This book describes the effect of odor
learning on brain circuitry. For the research
described in this book, rats learned to distinguish
between pairs of odors. The results show that
olfactory-discrimination learning in the rat is
accompanied by a transient increase in dendritic
spine density along apical dendrites of the primary
olfactory cortex (the Piriform cortex) and
hippocampal neurons. The learning-related increase
in spine density in neurons from trained rats
probably reflects a net increase in the number of
excitatory synapses in the piriform cortex and
hippocampus following olfactory rule learning. This
increase is accompanied by a series of modifications
in the geometrical parameters of dendritic spines in
the piriform cortex and by biochemical changes in
cell adhesion molecules. These changes may reflect
synaptic remodeling or creation of new neurons that
could underlie the establishment of odor rule-
learning. The modifications described here combine
to create a state in which the rat remembers to
associate specific odors with a reward.
learning on brain circuitry. For the research
described in this book, rats learned to distinguish
between pairs of odors. The results show that
olfactory-discrimination learning in the rat is
accompanied by a transient increase in dendritic
spine density along apical dendrites of the primary
olfactory cortex (the Piriform cortex) and
hippocampal neurons. The learning-related increase
in spine density in neurons from trained rats
probably reflects a net increase in the number of
excitatory synapses in the piriform cortex and
hippocampus following olfactory rule learning. This
increase is accompanied by a series of modifications
in the geometrical parameters of dendritic spines in
the piriform cortex and by biochemical changes in
cell adhesion molecules. These changes may reflect
synaptic remodeling or creation of new neurons that
could underlie the establishment of odor rule-
learning. The modifications described here combine
to create a state in which the rat remembers to
associate specific odors with a reward.