I am doing the PhD from 2013/10. My project mainly aims at investigating the role of Locus Coeruleus (LC) in the attentional set-shifting behavior on the rats. Locus Coeruleus (LC) is the primary source of norepinephrine (NE) in the forebrain. Attentional set-shifting is a cognitive process in which established stimulus reinforcement contingencies are ignored and attention is reset to respond in relation to a previously irrelevant perceptual stimulus. fMRI in humans and pharmacological studies in rats suggest that LC has a role in cognition. The few electrophysiological studies of LC unit activity during behavior in rodents and monkeys have led to the hypothesis of a role of LC in cognitive flexibility. We are testing this hypothesis by recording LC firing activity simultaneously with activity in medial prefrontal cortex (mPFC), specifically in prelimbic cortex (PL), as well as hippocampus (Hip), regions receiving LC projections and also important for cognitive flexibility. Besides, We will optogenetically stimulate or inhibit LC neurons during the set-shifting task and observe the effects of these manipulations on rat’s behavior and mPFC and Hip activities as well as their LFP coherence.