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Self-control failures are often attributed to a lack of top-down behavioral regulation. Self-report measures of selfcontrol reflect higher-level cognitive appraisals of behavioral control and lower-level innate temperamental traits associated with reactive processes. However, few studies have examined the extent to which different aspects of self-control relate to reactive processes. Using a large sample (n = 246), we investigated whether individual differences in six self-control trait measures were predictive of low-level processing indexed by the mismatch negativity (MMN) elicited from a passive auditory oddball task. Larger MMNs are associated with greater prediction error when the input stimulus conflicts with expectation. Self-control traits were measured by effortful control, perfectionism, impulsiveness, procrastination, perceived stress, and anxiety scales. We assumed personality traits develop around innate differences in reaction to environmental changes, resulting in differential adult expressions of self-control reflected in the six traits. All but perfectionism and perceived stress correlated with MMN amplitudes: reater self-control associated with smaller MMNs; stronger negative traits associated with larger MMNs. When the correlated measures were entered into a backwards multiple regression on MMN amplitudes, procrastination and anxiety remained in the model as significant, relatively independent contributors. Procrastination may reflect a top-down modulation of underlying reactivity. Trait anxiety may reflect a basic temperament of greater reactivity to environmental change. Individuals with strong innate reactivity and weaker top-down processes may be hypervigilant to deviations from expectation, producing larger prediction errors and MMNs. Self-control failures may reflect reduced top-down control, when the balance in cortical activity favors reactive systems over the prefrontal cortex. 

Introduction: Defined as a tendency to act without thinking or considering the consequences, impulsivity may affect the ability to detect and respond to errors. However, impulsivity is a multidimensional construct with attentional, motor and non-planning components, among others. Not all aspects of impulsivity may relate to error monitoring. In this event-related potential (ERP) study we used an individual difference approach with a large sample of healthy young adults (n = 261) and the flanker task to explore what specific facets of impulsivity were predictive of error monitoring as indexed by the error-related negativity (ERN). Methods: The Barratt Impulsiveness Scale (BIS-11) was used to measure impulsivity and its subcomponents. A visual flanker task was administered to elicit the commission of errors and the associated ERN. Results: BIS-11 total scores did not correlate with ERN amplitude. Using an exploratory strategy, we first regressed scores for six previously identified components of impulsivity on the ERN, finding a significant coefficient for cognitive instability. Because internal consistency was low, we next conducted a principal component analysis of the 30 BIS-11 items; three factors emerged: planning, impetuosity and cognitive instability. When the three scale scores were regressed on ERN amplitudes, only cognitive instability ("racing thoughts") was predictive, associating greater cognitive instability with reduced ERN amplitudes. Conclusions: Increases in the cognitive instability aspect of impulsivity predicts reduced ERN amplitudes, which may be related to individual differences in the motivational salience of errors. 

Working memory (WM), the temporary maintenance of a limited amount of information in an accessible state, is required for the performance of many tasks. Studies have shown that WM demands are related to the neural processing of tasks requiring attention: Age affects the ERP components associated with WM context updating processes in the visual oddball task (P3) and semantic processing in the word-pair judgment task (N400). This study investigated whether WM capacity measured by complex span tasks mediates the effects of age on these ERPs. Younger adults (YA, n = 44, ages 18–23 yr) and older adults (OA, n = 41, ages 69–89 yr) completed operation, reading, and symmetry complex span tasks and two ERP tasks (P3/visual oddball; N400/word-pair judgment). Results showed age-related differences for all complex span tests. Principal components analysis of these tests showed a single factor for both groups, so a combined WM capacity factor score was created. Regressions of age group and WM factor score on P3 and N400 amplitudes and latencies showed that OAs had relatively lower amplitudes and longer latencies. However complex span was not related to P3 or N400 amplitudes or latencies and that result was the same for younger and older adults; that is, complex span did not mediate the age effects. WM processes indexed by the P3 and N400 components appear to be different from those elicited by complex span tasks. Attentional control processes of WM influence oddball and semantic judgement tasks more than storage components. 

We explored neural processing differences associated with aging across four cognitive functions. In addition to ERP analysis, we included task-related microstate analyses, which identified stable states of neural activity across the scalp over time, to explore whole-head neural activation differences. Younger and older adults (YA, OA) completed face perception (N170), word-pair judgment (N400), visual oddball (P3), and flanker (ERN) tasks. Age-related effects differed across tasks. Despite age-related delayed latencies, N170 ERP and microstate analyses indicated no age-related differences in amplitudes or microstates. However, age-related condition differences were found for P3 and N00 amplitudes and scalp topographies: smaller condition differences were found for in OAs as well as broader centroparietal scalp distributions. Age group comparisons for the ERN revealed similar focal frontocentral activation loci, but differential activation patterns. Our findings of differential age effects across tasks are most consistent with the STAC-r framework which proposes that age-related effects differ depending on the resources available and the kinds of processing and cognitive load required of various tasks.