Event related brain potentials in elderly patients with recently diagnosed isolated systolic hypertension

Evaluation of Event-Related Potentials in Somatic Diseases - Systematic Review

Many somatic illnesses (e.g. hypertension, diabetes, pulmonary and cardiac diseases, hepatitis C, kidney and heart failure, HIV infection, Sjogren's disease) may impact central nervous system functions resulting in emotional, sensory, cognitive or even personality impairments. Event-related potential (ERP) methodology allows for monitoring neurocognitive processes and thus can provide a valuable window into these cognitive processes that are influenced, or brought about, by somatic disorders. The current review aims to present published studies on the relationships between somatic illness and brain function as assessed with ERP methodology, with the goal to discuss where this field of study is right now and suggest future directions.

The Influence of Emotional Environmental Pictures on Behavior Intentions: The Evidence of Neuroscience Technology

BACKGROUND

In recent years, researchers have been paying increasing attention to the issues of how emotions affect people's perceptions of the environment, and how they influence people's behavior or intentions to act. The purpose of this study is to explore the influences of emotions on environmental intention to act by using the neuroscience technology electroencephalography (EEG).

METHODS

A total of 70 university students participated in this study. They looked at positive and negative emotional environmental pictures and decided if they wanted to protect the environment after looking at the pictures. The participants wore an EEG cap throughout the process in order to collect their brain wave (EEG) data.

RESULTS

The analysis of variance (ANOVA) results showed that the power value of meditation was significantly higher when the participants looked at the positive than at the negative emotional environmental pictures (p < 0.001). The power value of pressure was significantly higher when the participants looked at the negative than at the positive emotional environmental pictures (p < 0.001). The power value of attention was significantly higher when the participants looked at the negative than at the emotional environmental pictures (p < 0.001).

CONCLUSIONS AND RECOMMENDATIONS

The findings showed that positive emotional environmental pictures might promote positive emotions, but will decrease the intention to act to protect the environment. In contrast, negative emotional environmental pictures will increase negative emotions, and will also increase attention and intention to act to protect the environment. Implications of the findings are discussed.

Inhibitory Control Impairment on Somatosensory Gating Due to Aging: An Event-Related Potential Study

The capacity to suppress irrelevant incoming input, termed sensory gating, is one of the most investigated inhibitory processes associated with cognitive impairments due to aging. The aim of this study was to examine the influence of aging on sensory gating by using somatosensory event-related potentials (ERPs) elicited by repetitive non-painful tactile stimulation (paired-pulsed task). Somatosensory ERPs were recorded in 20 healthy young adults and 20 healthy older adults while they received two identical pneumatic stimuli (S1 and S2) of 100 ms duration with an inter-stimulus interval of 550 ± 50 ms on both forefingers. The difference between the somatosensory ERPs amplitude elicited by S1 and S2 was computed as a sensory gating measure. The amplitude and the latency of P50, N100 and late positive complex (LPC) were analyzed as well as the source generators of the gating effect. Reduced sensory gating was found in older individuals for N100 at frontal and centro-parietal electrodes and for LPC at fronto-central electrodes. Source localization analyses also revealed a reduced current density during gating effect in the older group in frontal areas in N100 and LPC. Moreover, older individuals showed delayed latencies in N100. No significant gating effect differences were found between groups in P50. These findings suggest an age-related slowing of processing speed and a reduced efficiency of inhibitory mechanisms in response to repetitive somatosensory information during stimulus evaluation, and a preservation of processing speed and inhibitory control during early stimulus coding in aging.

Potential cognitive decline linked to angiotensin-converting enzyme gene but not hypertension: Evidence from cognitive event-related potentials

OBJECTIVES

The aims of the present study were to investigate the effect of hypertension and angiotensin-converting enzyme (ACE) genotypes on cognitive event-related potentials (ERPs), and whether the impact of ACE genotypes on P300 is related to the influence of hypertension.

METHODS

Using the Cognitive Abilities Screening Instrument (CASI), we recruited 97 mentally healthy middle-aged and older adults. Medical histories were collected, and blood pressure, ACE insertion/deletion polymorphisms and ERPs in an auditory oddball task were measured for all participants.

RESULTS

When the participants were stratified according to the presence or absence of hypertension, there were no differences in CASI score, percentage of ACE genotypes and ERPs. The subjects with the D/D homozygote displayed lower amplitude and longer latency of P300, although there were no differences in CASI score and the percentage of hypertension.

CONCLUSIONS

The subjects with the D/D genotype tended to have decreased amplitude and prolonged latency of P300 ERPs which reflected subtle cognitive impairment. There were no associations between hypertension, CASI score and P300 measurements.

SIGNIFICANCE

Using ERPs, potential cognitive decline was linked to ACE genotypes, independently of the effect of hypertension.

Impairment in preattentive processing among patients with hypertension revealed by visual mismatch negativity

Objective. Patients with hypertension show deficits in cognitive function. However, the neural mechanisms underlying the preattentive information processing in hypertensive patients are poorly understood. We seek to investigate whether hypertensive patients have impairments in preattentive information processing. Methods. We compared visual mismatch negativity (vMMN) between 15 hypertensive patients and 15 age-matched healthy controls, which was elicited by the change of visual duration randomly presented in both peripheral visual fields. In addition, the global cognitive function for all participants was assessed with Mini-Mental State Examination (MMSE). Results. The vMMN in deviant-standard comparison was observed at occipital-temporal regions. Compared with normal healthy controls, the amplitude of vMMN was significantly decreased in hypertensive patients (P < 0.05). Meanwhile, the vMMN peak latency was delayed in the hypertensive group (P < 0.05). However, the MMSE scores of patients with hypertension were not significantly different from those of controls (P > 0.05), and there was no significant correlation between the mean amplitude of vMMN and SBP, DBP, and MMSE in hypertensive individuals, respectively. Conclusions. These data indicate dysfunction of automatically change detection processing in patients with hypertension. Moreover, the changes of vMMN provide a more objective and reliable assessment for cognitive impairment in hypertensive patients.