The term macroplanning has been used to refer to the construction of semantic-conceptual structures that enable speakers to accomplish communicative goals during spontaneous speech production. One form of evidence provided as support for the existence of macroplanning are temporal cycles in speech uency. The assumption is that speakers alternate between phases of low uency, during which they prepare macroplans, and high uency, during which macroplans are executed in speech. Existing models of macroplanning suggest that temporal cycles therefore re ect a scheduling problem between processes competing for the capacity of shared resources. Time series analyses con rmed the existence of temporal cycles in spontaneous spoken discourse. In addition, evidence that topic shifts generally precede periods of increasing uency in the temporal cycle was thought to be consistent with the assumption that the cycle re ects macroplanning activity. Existing models of macroplanning are reviewed in light of these results, and problems associated with the underlying assumptions of these models are discussed.

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Deficits in cognition and motivation are common and debilitating aspects of psychiatric disorders, yet still go largely untreated. The neuropeptide oxytocin (OT) is a potential novel therapeutic for deficits in social cognition and motivation in psychiatric patients. However, the effects of OT on clinically relevant domains of non-social cognition and motivation remain under studied. The present study investigated the effects of acute and chronic (21-day) administration of subcutaneous OT (0.04, 0.2, and 1 mg/kg) in cross-species translatable operant paradigms of reward learning and effortful motivation in male and female Brown Norway (BN) rats (n=8-10/group). Reward learning was assessed using the probabilistic reversal learning task (PRLT) and effortful motivation was measured using the progressive ratio breakpoint task (PRBT). As predicted, BN rats exhibited baseline deficits in the detection of reversals of reward contingency in the PRLT relative to Long Evans (LE) rats. The two strains performed equally in the PRBT. Thirty minutes after a single OT injection (1 mg/kg), measures of both initial probabilistic learning (trials to first criterion) and subsequent reversal learning (contingency switches) were significantly improved to levels comparable with LE rats. The OT effect on switches persisted in male, but not female, BN rats 30 minutes, 24 hours, and 6 days after long-term OT administration, suggesting the induction of neuroplastic changes. OT did not affect effortful motivation at any time-point. The beneficial effects of OT on reward learning in the absence of increased effortful motivation support the development of OT as a novel therapeutic to improve cognitive functioning.

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