Endogenous Event-related Potentials Research Articles

Using 6-CIT, P300 encephalography, and pro-inflammation assessments for screening age-related cognitive decline and exploring associated risk factors in Egyptian elderly

BackgroundThe elderly population is suffering from many mental health problems that are aggravated as a matter of age and cognitive decline is a serious one of them. The aim of the present work is to screen the cognitive performance among a sample of Egyptian elderly volunteers and to investigate the associated risk factors.ResultsA sample of 88 elderly volunteers from both genders was enrolled in the study according to the specified eligibility criteria after signing the approval consent. Medical history and socio-demographic data were collected from all participants in addition to basic clinical examination. Cognitive performance was assessed using the 6-Item Cognitive Impairment Test (6-CIT) while the endogenous event-related potentials (ERP) was measured using P300. The inflammatory biomarkers; TNF-α and COX-2 levels were assessed in serum using ELISA technique in addition to gene expression of TNF-α, PPAR-γ and CD-36 exploration using qRT-PCR. About half (51%) of the sample under investigation showed cognitive problems with scores on the 6-CIT exceeding the normal level. TNF-α serum levels showed positive correlation with P300 latency and correlated negatively with P300 reaction time. Furthermore, serum COX-2 levels correlated positively with P300 reaction time and negatively with P300 amplitude.ConclusionThe study population is showing early signs of cognitive decline that invites attention to the importance of spreading preventive measures against further deterioration. Inflammatory biomarkers under investigation and 6-CIT are suggested to be used in prediction of early stages of cognitive decline among the elderly population.

Event detection in single trial EEG during attention and memory related task

P300 is an endogenous event related potential (ERP) elicited by a rare or significant visual stimulus and is widely preferred in brain computer interface (BCI) to assess the cognition level of the subject. Many researchers contribute to P300 estimation as this signal is of very low strength in background electroencephalogram (EEG) activity. This paper proposes a novel signal processing algorithm to detect the P300 event in a single trial EEG acquired from midline electrode sites in oddball paradigm to evaluate attention and memory related tasks of subjects. The algorithm incorporates wavelet combined adaptive noise canceller followed by ensemble and moving averager. Time domain analysis shows the localisation of ERP around 300 ms for target stimuli attended by the subjects. The short-time Fourier transform (STFT) analysis shows strong theta activity associated to memory related task. Thus, the proposed algorithm is efficient in detecting the P300 with higher correlation coefficient of 0.82 (average) compared to other existing methods.

Event detection in single trial EEG during attention and memory related task

P300 is an endogenous event related potential (ERP) elicited by a rare or significant visual stimulus and is widely preferred in brain computer interface (BCI) to assess the cognition level of the subject. Many researchers contribute to P300 estimation as this signal is of very low strength in background electroencephalogram (EEG) activity. This paper proposes a novel signal processing algorithm to detect the P300 event in a single trial EEG acquired from midline electrode sites in oddball paradigm to evaluate attention and memory related tasks of subjects. The algorithm incorporates wavelet combined adaptive noise canceller followed by ensemble and moving averager. Time domain analysis shows the localisation of ERP around 300 ms for target stimuli attended by the subjects. The short-time Fourier transform (STFT) analysis shows strong theta activity associated to memory related task. Thus, the proposed algorithm is efficient in detecting the P300 with higher correlation coefficient of 0.82 (average) compared to other existing methods.

Probing the relationship between late endogenous ERP components with fluid intelligence in healthy older adults

The world population is rapidly aging, bringing together the necessity to better understand the advancing age. This characterization may be used to aid early diagnosis and to guide individually-tailored interventions. While some event-related potential (ERP) components, such as the P300 and late positive complex (LPC), have been associated with fluid intelligence (Gf) in young population; little is known whether these associations hold for older people. Therefore, the main goal of this study was to assess whether these ERP components are associated with Gf in the elderly. Fifty-seven older adults performed a continuous performance task (CPT) and a visual oddball paradigm while EEG was recorded. Participants were divided into two groups, according to their performance in the Raven’s Advanced Progressive Matrices test: high-performance (HP) and low-performance (LP). Results showed that the HP group, compared to the LP group, had higher LPC amplitudes in the CPT and shorter P300 latencies in the oddball task, highlighting the role of ERP components as a potential electrophysiological proxy of Gf abilities in the elderly.

\u201cHit the missing stimulus\u201d. A simultaneous EEG-fMRI study to localize the generators of endogenous ERPs in an omitted target paradigm

Event-Related Potentials (ERPs) occurring independently from any stimulus are purely endogenous (emitted potentials) and their neural generators can be unequivocally linked with cognitive processes. In the present study, the subjects performed two similar visual counting tasks: a standard two-stimulus oddball, and an omitted-target oddball task, characterized by the physical absence of the target stimulus. Our investigation aimed at localizing the neural sources of the scalp-recorded endogenous/emitted ERPs. To optimize the source localization, the high temporal resolution of electrophysiology was combined with the fine spatial information provided by the simultaneous recording of functional magnetic resonance (fMRI). Both tasks identified two endogenous ERP components in the 300 to 520 ms interval. An earlier component, pP2, showed a bilateral generator in the anterior Insula. A later P3 component (P3b) was generated bilaterally in the temporal-parietal junction, the premotor and motor area and the anterior intraparietal sulcus (this latter one only in the standard oddball). Anticipatory slow waves (beginning 900 to 500 ms pre-stimulus), also of endogenous nature, were produced by the inferior and middle frontal gyrus and the supplementary and cingulate motor areas. Our protocol disentangled pre- from post-stimulus fMRI activations and provided original clues to the psychophysiological interpretation of emitted/endogenous ERPs.

F110. Using brain fingerprinting in the detection of concealed information in Egyptians

Introduction Brain fingerprinting is a forensic science technique that uses electroencephalography (EEG) to determine whether specific information is stored in a subject’s brain. It does this by measuring electrical brainwave responses to pictures that are presented on a computer screen; P300 wave is a specific event-related potential (ERP) component that has the potential for detecting concealed information in the brain. Objectives: this work aimed to evaluate the appearance of P 300 wave in response to relevant visual stimuli and its absence to irrelevant ones and to evaluate the latency and amplitude of P300 wave in response to well-known persons and places. Methods This is a cross sectional prospective study carried out on 225 normal individuals at Clinical Neurophysiology Unit, Faculty of Medicine, Cairo University. It comprised both sexes aged from 18 to 70 years old; participants were divided into 3 groups. An endogenous ERP;P300 wave was seen evoked in response to rare, presented, recognized, meaningful stimulus, the peak amplitude was calculated and peak latency was measured from the time of stimulus onset. Results A photo of a person or place known to the test subject elicited a well-marked P300 response, while that of an unknown personality or place didn’t generate noticeable response. P300 wave latency and amplitude was recorded. There was a significant association between P300 amplitude and latency with age and educational level. Conclusion P300 wave is valuable in detecting concealed knowledge stored in the participant’s brain and is an objective and reliable test.

B-18. Where ‘ERP’ is and where it is going?

Sutton (1965) classified Event-Related Potentials (ERPs) into exogenous and endogenous components. Exogenous ERPs would reflect automatic processing and endogenous ones would reflect controlled processing (Picton and Hillyard, 1988). Only mismatch negativity (MMN), an automatic but endogenous ERP found by Naatanen et al. (1978), does not match this classification. MMN is automatically elicited by occasional deviation in a sequence of homogenous sounds. MMN is considered to be generated by the comparison process between deviated sound and neural trace of preceding sounds encoded in sensory memory. Plenty of studies have given evidence for “memory trace theory”. MMN provides a promising tool for clinical populations, because MMN elicitation does not require any tasks and MMN to duration deviation (i.e., duration-MMN) is exceptionally sensitive to clinical populations such as schizophrenia. Michie et al. (2000) reported that only duration-MMN was reliably reduced in patients with schizophrenia. Todd et al. (2007) also reported that a definite reduction in early schizophrenia was evident in duration-MMN but not frequency deviants. Impairment of MMN is one of the most robust findings in schizophrenia. MMN to duration is a candidate of the trait marker. Importantly, MNN reduction predict conversion to psychosis among the subjects clinically at risk-mental state (ARMS).

P300 brainwave extraction from EEG signals: An unsupervised approach

The P300 is an endogenous event-related potential (ERP) that is naturally elicited by rare and significant stimuli, arisen from the frontal, temporal and occipital lobe of the brain, although is usually measured in the parietal lobe. P300 signals are increasingly used in brain-computer interfaces (BCI) because the users of ERP-based BCIs need no special training. In order to detect the P300 signal, most studies in the field have been focused on a supervised approach, dealing with over-fitting filters and the need for later validation. In this paper we start bridging this gap by modeling an unsupervised classifier of the P300 presence based on a weighted score. This is carried out through the use of matched filters that weight events that are likely to represent the P300 wave. The optimal weights are determined through a study of the data’s features. The combination of different artifact cancelation methods and the P300 extraction techniques provides a marked, statistically significant, improvement in accuracy at the level of the top-performing algorithms for a supervised approach presented in the literature to date. This innovation brings a notable impact in ERP-based communicators, appointing to the development of a faster and more reliable BCI technology.

Cognitive event-related potentials in multiple sclerosis: Correlation with MRI and neuropsychological findings

BackgroundCognitive event-related potentials (ERPs) have been previously correlated with T2 lesion load (Τ2LL) in patients with multiple sclerosis (MS). It is currently unknown, however, whether ERPs also correlate with brain atrophy or the presence of T1 hypointense lesions (“black holes”) which reflect tissue destruction and axonal loss. The primary aim of the current study is to explore the effect of neuroradiological parameters such as brain atrophy, T1 and T2 lesion load on auditory ERPs in MS patients. In addition, we correlated cognitive impairment with neurophysiological (ERP) and neuroradiological (MRI) variables and investigated whether a combination of ERP and MRI parameters is capable of distinguishing patients suffering from secondary progressive (SP), primary progressive (PP) and relapsing-remitting (RR) MS. Materials and methodsThe study sample consisted of fifty nine MS patients (mean age±SD: 37.82±1.38 years; average disease duration: 6.76±5.3 years) and twenty six age-matched controls (mean age±SD: 41.42±15.39 years). The patients’ EDSS and NRS scores were 3.77±2.14 (range: 1–7.5) and 75.88±11.99 (range: 42–94) respectively. ERPs were recorded using the auditory “odd-ball” paradigm. T1 and T2 lesions were automatically segmented using an edge-finding tool and total lesion volumes were calculated. MRI measures of brain atrophy included third ventricle width (THIRDVW) and the ratio of mid-sagittal corpus callosum area to the mid-sagittal intracranial skull surface area (CC/MISS). Statistical analysis was performed using multiple regression, principal component (PCA) and discriminant analysis. ResultsT1 lesion load emerged as the most significant predictor of P300 and N200 latency. The rest of the endogenous ERPs parameters (P300 amplitude, N200 amplitude) were not significantly correlated with the MRI variables. PCA of pooled neuroradiological and neurophysiological markers suggested that four components accounted for 64.6% of the total variability. Discriminant analysis based on ERP & MRI markers classified correctly 79.63% of patients in RR, PP and SP subgroups. ConclusionT1 lesion load is the most significant MRI correlate of auditory ERPs in MS patients. Importantly, ERPs in combination with MRI variables can be usefully employed for distinguishing patients with different subtypes of MS.

Reconstructing ERP amplitude effects after compensating for trial-to-trial latency jitter: A solution based on a novel application of residue iteration decomposition

Stimulus-locked averaged event-related potentials (ERPs) are among the most frequently used signals in Cognitive Neuroscience. However, the late, cognitive or endogenous ERP components are often variable in latency from trial to trial in a component-specific way, compromising the stability assumption underlying the averaging scheme. Here we show that trial-to-trial latency variability of ERP components not only blurs the average ERP waveforms, but may also attenuate existing or artificially induce condition effects in amplitude. Hitherto this problem has not been well investigated. To tackle this problem, a method to measure and compensate component-specific trial-to-trial latency variability is required. Here we first systematically analyze the problem of single trial latency variability for condition effects based on simulation. Then, we introduce a solution by applying residue iteration decomposition (RIDE) to experimental data. RIDE separates different clusters of ERP components according to their time-locking to stimulus onsets, response times, or neither, based on an algorithm of iterative subtraction. We suggest to reconstruct ERPs by re-aligning the component clusters to their most probable single trial latencies. We demonstrate that RIDE-reconstructed ERPs may recover amplitude effects that are diminished or exaggerated in conventional averages by trial-to-trial latency jitter. Hence, RIDE-corrected ERPs may be a valuable tool in conditions where ERP effects may be compromised by latency variability.

Endogenous event-related potentials in patients with primary Sjögren’s syndrome without central nervous system involvement

Objectives: Endogenous cognitive event-related potentials (CERPs) reflect higher-level processing of sensory information and can be used to evaluate cognitive functions. The aim of this paper was to determine whether there are any abnormalities in the electrophysiological parameters of CERPs in patients with primary Sjögren’s syndrome (pSS) but without symptoms of central nervous system (CNS) involvement or mental disorder. The analysis of CERP parameters was then correlated with the clinical status of the patients and with some of the immunological parameters in the patient group.Method: Thirty consecutive patients with pSS (29 females, one male) were included in the study. All the patients underwent CERP examination.Results: There was a significant prolongation of the latency of P300 and N200 potentials in patients with pSS. Abnormalities in electrophysiological parameters of CERPs correlated with the duration of the disease, salivary gland abnormalities, and elevated erythrocyte sedimentation rate (ESR) values. Patients with coexisting chronic fatigue syndrome (CFS) had larger P300 amplitudes. There were no statistically significant changes in the electrophysiological parameters of CERPs in patients with pSS dependent on the presence of peripheral nervous system (PNS) lesions, skin changes, arthritis, abnormalities in white blood cells and the immune system or the levels of blood lipids.Conclusions: The results of the study suggest the presence of a minor cognitive dysfunction in patients with pSS without symptoms of CNS involvement or mental disorder. Cognitive dysfunction correlated with the disease duration time and the severity of inflammatory changes (salivary gland abnormalities and inflammatory markers in the blood). Further and larger longitudinal studies are necessary for confirmation of this correlation.

Abnormal Centroparietal ERP Response in Predominantly Medication-Naive Adolescent Boys With ADHD During Both Response Inhibition and Execution

Abnormal event-related potential (ERP) responses have been reported in children and adolescents with attention deficit hyperactivity disorder (ADHD) and a medication history compared with in healthy controls during tasks of response control and conflict inhibition. This study reports neurophysiologic correlates of a task dependent on these cognitive functions in a large, predominantly medication naive, group of adolescents with ADHD compared with that in healthy age- and intelligence quotient (IQ)-matched controls using area-under-the-curve (AUC) analysis. Fifty-four adolescents with ADHD and 55 healthy comparisons completed a hybrid conflict and response inhibition Go/NoGo ERP task. The performance data showed that children with ADHD compared with controls had deficits in both the inhibitory measures (higher commission errors) and the Go process of the task (slower reaction times and enhanced omission errors). The ERP data showed significant impairments in brain function in the ADHD relative to the control group for late, endogenous ERPs (N2, P3a, and P3b), whereas no group differences were found for the earlier P200. All findings remained when a minority of children with medication history was excluded. Furthermore, deficits were not specific to the inhibitory processes of the task but were equally observed during the execution functions. Group differences were particularly pronounced over central and centroparietal sites across all time points, presumably reflecting the midline attention system mediated by anterior and posterior cingulate that is important for generic, condition-independent visual-spatial attention and response selection processes. The findings demonstrate that adolescents with ADHD have abnormal ERP responses not only during inhibitory, but also execution-related processes and, furthermore, that these deficits are independent from medication history.

Auditory Event-related Potentials in Children With Attention Deficit Hyperactivity Disorder

Recording of event-related potentials (ERPs) from the scalp is a noninvasive technique reflecting the sensory and cognitive processes associated with attention tasks. Attention deficit hyperactivity disorder (ADHD) is a disorder involving deficits in attention and behavioral control. The aim of this study was to investigate the difference in ERPs between normal children and those with ADHD. We examined 50 children with ADHD and 51 age-matched controls. All children with ADHD met the full criteria for ADHD according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). The auditory oddball paradigm was applied, and event-related long-latency components (N1, P2, N2 and P3) from Fz, Cz and Pz were measured in each test subject. Children with ADHD showed a significantly longer latency and a lower amplitude of P3 compared to normal control children (p < 0.01). Delayed N2 latency at the Pz electrode was shown in children with ADHD compared to normal controls (p < 0.01). No differences in other ERP indices were found between children with ADHD and controls. When divided into four age groups, the latency of P3 was significantly increased in all age groups and a significantly smaller amplitude in P3 over the central region was found in children with ADHD > 10 years of age (p < 0.05). We found that the endogenous ERPs (P3 and N2) were significantly affected in children with ADHD, compared to exogenous ERPs (N1 and P2). Increased latency of P3 suggests a slower processing speed, and decreased P3 amplitude is interpreted as disruption of inhibitory control in children with ADHD. These results indicate a neurocognitive abnormality in ADHD, as presented by a reduction in ERP response.

Event-related potentials and changes of brain rhythm oscillations during working memory activation in patients with first-episode psychosis

Earlier contributions have documented significant changes in sensory, attention-related endogenous event-related potential (ERP) components and θ band oscillatory responses during working memory activation in patients with schizophrenia. In patients with first-episode psychosis, such studies are still scarce and mostly focused on auditory sensory processing. The present study aimed to explore whether subtle deficits of cortical activation are present in these patients before the decline of working memory performance. We assessed exogenous and endogenous ERPs and frontal θ event-related synchronization (ERS) in patients with first-episode psychosis and healthy controls who successfully performed an adapted 2-back working memory task, including 2 visual n-backworking memory tasks as well as oddball detection and passive fixation tasks. We included 15 patients with first-episode psychosis and 18 controls in this study. Compared with controls, patients with first-episode psychosis displayed increased latencies of early visual ERPs and phasic θ ERS culmination peak in all conditions. However, they also showed a rapid recruitment of working memory-related neural generators, even in pure attention tasks, as indicated by the decreased N200 latency and increased amplitude of sustained θ ERS in detection compared with controls. Owing to the limited sample size, no distinction was made between patients with first-episode psychosis with positive and negative symptoms. Although we controlled for the global load of neuroleptics, medication effect cannot be totally ruled out. The present findings support the concept of a blunted electroencephalographic response in patients with first-episode psychosis who recruit the maximum neural generators in simple attention conditions without being able to modulate their brain activation with increased complexity of working memory tasks.

Documenting, modelling and exploiting P300 amplitude changes due to variable target delays in Donchin's speller

The P300 is an endogenous event-related potential (ERP) that is naturally elicited by rare and significant external stimuli. P300s are used increasingly frequently in brain–computer interfaces (BCIs) because the users of ERP-based BCIs need no special training. However, P300 waves are hard to detect and, therefore, multiple target stimulus presentations are needed before an interface can make a reliable decision. While significant improvements have been made in the detection of P300s, no particular attention has been paid to the variability in shape and timing of P300 waves in BCIs. In this paper we start filling this gap by documenting, modelling and exploiting a modulation in the amplitude of P300s related to the number of non-targets preceding a target in a Donchin speller. The basic idea in our approach is to use an appropriately weighted average of the responses produced by a classifier during multiple stimulus presentations, instead of the traditional plain average. This makes it possible to weigh more heavily events that are likely to be more informative, thereby increasing the accuracy of classification. The optimal weights are determined through a mathematical model that precisely estimates the accuracy of our speller as well as the expected performance improvement w.r.t. the traditional approach. Tests with two independent datasets show that our approach provides a marked statistically significant improvement in accuracy over the top-performing algorithm presented in the literature to date. The method and the theoretical models we propose are general and can easily be used in other P300-based BCIs with minimal changes.

Time-of-day-dependent Effects of Monochromatic Light Exposure on Human Cognitive Function

Light elicits non-visual effects on a wide range of biological functions and behavior. These effects are mediated by a melanopsin-based photoreceptor system that is very sensitive to blue light (440-480 nm) relative to the three-cone visual photopic system. The aim of the current study was to assess the time-of-day-dependent effects of two different wavelength monochromatic lights at 458 nm and 550 nm on human cognitive function. We conducted an experiment in the daytime and nighttime on different days. Twelve subjects were selected, none of whom was either morning-type or evening-type, as assessed by a translated version of the morningness/eveningness questionnaire. The cognitive function was measured by event-related potential (ERP) using an oddball task, and arousal level was measured by the Alpha Attenuation Test (AAT). We found that 458 nm light exposure caused a significantly larger P300 amplitude than occurred with 550 nm light. There was a significant interaction among wavelength, time of day, and electrode site. Exposure to 458 nm light induced a larger P300 amplitude at nighttime than in the daytime at the Fz electrode site. The Alpha Attenuation Coefficient (AAC) at nighttime was higher than in the daytime. Our results suggest that short wavelength monochromatic light can affect the circadian rhythms of cognitive functions, and indicate that these effects are mediated by a melanopsin-based photoreceptor system. This study has extended previous findings in terms of time of day, and higher cognitive function by using an endogenous ERP component, P300.

Evoked activity and EEG phase resetting in the genesis of auditory Go/NoGo ERPs

Current views of the genesis of the event-related potential (ERP) contrast the phase-reset and evoked activity models. In the former, a portion of the ongoing electroencephalographic (EEG) activity becomes phase-locked at stimulus onset; in the latter, processing in the brain contributes additional time-locked activity at each trial. This study aimed to explore these perspectives in an auditory Go/NoGo task. The interactions between these processes were examined using the amplitudes and topographies of pre- and post-stimulus EEGs in traditional bands, and the averaged ERPs, together with time-frequency analysis. Results indicate that both evoked activity and phase locking of ongoing EEG activity contribute substantially to the different Go and NoGo ERP components. Phase locking contributes most strongly to the early exogenous ERP components, with evoked brain activity related to cognitive processing contributing strongly to the endogenous ERP components. Evidence also suggests that extensive phase realignments may generate the power increases associated with early exogenous components. It is concluded that exogenous ERP components arise substantially from phase-resetting mechanisms involving ongoing EEG activity. In contrast, the endogenous components are substantially produced by evoked activity in various frequency bands, and their differences reflect differential cortical processing required for appropriate responding to the Go vs. NoGo stimuli.

Predicting cognitive decline in Mild Cognitive Impairment

Recent studies described several changes of endogenous event related potentials (ERP) and brain rhythm synchronization during memory activation in patients with Alzheimer's disease (AD). To examine whether memoryrelated EEG parameters may predict cognitive decline in mild cognitive impairment (MCI), we assessed P200 and N200 latencies as well as beta event-related synchronization (ERS) in 16 elderly controls (EC), 29 MCI cases and 10 patients with AD during the successful performance of a pure attentional detection task as compared to a highly working memory demanding 2-back task. At one year follow-up, sixteen MCI patients showed progressive cognitive decline (PMCI) and thirteen remained stable (SMCI). Both P200 and N200 latencies in the 2-back task were longer in PMCI and AD cases compared to EC and SMCI cases. During the interval 1000 ms to 1700 ms after stimulus, beta ERS at parietal electrodes was of lower amplitude in PMCI and AD compared to EC and SMCI cases. Univariate models showed that P200, N200 and log% beta values were significantly related to the SMCI/PMCI distinction with areas under the receiver operating characteristic curve of 0.93, 0.78 and 0.72, respectively. The combination of all three EEG hallmarks was the stronger predictor of MCI deterioration with 90% of correctly classified MCI cases. Our data reveal that PMCI and clinically overt AD share the same pattern of working memoryrelated EEG activation characterized by increased P200N200 latencies and decreased beta ERS. They also show that P200 latency during the 2-back task may be a simple and promising EEG marker of rapid cognitive decline in MCI. from International Society on Brain and Behaviour: 3rd International Congress on Brain and Behaviour Thessaloniki, Greece. 28 November – 2 December 2007

P3a and P3b components associated to the neurocognitive evaluation of invalidly cued targets

The present report focuses on evaluating the neurocognitive consequences of the correct or incorrect spatial prediction induced by a spatial cue. Positions in the vertical meridian were cued in order to evaluate the cognitive consequences in the processing of the validly (VC) or invalidly cued (IC) targets. The behavioural responses and the 64 EEG channel were recorded. The late endogenous event-related potential (ERP) induced by target stimuli in VC and IC targets were compared in voltage amplitude, voltage and current source density topographies. The P3a and a late positive complex, possibly P3b were increased in a statistically significant manner in the IC targets with regard to the VC targets. The previous result suggests that subjects prepare to accomplish the task upon specification of the cue, and when the IC target appeared it is treated as a low probability stimulus in a similar manner to deviant stimuli in odd-ball paradigms.

Working memory load–related electroencephalographic parameters can differentiate progressive from stable mild cognitive impairment

Recent studies described several changes of endogenous event-related potentials (ERP) and brain rhythm synchronization during memory activation in patients with Alzheimer’s disease (AD). To examine whether memory-related EEG parameters may predict cognitive decline in mild cognitive impairment (MCI), we assessed P200 and N200 latencies as well as beta event-related synchronization (ERS) in 16 elderly controls (EC), 29 MCI cases and 10 patients with AD during the successful performance of a pure attentional detection task as compared with a highly working memory demanding two-back task. At 1 year follow-up, 16 MCI patients showed progressive cognitive decline (PMCI) and 13 remained stable (SMCI). Both P200 and N200 latencies in the two-back task were longer in PMCI and AD cases compared with EC and SMCI cases. During the interval 1000 ms to 1700 ms after stimulus, beta ERS at parietal electrodes was of lower amplitude in PMCI and AD compared with EC and SMCI cases. Univariate models showed that P200, N200 and log% beta values were significantly related to the SMCI/PMCI distinction with areas under the receiver operating characteristic curve of 0.93, 0.78 and 0.72, respectively. The combination of all three EEG hallmarks was the stronger predictor of MCI deterioration with 90% of correctly classified MCI cases. Our data reveal that PMCI and clinically overt AD share the same pattern of working memory-related EEG activation characterized by increased P200–N200 latencies and decreased beta ERS. They also show that P200 latency during the two-back task may be a simple and promising EEG marker of rapid cognitive decline in MCI.