Using EEG and local field potentials (LFPs) as an index of large-scale neural activities, research has been able to associate neural oscillations in different frequency bands with markers of cognitive functions, goal-directed behavior, and various neurological disorders. While this gives us a glimpse into how neurons communicate throughout the brain, the causality of these synchronized network activities remains poorly understood. Moreover, the effect of the major neuromodulatory systems (e.g., noradrenergic, cholinergic, and dopaminergic) on brain oscillations has drawn much attention. More recent studies have suggested that cross-frequency coupling (CFC) is heavily responsible for mediating network-wide communication across subcortical and cortical brain structures, implicating the importance of neurotransmitters in shaping coordinated actions. By bringing to light the role each neuromodulatory system plays in regulating brain-wide neural oscillations, we hope to paint a clearer picture of the pivotal role neural oscillations play in a variety of cognitive functions and neurological disorders, and how neuromodulation techniques can be optimized as a means of controlling neural network dynamics. The aim of this review is to showcase the important role that neuromodulatory systems play in large-scale neural network dynamics, informing future studies to pay close attention to their involvement in specific features of neural oscillations and associated behaviors.

Early help seeking (HS) among patients with emerging Alzheimer’s disease and related dementias (AD/ADRD) can have considerable implications for treatment course, access to clinical trials, lifestyle, and future quality of life. Previous studies in older adults suggest cognitive impairment itself does not lead people to seek help; rather, HS appears to be driven by Subjective Cognitive Decline (SCD), personality, and mood. It is possible, however, that tests used to measure objective cognition were not sensitive to detect subtle cognitive impairments that may influence HS behavior. In this study of 142 cognitively healthy older adults, we examined if utilizing cognitive tasks sensitive to preclinical AD (i.e., short term memory binding, associative memory, and susceptibility to semantic interference) revealed an independent association between objective cognition and HS, or if SCD continued to be a primary driver. Participants were assessed for HS, SCD severity, personality traits (conscientiousness and neuroticism), depressive symptoms, and demographics (age, gender, education). Partially and fully adjusted regression models were conducted to examine the association between cognitive tests and HS whilst adjusting for demographics, personality, depressive symptoms, and SCD. Associative memory was the only cognitive marker significantly worse in those who help seek (B=- 0.07, SE=0.03, p=.031); however, it did not withstand adjustment for SCD. Only increased SCD (B=0.06, SE=0.02, p=.005) and educational attainment (B=0.42, SE=0.15, p=.005) had independent associations with HS. Ongoing work is establishing possible moderators of these associations to unravel the multifaceted influences on HS and to guide strategies to increase HS in older adults with SCD.