The ability to retrieve qualitative details or associations surrounding a past event, defined as episodic long- term memory, is essential for higher-order cognition. Previous research has suggested that different regions in the prefrontal cortex may implement encoding processes that support memory for specific items and memory for associations or relations between items. Some behavioral research has suggested that these processes might also be functionally dissociable, but this topic remains controversial. The goal pursued here is to bridge the gap between these two parallel streams of research using a combination of behavioral and neuroimaging techniques. Specifically, the proposed research will assess whether encoding processes that build relations amongst items (relational encoding) are functionally and neurally distinct from encoding processes that emphasize distinctive features of items (item-specific encoding).
Two specific aims will be addressed: 1) To test the hypothesis that item-specific and relational encoding processes make qualitatively different contributions to later episodic long-term memory; 2) To test the hypothesis that item-specific and relational processes are mediated by distinct regions of the prefrontal cortex. To test the first Aim, I propose a behavioral experiment in which participants will study word pairs using either a relational or an item- specific encoding strategy. Subsequent to encoding, memory for detailed item information and for inter-item associations will be measured in a parallel fashion. To address Aim 2, I propose to use this behavioral paradigm in an fMRI experiment in which participants will be scanned during relational and item-specific encoding of word pairs. Following scanning, memory for detailed item and inter-item memory we will tested. Brain activation will be analyzed as function of subsequent item and inter-item memory. Relevance: Impairments in the control processes that support episodic memory, as seen in psychiatric disorders such as schizophrenia, depression and attention deficit disorder have a strong negative impact on patients' quality of life. Research that examines how memory encoding processes operate in the brain can help develop more effective diagnostic and therapeutic approaches for individuals with memory disorders. ? ? ? ?
| Blumenfeld, Robert S; Parks, Colleen M; Yonelinas, Andrew P et al. (2011) Putting the pieces together: the role of dorsolateral prefrontal cortex in relational memory encoding. J Cogn Neurosci 23:257-65 |
| Ragland, John D; Laird, Angela R; Ranganath, Charan et al. (2009) Prefrontal activation deficits during episodic memory in schizophrenia. Am J Psychiatry 166:863-74 |
