P300 (neuroscience)

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P300 latency and amplitude trajectories across the lifespan as obtained from the cross-sectional dataset. Dots represent scores from individual participants. From From P300 Development across the Lifespan: A Systematic Review and Meta-Analysis. The latency and amplitude of the P300 response may vary as a function of age. P300 latency and amplitude trajectories across the lifespan as obtained from the cross-sectional dataset.png
P300 latency and amplitude trajectories across the lifespan as obtained from the cross-sectional dataset. Dots represent scores from individual participants. From From P300 Development across the Lifespan: A Systematic Review and Meta-Analysis. The latency and amplitude of the P300 response may vary as a function of age.
The P300 response of different healthy subjects in a two-tone auditory oddball paradigm. The plots show the average response to oddball (red) and standard (blue) trials and their difference (black). From Surprise response as a probe for compressed memory states. These examples show the significant individual variability in amplitude, latency and waveform shape across different subjects. P300 response of different subjects.png
The P300 response of different healthy subjects in a two-tone auditory oddball paradigm. The plots show the average response to oddball (red) and standard (blue) trials and their difference (black). From Surprise response as a probe for compressed memory states. These examples show the significant individual variability in amplitude, latency and waveform shape across different subjects.

The P300 (P3) wave is an event-related potential (ERP) component elicited in the process of decision making. It is considered to be an endogenous potential, as its occurrence links not to the physical attributes of a stimulus, but to a person's reaction to it. More specifically, the P300 is thought to reflect processes involved in stimulus evaluation or categorization.

Contents

It is usually elicited using the oddball paradigm, in which low-probability target items are mixed with high-probability non-target (or "standard") items. When recorded by electroencephalography (EEG), it surfaces as a positive deflection in voltage with a latency (delay between stimulus and response) of roughly 250 to 500 ms. [3] In the scientific literature a differentiation is often made in the P3, which is divided according to time: Early P3 window (300-400 ms) and Late P3 window (380-440 ms). [4]

The signal is typically measured most strongly by the electrodes covering the parietal lobe. The presence, magnitude, topography and timing of this signal are often used as metrics of cognitive function in decision-making processes. While the neural substrates of this ERP component still remain hazy, the reproducibility and ubiquity of this signal makes it a common choice for psychological tests in both the clinic and laboratory.

History

Early observations of the P300 (more specifically, the component that would later be named the P3b) were reported in the mid-1960s. In 1964, researchers Chapman and Bragdon [5] found that ERP responses to visual stimuli differed depending on whether the stimuli had meaning or not. They showed subjects two kinds of visual stimuli: numbers and flashes of light. Subjects viewed these stimuli one at a time in a sequence. For every two numbers, the subjects were required to make simple decisions, such as telling which of the two numbers was numerically smaller or larger, which came first or second in the sequence, or whether they were equal. When examining evoked potentials to these stimuli (i.e., ERPs), Chapman and Bragdon found that both the numbers and the flashes elicited the expected sensory responses (e.g., visual N1 components), and that the amplitude of these responses varied in an expected fashion with the intensity of the stimuli. They also found that the ERP responses to the numbers, but not to the light flashes, contained a large positivity that peaked around 300 ms after the stimulus appeared. Chapman and Bragdon speculated that this differential response to the numbers, which came to be known as the P300 response, resulted from the fact that the numbers were meaningful to the participants, based on the task that they were asked to perform.

In 1965, Sutton and colleagues published results from two experiments that further explored this late positivity. They presented subjects with either a cue that indicated whether the following stimulus would be a click or a flash, or a cue which required subjects to guess whether the following stimulus would be a click or a flash. They found that when subjects were required to guess what the following stimulus would be, the amplitude of the "late positive complex" [6] was larger than when they knew what the stimulus would be. In a second experiment, they presented two cue types. For one cue there was a 2 in 3 chance that the following stimulus would be a click and a 1 in 3 chance that the following stimulus would be a flash. The second cue type had probabilities that were the reverse of the first. They found that the amplitude of the positive complex was larger in response to the less probable stimuli, or the one that only had a 1 in 3 chance of appearing. Another important finding from these studies is that this late positive complex was observed for both the clicks and flashes, indicating that the physical type of the stimulus (auditory or visual) did not matter.

In later studies published in 1967, Sutton and colleagues had subjects guess whether they would hear one click or two clicks. [7] They again observed a positivity around 300 ms after the second click occurred – or would have occurred, in the case of the single click. They also had subjects guess how long the interval between clicks might be, and in this case, the late positivity occurred 300 ms after the second click. This shows two important findings: first, that this late positivity occurred when uncertainty about the type of click was resolved, and second, that even an absence of a stimulus would elicit the late positive complex, if said stimulus was relevant to the task. These early studies encouraged the use of ERP methods to study cognition and provided a foundation for the extensive work on the P300 in the decades that followed.

P3a and P3b

The P300 response as a function of the oddball probability. From Surprise response as a probe for compressed memory states. The ERP shows a larger P300 response magnitude to oddball stimuli and a lower P300 response to standard stimuli as the oddball probability decreases. P300 vs oddballProbability.svg
The P300 response as a function of the oddball probability. From Surprise response as a probe for compressed memory states. The ERP shows a larger P300 response magnitude to oddball stimuli and a lower P300 response to standard stimuli as the oddball probability decreases.

The P3a, or novelty P3, [8] has a positive-going amplitude that displays maximum amplitude over frontal/central electrode sites and has a peak latency in the range of 250–280 ms. The P3a has been associated with brain activity related to the engagement of attention (especially the orienting, involuntary shifts to changes in the environment), and the processing of novelty. [9]

The P3b has a positive-going amplitude (usually relative to a reference behind the ear or the average of two such references) that peaks at around 300 ms, and the peak will vary in latency from 250 to 500 ms or more, depending upon the task and the individual subject response. [3] Amplitudes are typically highest on the scalp over parietal brain areas. [3] The P3b has been a prominent tool used to study cognitive processes, especially psychology research on information processing. Generally speaking, improbable events will elicit a P3b, and the less probable the event, the larger the P3b amplitude. [10] This was shown to be true both for the overall probability and for the local probability. [2] However, in order to elicit a P3b, the improbable event must be related to the task at hand in some way (for example, the improbable event could be an infrequent target letter in a stream of letters, to which a subject might respond with a button press). The P3b can also be used to measure how demanding a task is on cognitive workload. [10]

Since the initial discovery of the P300, research has shown that the P300 has two subcomponents. The subcomponents are the novelty P3, or P3a, and the classic P300, which has since been renamed P3b. [11]

Applications

Since the mid-1980s, one of the most discussed uses of ERPs such as the P300 is related to lie detection. In a proposed "guilty knowledge test" [12] a subject is interrogated via the oddball paradigm much as they would be in a typical lie-detector situation. This practice has recently enjoyed increased legal permissibility while conventional polygraphy has seen its use diminish, in part owing to the unconscious and uncontrollable aspects of the P300. The technique relies on reproducible elicitation of the P300 wave, central to the idea of a Memory and Encoding Related Multifaceted Electroencephalographic Response (MERMER) developed by Dr. Lawrence Farwell.

Applications in brain-computer interfacing (BCI) have also been proposed. [13] [14] [15] The P300 has a number of desirable qualities that aid in implementation of such systems. First, the waveform is consistently detectable and is elicited in response to precise stimuli. The P300 waveform can also be evoked in nearly all subjects with little variation in measurement techniques, which may help simplify interface designs and permit greater usability. The speed at which an interface is able to operate depends on how detectable the signal is despite "noise." One negative characteristic of the P300 is that the amplitude of the waveform requires averaging of multiple recordings to isolate the signal. This and other post-recording processing steps determine the overall speed of an interface. [14] The algorithm proposed by Farwell and Donchin [16] provides an example of a simple BCI that relies on the unconscious decision making processes of the P300 to drive a computer. A 6×6 grid of characters is presented to the subject, and various columns or rows are highlighted. When a column or row contains the character a subject desires to communicate, the P300 response is elicited (since this character is "special" it is the target stimulus described in the typical oddball paradigm). The combination of the row and column which evoked the response locates the desired character. A number of such trials must be averaged to clear noise from the EEG. The speed of the highlighting determines the number of characters processed per minute. Results from studies using this setup show that normal subjects could achieve a 95% success rate at 3.4–4.3 chars/min. Such success rates are not limited to non-disabled users; a study conducted in 2000 revealed that 4 paralyzed participants (one with complete paraplegia, three with incomplete paraplegia) performed as successfully as 10 normal participants. [14]

Scientific research often relies on measurement of the P300 to examine event related potentials, especially with regard to decision making. Because cognitive impairment is often correlated with modifications in the P300, the waveform can be used as a measure for the efficacy of various treatments on cognitive function. Some have suggested its use as a clinical marker for precisely these reasons. There is a broad range of uses for the P300 in clinical research. [17]

Some research groups have performed fMRI combined to EEG in order to achieve inner-speech dictation and the approach of inner-speech recognition. [18] [19] [20]

The P300 wave obtained by visual stimulation is used to assess cognitive processes in humans, and the value of the latency and amplitude of the P300 wave can be a measure of the severity of dementia processes. [21] The analysis of P300 wave latency seems to be particularly useful in the diagnosis of mild cognitive impairment (MCI). [22]

See also

Related Research Articles

An evoked potential or evoked response is an electrical potential in a specific pattern recorded from a specific part of the nervous system, especially the brain, of a human or other animals following presentation of a stimulus such as a light flash or a pure tone. Different types of potentials result from stimuli of different modalities and types. Evoked potential is distinct from spontaneous potentials as detected by electroencephalography (EEG), electromyography (EMG), or other electrophysiologic recording method. Such potentials are useful for electrodiagnosis and monitoring that include detections of disease and drug-related sensory dysfunction and intraoperative monitoring of sensory pathway integrity.

<span class="mw-page-title-main">Event-related potential</span> Brain response that is the direct result of a specific sensory, cognitive, or motor event

An event-related potential (ERP) is the measured brain response that is the direct result of a specific sensory, cognitive, or motor event. More formally, it is any stereotyped electrophysiological response to a stimulus. The study of the brain in this way provides a noninvasive means of evaluating brain functioning.

The orienting response (OR), also called orienting reflex, is an organism's immediate response to a change in its environment, when that change is not sudden enough to elicit the startle reflex. The phenomenon was first described by Russian physiologist Ivan Sechenov in his 1863 book Reflexes of the Brain, and the term was coined by Ivan Pavlov, who also referred to it as the Shto takoye? reflex. The orienting response is a reaction to novel or significant stimuli. In the 1950s the orienting response was studied systematically by the Russian scientist Evgeny Sokolov, who documented the phenomenon called "habituation", referring to a gradual "familiarity effect" and reduction of the orienting response with repeated stimulus presentations.

The N400 is a component of time-locked EEG signals known as event-related potentials (ERP). It is a negative-going deflection that peaks around 400 milliseconds post-stimulus onset, although it can extend from 250-500 ms, and is typically maximal over centro-parietal electrode sites. The N400 is part of the normal brain response to words and other meaningful stimuli, including visual and auditory words, sign language signs, pictures, faces, environmental sounds, and smells.

The mismatch negativity (MMN) or mismatch field (MMF) is a component of the event-related potential (ERP) to an odd stimulus in a sequence of stimuli. It arises from electrical activity in the brain and is studied within the field of cognitive neuroscience and psychology. It can occur in any sensory system, but has most frequently been studied for hearing and for vision, in which case it is abbreviated to vMMN. The (v)MMN occurs after an infrequent change in a repetitive sequence of stimuli For example, a rare deviant (d) stimulus can be interspersed among a series of frequent standard (s) stimuli. In hearing, a deviant sound can differ from the standards in one or more perceptual features such as pitch, duration, loudness, or location. The MMN can be elicited regardless of whether someone is paying attention to the sequence. During auditory sequences, a person can be reading or watching a silent subtitled movie, yet still show a clear MMN. In the case of visual stimuli, the MMN occurs after an infrequent change in a repetitive sequence of images.

The contingent negative variation (CNV) is a negative slow surface potential, as measured by electroencephalography (EEG), that occurs during the period between a warning stimulus or signal and an imperative ("go") stimulus. The CNV was one of the first event-related potential (ERP) components to be described. The CNV component was first described by W. Grey Walter and colleagues in an article published in Nature in 1964. The importance of this finding was that it was one of the first studies which showed that consistent patterns of the amplitude of electric responses could be obtained from the large background noise which occurs in EEG recordings and that this activity could be related to a cognitive process such as expectancy.

The P600 is an event-related potential (ERP) component, or peak in electrical brain activity measured by electroencephalography (EEG). It is a language-relevant ERP component and is thought to be elicited by hearing or reading grammatical errors and other syntactic anomalies. Therefore, it is a common topic of study in neurolinguistic experiments investigating sentence processing in the human brain.

The early left anterior negativity is an event-related potential in electroencephalography (EEG), or component of brain activity that occurs in response to a certain kind of stimulus. It is characterized by a negative-going wave that peaks around 200 milliseconds or less after the onset of a stimulus, and most often occurs in response to linguistic stimuli that violate word-category or phrase structure rules. As such, it is frequently a topic of study in neurolinguistics experiments, specifically in areas such as sentence processing. While it is frequently used in language research, there is no evidence yet that it is necessarily a language-specific phenomenon.

In neuroscience, the N100 or N1 is a large, negative-going evoked potential measured by electroencephalography ; it peaks in adults between 80 and 120 milliseconds after the onset of a stimulus, and is distributed mostly over the fronto-central region of the scalp. It is elicited by any unpredictable stimulus in the absence of task demands. It is often referred to with the following P200 evoked potential as the "N100-P200" or "N1-P2" complex. While most research focuses on auditory stimuli, the N100 also occurs for visual, olfactory, heat, pain, balance, respiration blocking, and somatosensory stimuli.

Difference due to memory (Dm) indexes differences in neural activity during the study phase of an experiment for items that subsequently are remembered compared to items that are later forgotten. It is mainly discussed as an event-related potential (ERP) effect that appears in studies employing a subsequent memory paradigm, in which ERPs are recorded when a participant is studying a list of materials and trials are sorted as a function of whether they go on to be remembered or not in the test phase. For meaningful study material, such as words or line drawings, items that are subsequently remembered typically elicit a more positive waveform during the study phase. This difference typically occurs in the range of 400–800 milliseconds (ms) and is generally greatest over centro-parietal recording sites, although these characteristics are modulated by many factors.

The P3a, or novelty P3, is a component of time-locked (EEG) signals known as event-related potentials (ERP). The P3a is a positive-going scalp-recorded brain potential that has a maximum amplitude over frontal/central electrode sites with a peak latency falling in the range of 250–280 ms. The P3a has been associated with brain activity related to the engagement of attention and the processing of novelty.

In neuroscience, the visual P200 or P2 is a waveform component or feature of the event-related potential (ERP) measured at the human scalp. Like other potential changes measurable from the scalp, this effect is believed to reflect the post-synaptic activity of a specific neural process. The P2 component, also known as the P200, is so named because it is a positive going electrical potential that peaks at about 200 milliseconds after the onset of some external stimulus. This component is often distributed around the centro-frontal and the parieto-occipital areas of the scalp. It is generally found to be maximal around the vertex of the scalp, however there have been some topographical differences noted in ERP studies of the P2 in different experimental conditions.

The N200, or N2, is an event-related potential (ERP) component. An ERP can be monitored using a non-invasive electroencephalography (EEG) cap that is fitted over the scalp on human subjects. An EEG cap allows researchers and clinicians to monitor the minute electrical activity that reaches the surface of the scalp from post-synaptic potentials in neurons, which fluctuate in relation to cognitive processing. EEG provides millisecond-level temporal resolution and is therefore known as one of the most direct measures of covert mental operations in the brain. The N200 in particular is a negative-going wave that peaks 200-350ms post-stimulus and is found primarily over anterior scalp sites. Past research focused on the N200 as a mismatch detector, but it has also been found to reflect executive cognitive control functions, and has recently been used in the study of language.

Error-related negativity (ERN), sometimes referred to as the Ne, is a component of an event-related potential (ERP). ERPs are electrical activity in the brain as measured through electroencephalography (EEG) and time-locked to an external event or a response. A robust ERN component is observed after errors are committed during various choice tasks, even when the participant is not explicitly aware of making the error; however, in the case of unconscious errors the ERN is reduced. An ERN is also observed when non-human primates commit errors.

Somatosensory evoked potential is the electrical activity of the brain that results from the stimulation of touch. SEP tests measure that activity and are a useful, noninvasive means of assessing somatosensory system functioning. By combining SEP recordings at different levels of the somatosensory pathways, it is possible to assess the transmission of the afferent volley from the periphery up to the cortex. SEP components include a series of positive and negative deflections that can be elicited by virtually any sensory stimuli. For example, SEPs can be obtained in response to a brief mechanical impact on the fingertip or to air puffs. However, SEPs are most commonly elicited by bipolar transcutaneous electrical stimulation applied on the skin over the trajectory of peripheral nerves of the upper limb or lower limb, and then recorded from the scalp. In general, somatosensory stimuli evoke early cortical components, generated in the contralateral primary somatosensory cortex (S1), related to the processing of the physical stimulus attributes. About 100 ms after stimulus application, additional cortical regions are activated, such as the secondary somatosensory cortex (S2), and the posterior parietal and frontal cortices, marked by a parietal P100 and bilateral frontal N140. SEPs are routinely used in neurology today to confirm and localize sensory abnormalities, to identify silent lesions and to monitor changes during surgical procedures.

The late positive component or late positive complex (LPC) is a positive-going event-related brain potential (ERP) component that has been important in studies of explicit recognition memory. It is generally found to be largest over parietal scalp sites, beginning around 400–500 ms after the onset of a stimulus and lasting for a few hundred milliseconds. It is an important part of the ERP "old/new" effect, which may also include modulations of an earlier component similar to an N400. Similar positivities have sometimes been referred to as the P3b, P300, and P600. Here, we use the term "LPC" in reference to this late positive component.

<span class="mw-page-title-main">P3b</span>

The P3b is a subcomponent of the P300, an event-related potential (ERP) component that can be observed in human scalp recordings of brain electrical activity. The P3b is a positive-going amplitude peaking at around 300 ms, though the peak will vary in latency from 250 to 500 ms or later depending upon the task and on the individual subject response. Amplitudes are typically highest on the scalp over parietal brain areas.

The N170 is a component of the event-related potential (ERP) that reflects the neural processing of faces, familiar objects or words. Furthermore, the N170 is modulated by prediction error processes.

N2pc refers to an ERP component linked to selective attention. The N2pc appears over visual cortex contralateral to the location in space to which subjects are attending; if subjects pay attention to the left side of the visual field, the N2pc appears in the right hemisphere of the brain, and vice versa. This characteristic makes it a useful tool for directly measuring the general direction of a person's attention with fine-grained temporal resolution.

The oddball paradigm is an experimental design used within psychology research. Presentations of sequences of repetitive stimuli are infrequently interrupted by a deviant stimulus. The reaction of the participant to this "oddball" stimulus is recorded.

References

  1. ↑ Rik van Dinteren; Martijn Arns; Marijtje L. A. Jongsma; Roy P. C. Kessels (2014). "P300 Development across the Lifespan: A Systematic Review and Meta-Analysis". PLOS ONE. 9 (2): e87347. doi: 10.1371/journal.pone.0087347 . PMC   3923761 . PMID   24551055.
  2. 1 2 3 Levi-Aharoni, Hadar; Shriki, Oren; Tishby, Naftali (2020-02-03). "Surprise response as a probe for compressed memory states". PLOS Computational Biology. 16 (2): e1007065. doi: 10.1371/journal.pcbi.1007065 . ISSN   1553-7358. PMC   7018098 . PMID   32012146.
  3. 1 2 3 Polich, J. (2007). "Updating P300: An integrative theory of P3a and P3b". Clinical Neurophysiology. 118 (10): 2128–2148. doi:10.1016/j.clinph.2007.04.019. PMC   2715154 . PMID   17573239.
  4. ↑ Keil, A.; Bradley, M. M.; Hauk, O.; Rockstroh, B.; Elbert, T. & Lang, P. J. (2002). "Large-scale neural correlates of affective picture processing". Psychophysiology. 39 (5): 641–649. doi:10.1017/S0048577202394162. PMID   12236331.
  5. ↑ Chapman, R.M. & Bragdon, H.R. (1964). "Evoked responses to numerical and non-numerical visual stimuli while problem solving". Nature . 203 (4950): 1155–1157. Bibcode:1964Natur.203.1155C. doi:10.1038/2031155a0. PMID   14213667. S2CID   4156804.
  6. ↑ Sutton, S.; Braren, M.; Zubin, J. & John, E.R. (1965). "Evoked-Potential Correlates of Stimulus Uncertainty". Science. 150 (3700): 1187–1188. Bibcode:1965Sci...150.1187S. doi:10.1126/science.150.3700.1187. PMID   5852977. S2CID   39822117.
  7. ↑ Sutton, S.; Tueting, P.; Zubin, J. & John, E.R. (1967). "Information delivery and the sensory evoked potential". Science. 155 (3768): 1436–1439. Bibcode:1967Sci...155.1436S. doi:10.1126/science.155.3768.1436. PMID   6018511. S2CID   36787865.
  8. ↑ Comerchero, M. D.; Polich, J. (1999). "P3a and P3b from typical auditory and visual stimuli" (PDF). Clinical Neurophysiology. 110 (1): 24–30. CiteSeerX   10.1.1.576.880 . doi:10.1016/S0168-5597(98)00033-1. PMID   10348317. S2CID   17357823.
  9. ↑ Polich, J. (2003). "Overview of P3a and P3b". In J. Polich (ed.). Detection of Change: Event-Related Potential and fMRI Findings. Boston: Kluwer Academic Press. pp. 83–98.
  10. 1 2 Donchin, E. (1981). "Presidential Address, 1980: Surprise!...Surprise?" (PDF). Psychophysiology. 18 (5): 493–513. doi:10.1111/j.1469-8986.1981.tb01815.x. PMID   7280146.
  11. ↑ Squires, N. K.; Squires, K. C. & Hillyard, S. A. (1975). "Two varieties of long-latency positive waves evoked by unpredictable auditory stimuli in man". Electroencephalography and Clinical Neurophysiology. 38 (4): 387–401. CiteSeerX   10.1.1.326.332 . doi:10.1016/0013-4694(75)90263-1. PMID   46819. S2CID   4614708.
  12. ↑ Farwell LA, Smith SS (January 2001). "Using brain MERMER testing to detect knowledge despite efforts to conceal" (PDF). J Forensic Sci. 46 (1): 135–143. doi:10.1520/JFS14925J. PMID   11210899. Archived from the original (PDF) on 2016-03-17. Retrieved 2016-07-22.
  13. ↑ Piccione F, Giorgi F, Tonin P, et al. (March 2006). "P300-based brain computer interface: Reliability and performance in healthy and paralysed participants". Clin Neurophysiol. 117 (3): 531–537. doi:10.1016/j.clinph.2005.07.024. PMID   16458069. S2CID   24199528.
  14. 1 2 3 Donchin E, Spencer KM, Wijesinghe R (June 2000). "The Mental Prosthesis: Assessing the Speed of a P300-Based Brain–Computer Interface". IEEE Transactions on Rehabilitation Engineering. 8 (2): 174–179. CiteSeerX   10.1.1.133.8980 . doi:10.1109/86.847808. PMID   10896179. S2CID   84043.
  15. ↑ Nijboer F, Sellers EW, Mellinger J, et al. (2008). "A P300-based brain–computer interface for people with amyotrophic lateral sclerosis". Clin Neurophysiol. 119 (8): 1909–1916. doi:10.1016/j.clinph.2008.03.034. PMC   2853977 . PMID   18571984.
  16. ↑ L. A. Farwell & E. Donchin (1988). "Talking off the top of your head: A mental prosthesis utilizing event-related brain potentials" (PDF). Electroencephalogr. Clin. Neurophysiol. 70 (6): 510–523. doi:10.1016/0013-4694(88)90149-6. PMID   2461285. S2CID   4547500. Archived from the original (PDF) on 2017-02-05.
  17. ↑ Hansenne M (August 2000). "Le potentiel évoqué cognitif P300 (II) : variabilité interindividuelle et application clinique en psychopathologie" [The P300 event-related potential. II. Interindividual variability and clinical application in psychopathology]. Clin Neurophysiol (in French). 30 (4): 211–231. doi:10.1016/S0987-7053(00)00224-0. PMID   11013895. S2CID   53176706.
  18. ↑ Bledowski, Christoph; Prvulovic, David; Hoechstetter, Karsten; Scherg, Michael; Wibral, Michael; Goebel, Rainer; Linden, David E. J. (2004-10-20). "Localizing P300 Generators in Visual Target and Distractor Processing: A Combined Event-Related Potential and Functional Magnetic Resonance Imaging Study". The Journal of Neuroscience. 24 (42): 9353–9360. doi:10.1523/jneurosci.1897-04.2004. ISSN   0270-6474. PMC   6730097 . PMID   15496671.
  19. ↑ Nieto, Nicolás; Peterson, Victoria; Rufiner, Hugo Leonardo; Kamienkoski, Juan; Spies, Ruben (2021-04-20). ""Thinking out loud": an open-access EEG-based BCI dataset for inner speech recognition". doi:10.1101/2021.04.19.440473. S2CID   233414714 . Retrieved 2023-04-20.{{cite journal}}: Cite journal requires |journal= (help)
  20. ↑ Liwicki, Foteini Simistira; Gupta, Vibha; Saini, Rajkumar; De, Kanjar; Abid, Nosheen; Rakesh, Sumit; Wellington, Scott; Wilson, Holly; Liwicki, Marcus; Eriksson, Johan (2022-11-30). "Bimodal electroencephalography-functional magnetic resonance imaging dataset for inner-speech recognition": 2022.05.24.492109. doi:10.1101/2022.05.24.492109. S2CID   254126820.{{cite journal}}: Cite journal requires |journal= (help)
  21. ↑ Derkowski, Wojciech; Kędzia, Alicja; Derkowski, Piotr (2016). "THE CLINICAL SIGNIFICANCE OF P300 WAVE IN THE STUDY OF COMPUTER-AVERAGE COGNITIVE EVOKED POTENTIALS". Computer-aided scientific research: 11–17. doi:10.5281/zenodo.10614201.
  22. ↑ Derkowski, Wojciech; Derkowski, Piotr (April 2018). "Signification clinique de l'onde P300 pour le diagnostic et l'évaluation du traitement de la maladie d'Alzheimer et de trouble cognitif léger". Revue Neurologique. 174 (Elsevier Masson): S12–S13. doi:10.1016/j.neurol.2018.01.027.
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