Undergraduate Theses and McNair Projects

McNair Scholar Project
Author: Heather Coulter (2003)
Title: Neural Correlates of Retrieval Processes in Prospective Memory
Supervising Faculty: Ed DeLosh
Major Purpose: Prospective memory (PM), often referred to as memory for intentions, is memory for actions to be performed in the future. In recent years the cognitive processes involved in prospective memory have been researched extensively, however the neural mechanisms involved in complex PM tasks are still not well understood. Studies of prospective memory using event related potentials (ERPs) have consistently revealed several modulations related to the realization of intentions, including an N300 associated with detection of a PM cue; a positivity over the parietal region peaking between 600 and 700 ms; and a frontal slow wave beginning approximately 500 ms after the onset of the PM cue. Due to the similarity in the time course and topography of the parietal positivity to that of the old-new recognition effect often associated with the recovery of information from episodic memory (e.g. Rugg, 1995), it has been suggested that this component may reflect the activity of the same neural processes involved in retrospective memory retrieval. It has also been suggested that the parietal positivity may be a neural correlate of an automatic associative process that supports the non-strategic retrieval of an intention from memory when a cue is detected (West & Ross-Munroe, 2002; Guynn et al., 2001). However, previous studies manipulating retrieval variables such as number of intentions have failed to elicit modulations of this component (cf. West et al., 2003). The present study used ERPs to investigate the retrieval of intentions from memory by manipulating the extent to which a PM cue is associated with the correct response. If parietal positivity reflects the automatic associative process, it is expected that the level of association between the PM cue and its response will modulate this component.

Undergraduate Honors Thesis
Author: Kristina Legget (2003)
Title: Thought Suppression and Its Effect On Subsequent Memory Performance
Supervising Faculty: Ed DeLosh
Major Purpose: Some studies have found that the act of suppressing one’s thoughts leads to those thoughts becoming more prevalent (Rassin & Diepstraten, 2003; Rassin & Merckelbach, 2001), but others have found that thought suppression can lead to the inhibition of those thoughts on later memory tests (Anderson & Green, 2001; Levy & Anderson, 2002). The present experiment used Anderson and Green’s think/no-think procedure to examine the effect of thought suppression on subsequent memory performance. Participants were instructed to suppress the second word of memorized word pairs when shown the first word of the pairs, and then their memory for the suppressed words was tested on a cued recall test. Past research using this method showed that recall was significantly reduced for suppressed words than non-suppressed words and researchers have suggested that this reflects inhibition of the suppressed items (Anderson & Green, 2001). The present experiment attempts to replicate these findings and also employs a category exemplar generation task to determine whether inhibition acts on the specific association between the words of the word pairs or acts on the representation of the suppressed word itself.

Undergraduate Thesis
Author: Judi A. Wood (2002)
Title: Aging and Motor Performance in Planning and Executing Motor Actions
Supervising Faculty: Ben Clegg
Abstract: Older adults, ranging in age from 62 years to 88 years, and younger adults, ranging in age from 18 years to 26 years, performed target acquisition tasks. The hand-to-target tasks were performed using both linear tapping tasks and sequential tapping tasks. The linear and sequential tasks were performed using both real movements and imagined movements. Older adults showed similar results to younger adults with the linear tapping task. Whereas, with the sequential task, the older adults showed a greater decrease in the ability to produce sequential movements, although planning remained similar. Older adults show a decline in the ability to execute a series of motor actions with age.

Undergraduate Honors Thesis
Author: Andrea M. Ploucher (2001)
Title: The Implicit Learning of Grammatical Concepts
Supervising Faculty: Ben Clegg, Carol Seger
Abstract: It has been suggested that implicit learning involves the acquisition of the rules underlying complex stimuli, without conscious awareness. This thesis looks at the differences between implicit and explicit learning, motor skills learning, perceptual learning, and conceptual learning. In this experiment, participants were asked to repeat three word sentences aloud. Three possible rules were used: Subject-Object-Verb (SOV), Subject-Verb-Object (SVO), and Verb-Subject-Object (VSO). Participants were told that sentences in red ink followed a rule (Explicit Condition). Unbeknownst to participants, sentences presented in black ink also followed rules (Implicit Condition). Evidence for learning, indexed by faster reading times, was found in the implicit condition. In a structure reconstruction task given afterwards, English speaking participants tended to revert back to the SVO order. This study suggests that implicit learning of rules using actual words is abstract since performance improvements generalize beyond the actual exemplars encountered.