Related Experiment Videos
A nitric oxide agonist stimulates consolidation of long-term memory in the 1-day-old chick
N S Rickard1, K T Ng, M E Gibbs
1Department of Psychology, La Trobe University, Bundoora, Victoria, Australia.
Insights
Nitric oxide synthesis is critical for long-term memory consolidation in chicks. Administering sodium nitroprusside after weak training trials promoted memory formation, unlike saline.
Area of Science:
- Neuroscience
- Behavioral Neuroscience
- Molecular Biology
Background:
- Memory consolidation involves distinct stages, with long-term memory dependent on protein synthesis.
- Weakly reinforced learning trials in chicks typically fail to establish long-term memory.
Purpose of the Study:
- To investigate the role of nitric oxide synthesis in the consolidation of long-term memory in young chicks.
- To determine if enhancing nitric oxide synthesis can rescue long-term memory formation after weak training.
Main Methods:
- Utilized a passive avoidance task in 1- to 2-day-old chicks.
- Administered sodium nitroprusside (a nitric oxide donor) or saline intracranially after weak training trials.
- Assessed memory formation and consolidation.
Main Results:
- Chicks trained with strong reinforcement formed a 3-stage memory trace, with the final stage requiring protein synthesis.
- Weak training alone did not typically result in long-term memory.
- Intracranial administration of sodium nitroprusside immediately after weak training promoted long-term memory formation, while saline did not.
Conclusions:
- Nitric oxide synthesis plays a critical role in the consolidation of long-term memory in chicks.
- Enhancing nitric oxide synthesis can facilitate the formation of long-term memory even after weakly reinforced learning experiences.
Abstract:
Chicks, age 1 to 2 days, that have been trained on a passive avoidance task with a strongly reinforced training trial yield a memory trace that is composed of 3 behaviorally and pharmacologically distinguishable stages, with the final long-term memory stage being dependent on protein synthesis. In contrast, chicks trained with a weakly reinforced learning trial typically do not demonstrate this final stage of memory. Sodium nitroprusside 150 microM intracranially administered immediately after a weak training trial promoted the formation of long-term memory, whereas saline did not. The results suggest that nitric oxide synthesis is either itself critical or stimulates other processes that are critical for the consolidation of long-term memory.