Group Leader

Joergen Kornfeld

Connectomics of learned behaviour

Joergen Kornfeld
Group Members
  • Andreea-Maria Aldea
  • Frederico Araujo
  • Caitlin Gillespie
  • Nelson Medina
  • Anastasia Sorokina

How do animals store learned behaviours in their neuronal networks and retrieve them when performing those behaviours? It is widely believed that the connections between neurons, or synapses, are the memory substrate. The sum total of all these synaptic connections is the connectome.

Using the zebra finch songbird as a model, we investigate how song memories are stored and retrieved from the underlying brain circuits. These birds can perform, as adults, songs they practised as juveniles, similar to how humans learn language.

Schematic of a songbird brain with the song system highlighted and an image of generated neurons from this system
The circuit of the song system in a zebra finch brain.

To map these brain circuits at sufficient resolution to see synapses, we employ high-throughput 3D electron microscopy. This process generates vast amounts of image data, far more than someone could inspect manually. We therefore employ state-of-the-art deep learning techniques to infer the connectomic map and let the artificial neural networks reconstruct the real ones.

Method development is central to this effort. We collaborated with Google Research to develop flood-filling networks for automated neuron reconstruction based on our data. We also developed the first dense synaptic connectivity inference pipeline, SyConn2. These tools allow us to collect larger datasets and analyse them efficiently, making previously intractable biological questions accessible.

Our long-term goal is to mechanistically understand how a learned behaviour, the zebra finch song, is encoded in the underlying synaptic wiring patterns, and create a link between the specific behaviour of an individual and its underlying connectome.

Selected Publications

DeepFocus: fast focus and astigmatism correction for electron microscopy.Schubert PJ, Saxena R, Kornfeld JNat Commun 15(1): 948 Epub
SyConn2: dense synaptic connectivity inference for volume electron microscopy.Schubert PJ, Dorkenwald S, Januszewski M, Klimesch J, Svara F, Mancu A, Ahmad H, Fee MS, Jain V, Kornfeld JNat Methods 19(11): 1367-1370 (2022)
Learning cellular morphology with neural networks.Schubert PJ, Dorkenwald S, Januszewski M, Jain V, Kornfeld JNat Commun 10(1): 2736 (2019) Epub
High-precision automated reconstruction of neurons with flood-filling networks.Januszewski M, Kornfeld J, Li PH, Pope A, Blakely T, Lindsey L, Maitin-Shepard J, Tyka M, Denk W, Jain VNat Methods 15(8): 605-610 (2019)