مجال
التميز
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تميز دراسي
وبحثي
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البحث (1):
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عنوان البحث:
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The cost of space independence in
P300 BCI spellers
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رابط البحث:
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Click here
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تاريخ النشر:
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29/07/2013
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موجز عن البحث:
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Background: Though non-invasive
EEG-based Brain Computer Interfaces (BCI) have been researched extensively
over the last two decades, most designs require control of spatial attention
and/or gaze on the part of the user.
Methods: In healthy adults, we
compared the offline performance of a space-independent P300-based BCI for
spelling words using Rapid Serial Visual Presentation (RSVP), to the
well-known space-dependent Matrix P300 speller.
Results: EEG classifiability with the
RSVP speller was as good as with the Matrix speller. While the Matrix
speller’s performance was significantly reliant on early, gaze-dependent
Visual Evoked Potentials (VEPs), the RSVP speller depended only on the
space-independent P300b. However, there was a cost to true spatial
independence: the RSVP speller was less efficient in terms of spelling speed.
Conclusions: The advantage of space
independence in the RSVP speller was concomitant with a marked reduction in
spelling efficiency. Nevertheless, with key improvements to the RSVP design,
truly space-independent BCIs could approach efficiencies on par with the
Matrix speller. With sufficiently high letter spelling rates fused with
predictive language modelling, they would be viable for potential
applications with patients unable to direct overt visual gaze or covert
attentional focus.
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البحث (2):
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عنوان البحث:
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Subliminal Salience Search
Illustrated: EEG Identity and Deception Detection on the Fringe of Awareness
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رابط البحث:
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Click here
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تاريخ النشر:
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23/01/2013
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موجز عن البحث:
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We propose a novel deception
detection system based on Rapid Serial Visual Presentation (RSVP). One
motivation for the new method is to present stimuli on the fringe of
awareness, such that it is more difficult for deceivers to confound the
deception test using countermeasures. The proposed system is able to detect
identity deception (by using the first names of participants) with a 100% hit
rate (at an alpha level of 0.05). To achieve this, we extended the classic
Event-Related Potential (ERP) techniques (such as peak-to-peak) by applying
Randomisation, a form of Monte Carlo resampling, which we used to detect
deception at an individual level. In order to make the deployment of the
system simple and rapid, we utilised data from three electrodes only: Fz, Cz
and Pz. We then combined data from the three electrodes using Fisher’s method
so that each participant was assigned a single p-value, which represents the
combined probability that a specific participant was being deceptive. We also
present subliminal salience search as a general method to determine what
participants find salient by detecting breakthrough into conscious awareness
using EEG.
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البحث (3):
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عنوان البحث:
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Countering
Countermeasures: Detecting Identity Lies by Detecting Conscious Breakthrough
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رابط إلى البحث:
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Click here
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تاريخ النشر:
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01/02/2014
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موجز عن البحث:
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One major drawback
of deception detection is its vulnerability to countermeasures, whereby
participants wilfully modulate their physiological or neurophysiological
response to critical guilt-determining stimuli. One reason for this
vulnerability is that stimuli are usually presented slowly. This allows
enough time to consciously apply countermeasures, once the role of stimuli is
determined. However, by increasing presentation speed, stimuli can be placed
on the fringe of awareness, rendering it hard to perceive those that have not
been previously identified, hindering the possibility to employ
countermeasures. We tested an identity deception detector by presenting first
names in Rapid Serial Visual Presentation and instructing participants to lie
about their own identity. We also instructed participants to apply a series
of countermeasures. The method proved resilient, remaining effective at
detecting deception under all countermeasures.
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البحث (4):
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عنوان البحث:
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Resampling the
peak, some dos and don’ts
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رابط إلى البحث:
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Click here
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تاريخ النشر:
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12/10/2014
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موجز عن البحث:
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Resampling
techniques are used widely within the ERP community to assess statistical
significance and especially in the deception detection literature. Here, we
argue that because of statistical bias, bootstrap should not be used in
combination with methods like peak-to-peak. Instead, permutation tests
provide a more appropriate alternative.
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المؤتمرات العلمية:
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المؤتمر (1):
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عنوان المؤتمر:
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Computational
Neuroscience (CNS2013)
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تاريخ الإنعقاد:
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13/07/2013
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بلد
ومكان الإنعقاد:
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Paris,
France
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طبيعة المشاركة:
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Poster
presentation
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عنوان المشاركة
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A new
method for detecting deception in Event Related Potentials using individual-specific
weight templates
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موجز عن المشاركة
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A new
method called the weight template (WT) is proposed for classifying Event
related potentials (ERPs) into deveining and non-deceiving. In this study, EEG data of two P300-based
lie detection experiments were analyzed to demonstrate the efficiency of the WT method in
detecting deception in comparison with
a common method used to measure P300 lie detection called Peak-to-Peak which
is believed to be more accurate than other methods in diagnosing P300
amplitude of ERP lie detection [1],[2]. One experiment consisted of
presenting participants with birth dates stimuli and 12 participants were
instructed to lie about their birth days. The other one was taken from this
research [3] and consisted of 15 participants who were instructed to lie
about their first names. The performances of the WT alongside with
Peak-to-Peak method were examined using the recorded EEG data at Pz
electrode. Using simulated EEG data[4], the Receiver Operating Characteristic
(ROC) curve analysis was also performed to examine the efficiency of the
proposed method in detecting deception in low signal-to-noise ERPs.
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المؤتمر (2):
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عنوان المؤتمر:
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BACN-2014
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تاريخ الإنعقاد:
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11-12/09/2014
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بلد
ومكان الإنعقاد:
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York,
United Kingdom
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طبيعة المشاركة:
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Poster
presentation
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عنوان المشاركة
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Detecting
Deception in event related potentials using individual’s weight template
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موجز عن المشاركة
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We
propose a method for classifying Event related potentials (ERPs), which we
call the Weight Template (WT). In this study, EEG data from two P300-based
lie detection experiments were analyzed to demonstrate the efficiency of the
WT method in detecting deception. Typically, P300-based lie detection systems
employ the P300 component to detect concealed information. They present three
stimulus types: Probes (P), which represent concealed information,
Irrelevants (I), which are frequent and task-irrelevant, and Targets (T),
which are irrelevant items, but participants are asked to do a task whenever
they see a Target. The principle underlying the WT method is that as the
Target stimulus is task-relevant, it will evoke a robust P300 pattern for
each subject, which we hypothesize is characteristic in form and polarity of
that individual’s P300. Accordingly, this T ERP can serve as an
individual-specific template, with which to search for the Probe P300.
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المؤتمر (3):
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عنوان المؤتمر:
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IOP2014
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تاريخ الإنعقاد:
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24/09/2014
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بلد
ومكان الإنعقاد:
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Hiroshima-Japan
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طبيعة المشاركة:
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Poster
presentation
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عنوان المشاركة
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Detecting
salience on the fringe of awareness using the P300
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موجز عن المشاركة
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In
(Bowman et al., 2013; Bowman et al., 2014), we showed that presenting stimuli
on the fringe of awareness using Rapid Serial Visual Presentation (RSVP),
provides an effective method to detect identity deception. In particular, we
showed that RSVP salient stimuli (i.e. a participant’s own name) could break
through awareness, resulting in the generation of a P300 component, which
could reliably be used to differentiate between deceivers and non-deceivers.
Consequently, we have named our proposed method, the Fringe (or P3-Rapid)
identity detector.
In our
experiment here, the aim was to investigate the effectiveness of the
Fringe/P3-Rapid method, in response to intrinsically salient stimuli, that
are not as exquisitely salient as own-name. To demonstrate this, we presented
RSVP streams containing familiar and unfamiliar names. Three critical stimuli
were presented: Probe (famous names), Irrelevant (unfamiliar, or random
names), and Target (an irrelevant name that is task-relevant, as participants
were instructed to perform a task whenever they saw this Target). All names
were presented at a speed of 133ms per stimulus. As the aim was to explore
the sensitivity of the proposed method in detecting intrinsic salience,
participants were not told about the presences of the famous names. That is,
there was no task associated with the famous names. They were only instructed
to look for the Target name. Our hypothesis was that, as the Probes represent
salient stimuli, they would elicit a distinct brain response from that
generated by an Irrelevant.
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