Techniques
Behavioural studies
Students in the lab use a variety of behavioural tests in their projects, such as preference/avoidance assays, multi-sensory integration assays, appetitive or aversive conditioning, maze training, and manipulations of motivation. These tests allow us to investigate the evolution of learning and cognition in vertebrates. We have conducted behavioural experiments with amphibians, fishes, and even a reptile (leopard gecko). The picture shows a fire-bellied toad attending to prey stimuli displayed on a computer screen, part of a visual discrimination learning experiment.
Neuroanatomy and histology
We estimate brain size and the size of brain regions using a variety of methods to compare brains among species, ecotypes, seasons, and experimental treatments. We are also using histology techniques to compare microstructure of brains. We have also performed tract tracing of brain pathways and intracellular labelling of single/few neurons in in vitro brain preparations. A fascinating feature of the brains of anamniote vertebrates is that you can keep this organ alive in physiological solution for an extended period of time, allowing for experiments with neurotracer substances directly on the isolated brain. The detection of tracer substances on brain tissue can be done using either light or fluorescence microscopy. The micrograph on the left shows the cell body and processes of a mitral cell contained within one brain section of the salamander accessory olfactory bulb labelled by intracellular injection of biocytin. The figure on the right shows the reconstruction of a cluster of thalamic neurons in the fire-bellied toad. The lab is equipped for histology work using a variety of methods.
Functional neuroanatomy
Methods that indirectly measure brain activity to enable the study of whole brain responses are also of interest to us. Testing the effectiveness of recently developed methods (e.g. Knight et al. 2012 Cell 151:1126-1137) of functional neuroanatomy for investigations in anamniote vertebrates would complement well the other techniques used in the lab.