[Abstract Title]. - Society for Neuroscience

above baseline) and showed no decrement after 4 hrs (suggesting protein synthesis-dependent
“late” LTP), it nonetheless returned to baseline within 24 hrs. These data indicate LTP with
distinct characteristics can be induced with different stimulation frequencies. Moreover, different
stimulation parameters induce LTP of different durations, suggesting different patterns of
afferent activity engage distinct molecular cascades of LTP maintenance. This indicates the
diversity and versatility of LTP at a single synapse, and that distinct forms of LTP can be
induced with distinct patterns of afferent activity, even within a single synaptic population.
Disclosures: D.M. Villarreal , None; K.E. Anguiano, None; B.E. Derrick, None; F.L. Jones,
None.
Poster
238. LTD: Hippocampus and Cortex
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 238.24/D69
Topic: B.08.f. Long-term depression ( LTD )
Support: Hearing Research, Inc.
NIDCD
Sandler Translational Research postdoctoral fellowship
Jane Coffin Childs postdoctoral fellowship
Title: Conservation of net synaptic input in cortical receptive field plasticity
Authors: *R. C. FROEMKE, M. M. MERZENICH, C. E. SCHREINER;
Dept Otolaryngology, UCSF, San Francisco, CA
Abstract: Cortical synapses are modified by sensory experience and electrical activity. Synaptic
modification in vivo alters receptive fields of sensory cortical neurons, with complex dynamics
over an extended period of time. Here we used in vivo whole-cell voltage-clamp recordings to
examine the dynamics of receptive field plasticity in primary auditory cortex of adult rats,
focusing on coordination of synaptic modifications across multiple inputs and stimulus features.
Neuromodulation is required for receptive field plasticity. We used electrical stimulation of the
cholinergic nucleus basalis to enable synaptic receptive field modification of auditory cortical
neurons (Froemke et al., Nature 2007). Basalis stimulation was paired with presentation of a
sensory stimulus (pure tones of specific intensity and frequency). Before pairing, excitation and