mice. Single-unit responses to odorant stimuli and their binary mixtures were determined. One of the odorants was randomly selected as the background and presented for 50 s. Forty seconds after the onset of the background stimulus, the second target odorant was presented, producing a binary mixture. The results suggest that mitral/tufted cells continue to respond to the background odorant and, when the target odorant is presented, had response magnitudes similar to that evoked by the binary mixture. In contrast, aPCX neurons filter out the background stimulus while maintaining responses to the target stimulus. Thus the aPCX acts as a filter driven most strongly by changing stimuli, providing a potential mechanism for olfactory figure-ground separation and selective reading of olfactory bulb output.
引用
收藏
页码:1888 / 1896
页数:9
相关论文
共 34 条
[31]   Synaptic correlates of odor habituation in the rat anterior piriform cortex [J].
Wilson, DA .
JOURNAL OF NEUROPHYSIOLOGY, 1998, 80 (02) :998-1001
[32]   Odor specificity of habituation in the rat anterior piriform cortex [J].
Wilson, DA .
JOURNAL OF NEUROPHYSIOLOGY, 2000, 83 (01) :139-145
[33]   Configurational and nonconfigurational interactions between odorants in binary mixtures [J].
Wiltrout, C ;
Dogra, S ;
Linster, C .
BEHAVIORAL NEUROSCIENCE, 2003, 117 (02) :236-245
[34]   The role of metabotropic glutamate receptors and cortical adaptation in habituation of odor-guided behavior [J].
Yadon, CA ;
Wilson, DA .
LEARNING & MEMORY, 2005, 12 (06) :601-605