HTR1A and Anxiety: Consequently, in 5-HT1A(-/-) knockout mice this AR PN/IN values are already elevated in naïve conditions and do not further increase in anxiety (1A-ko naïve 5.53±0.42 1A-ko anxiety 4.2±0.18, p = 0.291)(Fig 2E).This would suggest that probably enhanced anxiety levels in 1A-ko and Wt mice is triggered by a change in cortical E/I balance.