Ready for Action! When the Brain Learns, Yet Memory-Guided Behavior Does Not Follow

The ability to use memory for action is critical for everyday life, such as for remembering which alarm signals danger. Although research suggests that memory for past events influences how we respond to events in the present, the magnitude of behavioral benefit varies and can even be absent. How is it that the brain learns, yet the learning does not influence memory-guided action? In this thesis, I show that 1) not all learned memory representations are usable for behavior and 2) those that are usable for behavior are supported by distinct neural mechanisms during retrieval. Study 1 demonstrates that learning and behavioral expression of learning are separable and differentially affected by attention. Studies 2 and 3 provide further evidence that memory-guided behavior is supported by distinct neural substrates. Specifically, Study 1 leveraged high-density electroencephalography (EEG) and revealed a striking brain-behavior dissociation. Learning was observed neurally in two attention conditions. However, only one condition, in which attention was directed to the task-relevant object at learning, led to a memory-guided behavioral benefit at retrieval. Further, these behaviorally accessible memories were accompanied by an implicit neural memory component that correlated with the degree of response preparation, but not with response execution. In Study 2, I conducted a systematic review and a meta-analysis and demonstrated that fronto-parietal attention and control networks are critical for memory-guided behavior. Study 3 empirically validated this working model, using time-frequency source localization. Specifically, I showed that, in addition to fronto-parietal networks, memory-guided behavior is accompanied by anterior temporal lobe activity that scales with the magnitude of behavioral benefit. Together, the results of the presented studies suggest that 1) attention at learning affects memory accessibility and guided behavior at retrieval and 2) accessible memories that guide behavior are supported by distinct temporal and fronto-parietal networks and implicit neural memory that triggers response preparation.

Department dc:contributor.department

Psychology

Year dc:date.issued

2023

Author dc:creator

• Fischer, Manda

Advisors dc:contributor.advisor

• Alain, Claude
• Moscovitch, Morris

• Attention
• Electroencephalography
• Lateralized readiness potential
• Long-term memory
• Memory-guided attention
• Response preparation

Handle dc:identifier.uri

http://hdl.handle.net/1807/130099

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/130099