Fig. 1.

Schematic of synaptic tagging experiments. a Synaptic weight change resulting of a presynaptic extra-cellular stimulation of a weak tetanus (21 pulses at 100 Hz), b strong tetanus (3 times 100 pulses at 100 Hz), c weak tetanus in the S1 pathway (dashed line) and strong tetanus in the S2 pathway (solid line), d strong tetanus in the S2 pathway followed 1 h later by a weak tetanus in the S1 pathway. Plasticity-related-protein synthesis inhibitor is applied during a period that starts 25 min before the induction of the strong tetanus, and lasts until 1 h after the weak tetanus induction (horizontal bar). e. Same as (d) but the inhibitor is applied during a period that starts 25 min after the strong tetanus, and lasts until 1 h after the weak tetanus. See Frey and Morris (1997), Sajikumar and Frey (2004a) for details