Populationskodierung natürlicher Stimuli

• Applicant: Professor Dr. Nicholas A. Lesica
• Subject Area: Cognitive, Systems and Behavioural Neurobiology
• Term: from 2009 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 98854254

One of the fundamental goals of sensory neuroscience is to understand exactly how information about the outside world is represented in brain activity. Cracking this ‘neural code’ is essential for understanding how the brain makes decisions and determines behavior, as well as for the development of clinical strategies for replacing brain function lost to trauma or disease. Despite tremendous advances in our understanding of sensory function over the past several decades, the neural representation of complex stimuli typical of the natural environment remains a mystery. This gap in our understanding can be attributed to two complex properties of sensory systems that are important in the natural environment, but are not addressed in typical laboratory experiments involving recordings of the responses of a single neuron to simple stimuli: (1) the response properties of sensory neurons are not static, but are constantly adapted to match the current statistical properties of the stimulus and (2) the representation of complex stimuli is not confined to the response of a single neuron, but is distributed across the responses of a highly interconnected population. With my research group, I plan to study these complex properties in the mammalian auditory system, specifically in the inferior colliculus (IC) of the auditory midbrain. We will record the responses of small populations of neurons simultaneously during the presentation of complex natural stimuli and we will characterize the response properties of these neurons using a variety of system identification, signal processing, and information theoretic techniques. We will also use these experimental results to develop a model that incorporates the effects of adaptation and population interconnectivity in predicting auditory responses to natural stimuli. The results of this investigation will provide fundamental information about the processing of complex sounds and will provide an important step toward elucidating the true neural code.

• DFG Programme: Independent Junior Research Groups
• International Connection: United Kingdom