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Description: Natural sounds including all animal vocalisations have distinct temporal structure consisting of individual segments with variations over time that are either slow or fast. The ability to extract, represent, and detect an acoustic feature depends on the time window used for processing the acoustic signal. A short analysis window provides higher temporal resolution and enables quicker response while a long analysis window provides higher spectral resolution, better signal to noise ratio (SNR) which enables an accurate behavioural response. Use of optimal duration of analysis window enables the right trade-off between reaction time and accuracy of response of an animal. This aspect of auditory perception is ecologically important since fast and accurate response to acoustic stimuli is critical to the success of many animals, for instance survival depends on ability to hunt prey and avoid predators. The optimal duration of analysis window depends upon the underlying acoustic feature that needs to be processed. A slowly varying signal requires a longer analysis window while a rapidly varying signal requires a shorter analysis window. For instance in human speech, phonemes and syllables vary different and thus require different time windows. Use of different durations of analysis windows require distinct neuronal populations with appropriate time constants. A preferred time window of a given cortical area is defined as the minimum time period required to resolve two distinct acoustic events typically using the fluctuations in the neural discharge rates of that particular area. Thus different regions of the auditory brain are employed that utilize different time windows. So there exists an anatomical organisation of time window processing in auditory cortex. We aimed to identify the cortical organisation of analysis window in primates. A comparative study of this anatomical organisation of time window processing might reveal interesting similarities and differences between humans and non-human primates.