different between the experimental groups, (B) Swim distance was not significantly different between the experimental groups, while (C) Swim speed was lower in TLR4 antagonist infused mice. (D) Path efficiency was significantly higher in TLR4-antagonist infused mice compared with aCSF infused mice at 48 hours after training (E) Mice implanted with osmotic pumps that infuse either aCSF (n = 10) or TLR4 antagonist (n = 10) were tested in an elevated plus maze. Mice were place in the maze for 5 minutes, and time spent in the open and closed arms was measured. TLR4 antagonist infused mice show altered anxiety response compared with aCSF infused mice (F) Mice implanted with osmotic pumps that infuse either aCSF (n = 10) or TLR4 antagonist (n = 10) were tested in an open field arena. Mice were place in the center of the arena for 15 minutes, and time spent in the center versus the periphery of the arena was measured. TLR4 antagonist infused mice show altered anxiety response compared with aCSF infused mice (G) Weight of mice following surgical procedure and during the 4 weeks in which the pumps infused aCSF or TLR4 antagonist into their lateral ventricles. Both experimental groups accumulated similar weights during the month of behavioral tasks. (TIF) Figure S3 TLR4 expression had no impact on motiva- tion, vision or motor function in spatial tasks. Mice of the following interventions were placed in the water maze while the platform was visible, and were allowed to reach the platform References 1. Kawai T, Akira S (2007) Signaling to NF-kappaB by Toll-like receptors. Trends Mol Med 13: 460–469. 2. Klune JR, Dhupar R, Cardinal J, Billiar TR, Tsung A (2008) HMGB1: endogenous danger signaling. Mol Med 14: 476–484. 3. Takeda K, Akira S (2004) TLR signaling pathways. Seminars in immunology 16: 3–9. 4. Maezawa I, Zaja-Milatovic S, Milatovic D, Stephen C, Sokal I, et al. 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