Mission:
Our mission is (1) to understand some of the computations that occur in
the early stages of sensory processing by neural circuits, and (2) to
describe the cellular, synaptic, and circuit mechanisms underlying
these computations.
 Approach: We use the
brain of the fruit fly Drosophila
to investigate these
questions. This tiny brain contains only ~100,000 neurons, and many
individual neurons are uniquely identifiable across flies. Moreover,
the powerful genetic toolbox of this organism provides a unique
combination of tools for labeling and manipulating neural circuits. Because some of the fundamental
problems of early sensory processing are likely to be common to all
species, we believe that some of the lessons we learn from this simple
brain will provide clues to understanding similar problems in more complex
brains.
Questions:
We
are studying several different regions of the Drosophila
brain, with a particular emphasis on the olfactory and auditory
systems. Our work focuses on a few key questions:
- How are odors and
sounds represented in these brain regions?
- How are these
representations reformatted (or "transformed") as they move from one
brain region to
another?
- What specific circuit,
cellular, and synaptic mechanisms shape these transformations
- How do the properties
of early sensory representations correlate with behavioral responses to
these sensory stimuli?
Techniques:
We
primarily use electrophysiological techniques (patch clamp
recording and extracellular
recording) to
record the activity of individual identified neurons in vivo.
To complement these
electrophysiological techniques, we use a
variety of genetic tools:
- We use the Gal4/UAS
system to specifically label small subsets of
neurons in the fly brain with fluorescent markers. This allows us to
target our recording electrodes specifically to these neurons.
- We image patterns of
activity in identified neurons
by expressing a genetically-encoded calcium sensor in these neurons
under Gal4/UAS control.
- We trace neural circuits by expressing genetically-encoded photoactivatable fluorophores under
Gal4/UAS control and photoactivating in specific regions of interest.
- We
use genetic tools to perturb patterns of electrical activity
in neural circuits by manipulating expression of
specific ion
channels, receptors, or neurosecretory molecules.
Finally,
we are devising sensitive behavioral paradigms for assessing sensory
perception in individual flies. By comparing the impact of specific
genetic manipulations on
both neural activity and behavior, we aim to understand how
patterns of electrical activity in the brain correspond to sensory
perceptions.
To learn about our recent discoveries, we invite you to browse some publications
from the lab.
|
