Humboldt-Universität zu Berlin - Behavioural Physiology

Neural circuits

Neural circuits processing behaviorally meaningful signals in weakly electric fish

Livio_Oboti_corpped.jpgLivio Oboti, Dr.

I am interested in studying how social information is processed by higher order brain circuits in order to establish adaptive behavioral interactions. My recent work provided evidence for a role of the amygdala in modulating the early stages of social odor processing in rodents (Mus musculus) through feedback projections to the olfactory bulb (Oboti et al., 2018; Figure 1).






Figure1 - Tracing of amygdala projections.png















Figure 1: (a) Tracing of amygdala projections (PmCo) to olfactory bulb (AOB-GC) via a CamKIIa-specific virus. (b) Layout of the recording experiments: electrical stimuli (E) were targeted onto the vomeronasal nerve (VN), while optogenetic stimuli (O) were delivered onto the granule cell (GC) layer. Mitral cell (MC) firing rate was recorded in cell-attached mode (the pie chart shows the response types). (c) Dual activation of PmCo feedback and VN mediated incoming inputs enhances MC responses to VN inputs (EO vs E).


Currently I am studying the functional development of homologous top-down feedback circuits within the fish brain (sp. Apteronotus leptorhynchus). Weakly electric fish can generate electric fields (through electric organ discharges, or EODs) through which they navigate the environment - seeking prey, locating  objects or other conspecifics - and communicate (Krahe & Maler, 2014; Figure 2).


Figure - 2_Weakly electric fish fields.png

Figure 2: (a) Weakly electric fish generate electric fields around their body through electric organ discharges (EOD). Objects (green sphere) near the fish perturb the electric field, creating local amplitude modulations (AM) of the EOD. (b) The summation of two or more EODs occurring during social interactions creates a periodic AM (red trace).


Due to the simple and stereotypical nature of their electric signals (EOD frequency and amplitude modulations called chirps; Figure 3), weakly electric fish are well suited as model organisms to address even complex functional questions regarding brain physiology.


Figure2-EOD chirps- Apteronotus leptorynchus.png










Figure 3: Excerpt of a spectrogram showing the EODs of two interacting fish (the horizontal traces correspond to signals produced by two different individuals having different EOD frequencies, one below 0.9 kHz and one slightly above). Chirps are very fast frequency modulations of the EOD that are produced during social interactions.



  1. Oboti L, Russo E, Tran T, Durstewitz D, Corbin J, 2018. Amygdala Corticofugal Input Shapes Mitral Cell Responses in the Accessory Olfactory Bulb. eNeuro. 5:ENEURO.0175-18.2018.

  2. Krahe R, Maler L (2014). Neural maps in the electrosensory system of weakly electric fish. Curr Opin Neurobiol. 24:13-21.


Complete list of my publications: