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A burst-based "Hebbian" learning rule at retinogeniculate synapses links retinal waves to activity-dependent refinement.

Butts DA, Kanold PO, Shatz CJ - PLoS Biol. (2007)

Bottom Line: Using perforated patch recordings from neurons in LGN slices during the period of eye segregation, we examine how such burst-based activity can instruct this refinement.It is consistent with "Hebbian" development thought to exist at this synapse, and we demonstrate computationally that such a rule can robustly use retinal waves to drive eye segregation and retinotopic refinement.Thus, by measuring plasticity induced by natural activity patterns, synaptic learning rules can be linked directly to their larger role in instructing the patterning of neural connectivity.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, United States of America. dab2024@med.cornell.edu

ABSTRACT
Patterned spontaneous activity in the developing retina is necessary to drive synaptic refinement in the lateral geniculate nucleus (LGN). Using perforated patch recordings from neurons in LGN slices during the period of eye segregation, we examine how such burst-based activity can instruct this refinement. Retinogeniculate synapses have a novel learning rule that depends on the latencies between pre- and postsynaptic bursts on the order of one second: coincident bursts produce long-lasting synaptic enhancement, whereas non-overlapping bursts produce mild synaptic weakening. It is consistent with "Hebbian" development thought to exist at this synapse, and we demonstrate computationally that such a rule can robustly use retinal waves to drive eye segregation and retinotopic refinement. Thus, by measuring plasticity induced by natural activity patterns, synaptic learning rules can be linked directly to their larger role in instructing the patterning of neural connectivity.

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The Effects of Retinal Waves Are Cumulative over TimeTwo examples of experiments demonstrating the cumulative effect of two opposing stimulation protocols: (A) −1,100-ms latency (lat.) pairing followed by zero-latency pairing; and (B) −300-ms latency pairing followed by −2,100-ms latency pairing. Horizontal blue lines represent the mean EPSC size, and vertical green and red boxes demonstrate the duration of the stimulation protocol.
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pbio-0050061-g005: The Effects of Retinal Waves Are Cumulative over TimeTwo examples of experiments demonstrating the cumulative effect of two opposing stimulation protocols: (A) −1,100-ms latency (lat.) pairing followed by zero-latency pairing; and (B) −300-ms latency pairing followed by −2,100-ms latency pairing. Horizontal blue lines represent the mean EPSC size, and vertical green and red boxes demonstrate the duration of the stimulation protocol.

Mentions: Activity-dependent retinogeniculate refinement occurs over several weeks in most species, meaning that the gradual strengthening of some synapses and elimination of most others is a cumulative effect of many thousands of individual retinal waves. Figure 5 provides evidence that the effects of retinal waves are indeed cumulative. These two examples show sequential induction of opposing plasticity with stimulation protocols separated by an hour: in the first example, a long-lasting weakening is followed by strengthening (Figure 5A); the reverse occurs in the second example (Figure 5B). These examples also provide another demonstration that the particular burst latency—rather than the mere presence of bursts—is responsible for determining the sign of plasticity.


A burst-based "Hebbian" learning rule at retinogeniculate synapses links retinal waves to activity-dependent refinement.

Butts DA, Kanold PO, Shatz CJ - PLoS Biol. (2007)

The Effects of Retinal Waves Are Cumulative over TimeTwo examples of experiments demonstrating the cumulative effect of two opposing stimulation protocols: (A) −1,100-ms latency (lat.) pairing followed by zero-latency pairing; and (B) −300-ms latency pairing followed by −2,100-ms latency pairing. Horizontal blue lines represent the mean EPSC size, and vertical green and red boxes demonstrate the duration of the stimulation protocol.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC1808114&req=5

pbio-0050061-g005: The Effects of Retinal Waves Are Cumulative over TimeTwo examples of experiments demonstrating the cumulative effect of two opposing stimulation protocols: (A) −1,100-ms latency (lat.) pairing followed by zero-latency pairing; and (B) −300-ms latency pairing followed by −2,100-ms latency pairing. Horizontal blue lines represent the mean EPSC size, and vertical green and red boxes demonstrate the duration of the stimulation protocol.
Mentions: Activity-dependent retinogeniculate refinement occurs over several weeks in most species, meaning that the gradual strengthening of some synapses and elimination of most others is a cumulative effect of many thousands of individual retinal waves. Figure 5 provides evidence that the effects of retinal waves are indeed cumulative. These two examples show sequential induction of opposing plasticity with stimulation protocols separated by an hour: in the first example, a long-lasting weakening is followed by strengthening (Figure 5A); the reverse occurs in the second example (Figure 5B). These examples also provide another demonstration that the particular burst latency—rather than the mere presence of bursts—is responsible for determining the sign of plasticity.

Bottom Line: Using perforated patch recordings from neurons in LGN slices during the period of eye segregation, we examine how such burst-based activity can instruct this refinement.It is consistent with "Hebbian" development thought to exist at this synapse, and we demonstrate computationally that such a rule can robustly use retinal waves to drive eye segregation and retinotopic refinement.Thus, by measuring plasticity induced by natural activity patterns, synaptic learning rules can be linked directly to their larger role in instructing the patterning of neural connectivity.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, United States of America. dab2024@med.cornell.edu

ABSTRACT
Patterned spontaneous activity in the developing retina is necessary to drive synaptic refinement in the lateral geniculate nucleus (LGN). Using perforated patch recordings from neurons in LGN slices during the period of eye segregation, we examine how such burst-based activity can instruct this refinement. Retinogeniculate synapses have a novel learning rule that depends on the latencies between pre- and postsynaptic bursts on the order of one second: coincident bursts produce long-lasting synaptic enhancement, whereas non-overlapping bursts produce mild synaptic weakening. It is consistent with "Hebbian" development thought to exist at this synapse, and we demonstrate computationally that such a rule can robustly use retinal waves to drive eye segregation and retinotopic refinement. Thus, by measuring plasticity induced by natural activity patterns, synaptic learning rules can be linked directly to their larger role in instructing the patterning of neural connectivity.

Show MeSH