The brain is a complex adaptive system. Abstractions offering parsimonious explanations and oversimplifications become essential in characterizing certain aspects of this multi-scale system. However, it is critical that a whole-some understanding of this complex system isn’t stifled by such oversimplifications.

A central theme of research in this laboratory is that complexity is an essential device of evolution towards achieving physiological robustness. From this perspective, complexity is embraced as the lynchpin that drives robustness of the nervous system, rather than being shunned as an inconvenience that makes analyses difficult. Work in this laboratory focuses on remedying certain historical oversimplifications in single-neuron and network physiology:

1.     Oversimplification: Neurons are simple algebraic summation units with a threshold nonlinearity.

Remedy: Active dendrites bestow complex functional capabilities upon single neurons.

2.     Oversimplification: Neural circuits are made of repeating homogeneous computational units.

Remedy: Neural circuits manifest several forms of heterogeneities (intrinsic, synaptic, structural, and afferent), which play crucial physiological roles.

3.     Oversimplification: Learning and memory in biological systems is accomplished exclusively through synaptic changes.

Remedy: Biological plasticity is ubiquitous and is not limited to synapses. Ubiquitous plasticity, however, does not mean arbitrary plasticity. There are strong constraints on how different forms of plasticity interact towards achieving stable continual learning.

4.     Oversimplification: There is a unique solution to how biological learning is accomplished, and our goal is to find that solution.

Remedy: Complexity in a system is characterized by several functionally specialized subsystems that show a high degree of functional integration when they interact with each other. An important characteristic of complex biological systems is degeneracy, the ability of structurally different subsystems to yield the same functional outcome. Degeneracy is ubiquitous across all scales of the nervous system.

5.     Oversimplification: Extracellular local field potentials exclusively reflect chemical synaptic activation.

Remedy: Several sub- and supra-threshold active dendritic channels and other transmembrane currents, including those activated by gap junctional (electrical synaptic) inputs, also contribute to local field potentials.

6.     Oversimplification: Glial cells are glue.

Remedy: Glial cells are actively involved in information processing, plasticity, and learning.

We employ electrophysiological, imaging, theoretical, and computational tools towards remedying these and other oversimplifications.