Formation of memories relies on transcription of inducible genes such as immediate early genes (IEGs), but the mechanism is poorly understood. Here, IEG expression was monitored in mice following experiences with different salience and valence. Different experiences induced specific expression patterns of IEG expression. Moreover, habituation to rewarding experiences was accompanied by increasing levels of IEG expression, whereas the opposite was found with negative reinforcers, indicating that specific experiences have associated IEG 'transcriptional signatures'.