Effects of Appetitive, Pre-Exposed, and Novel Distracters on Interval Timing Behavior: Role of Nomifensine Within the Prelimbic Cortex

Poor attentional focus harms the estimation of time within the seconds-to-minutes range, i.e. interval timing. Interval timing behavior is related to several cognitive functions including perception of the passage of time, decision making, and to memory processes. Harmful delays in timing are caused by distractions of attention, within the timing task in the form of novel, or familiar distracters, which may or may not have been previously conditioned. The purpose of this dissertation was to explore how attention to novel or familiar distractions within the timing task can be altered using catecholamine reuptake blocker nomifensine. The experiment in Chapter 3, found group differences due to the differences in the conditioning to the noise stimulus, i.e. the familiarity to the stimulus altered the resulting time delays behaviors of the rats. Additionally, the results from Chapter 3 show that nomifensine, a medication that inhibited the reuptake of dopamine and norepinephrine, was differentially effective at reducing the time delays resulting from the presentation of the noise distracter within a peak interval timing paradigm. The fact that group differences exist due to the conditioning setup, and there appears to be differences in the sensitivity to the drug, indicates that drugs that alter attention to timing involve complex interactions within the timing circuit to catecholamine modulation