With increasing knowledge about information processing in the intact brain, it has become evident how strongly social factors influence computations and storage of information. To learn more about the underlying processes, we are studying the influence of social interactions between mice and their pups on learning behavior. Mice collect their pups when these have fallen out of the nests and emit vocalizations to indicate that they are in need of help.
We are using this pup-retrieval behavior to study the impact of pup calls onto the structure and function of auditory cortex neurons in mothers and foster mothers. Specifically, we investigate how cortical circuit wiring and neural network activity changes during acquisition of this parental care behavior. Finally, both datasets will be brought together to generate a coherent interpretation of the relationship between structural and functional plasticity during natural parenting behavior.
We first analyze changes in synaptic fine structures during the transition from a naïve to a parental animal. To this end, we engage chronic structural two-photon imaging of the very same dendritic spines and axonal boutons over a time period of 2-3 months before, during and after acquisition of parenthood. We then quantitatively analyze changes in synaptic structures to better understand the structural dynamics accompanying the acquisition of parental behavioral patterns.
To elucidate the functional manifestation of such structural changes, we functionally analyze auditory cortex neurons over the same time course using two-photon microscopy of calcium activity. Here, we are particularly interested in the functional changes of individual neurons during acquisition of parental behavior and how these changes shape higher-level activity patterns of neuronal populations to adapt to the behavioral changes.
The functional experiments described above were performed to obtain high-resolution data under very controlled experimental conditions. However, parental care is a highly natural behavior. Therefore, we are complementing our controlled and artificial experiments by a more open experimental approach as close as possible to the real natural environment. To this end, we use miniaturized head-mounted microscopes and optogenetics providing optical access to auditory cortex neurons under awake and unrestrained conditions. This enables us to record and manipulate and understand neural activity patterns while the animal is retrieving pups under almost natural conditions.