Cholinergic Contributions to the Effects of Early Lead ExposureEPA Grant Number: U915393
Title: Cholinergic Contributions to the Effects of Early Lead Exposure
Investigators: Driscoll, Lori D.
Institution: Cornell University
EPA Project Officer: Michaud, Jayne
Project Period: August 1, 1998 through July 1, 2001
Project Amount: $90,000
RFA: STAR Graduate Fellowships (1998) RFA Text | Recipients Lists
Research Category: Fellowship - Psychology , Economics and Decision Sciences , Academic Fellowships
The objectives of this research project are to: (1) characterize the specific behavioral processes that underlie lead (Pb)-induced changes in explicit memory; (2) determine whether early postnatal Pb exposure produces deficits in sustained attention; and (3) assess the degree to which the cholinergic system contributes to the effects of Pb on accuracy, motivation, and motor function in both tasks.
Explicit memory was assessed in a radial arm maze with varying retention intervals (0, 4, and 8 hours) imposed halfway through the task. Long-term and short-term memory errors, as well as speed and latency measures, were recorded. Adult rats exposed to Pb from birth through weaning or chronically were compared to age-matched controls. An automated vigilance task, in which a brief light cue was presented over one of three funnel-shaped ports, was utilized in the assessment of sustained attention. The animals were food reinforced for a nose poke into the funnel under the light, which appeared after an unpredictable delay (0, 3, 6, or 9 seconds) and remained illuminated for an unpredictable cue duration (200, 400, or 700 milliseconds). Responses made prior to the light presentation were considered incorrect, providing a measure of inhibitory control. Subjects in the sustained attention task consisted of adult rats exposed to Pb from birth through weaning and controls.