Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[Q]: Context: Event-related potentials (ERPs) are sensitive measures of both perceptual and cognitive processes. The aim of the present study was to identify brain regions involved in the processes of cognitive dysfunction in narcolepsy by means of ERP tomography.', 'In 17 drug-free patients with narcolepsy and 17 controls, ERPs were recorded (auditory odd-ball paradigm). Latencies, amplitudes and LORETA sources were determined for standard (N1 and P2) and target (N2 and P300) ERP components. Psychometry included measures of mental performance, affect and critical flicker fusion frequency (CFF).', 'In the ERPs patients demonstrated delayed cognitive N2 and P300 components and reduced amplitudes in midline regions, while N1 and P2 components did not differ from controls. LORETA suggested reduced P300 sources bilaterally in the precuneus, the anterior and posterior cingulate gyri, the ventrolateral prefrontal cortex and the parahippocampal gyrus. In psychometry, patients demonstrated deteriorated mood, increased trait anxiety, decreased CFF and a trend toward reduced general verbal memory and psychomotor activity.
Answer: Narcoleptic patients showed prolonged information processing, as indexed by N2 and P300 latencies and decreased energetic resources for cognitive processing.
[A]: Does event-related-potential low-resolution brain electromagnetic tomography ( ERP-LORETA ) suggest decreased energetic resources for cognitive processing in narcolepsy?

[Q]: Context: The aim of this study was to determine the clinical significance and prognostic impact of extranodal metastasis (EM) in gastric carcinoma.', 'The study included 1023 patients who underwent gastrectomy with lymphadenectomy for primary gastric carcinoma between January 1993 and December 1996. EM was defined as the presence of tumour cells in extramural soft tissue that was discontinuous with either the primary lesion or locoregional lymph nodes.', "EM was detected in 146 (14.3 per cent) of the 1023 patients and in 1060 (3.0 per cent) of the 35 811 nodules that were retrieved as 'lymph nodes' from adipose connective tissues. The incidence of EM was significantly higher in patients with tumours that were large (diameter 10 cm or more), infiltrative, deeply invading or undifferentiated and in those with lymph node, peritoneal or liver metastases, or lymphatic or vascular involvement. After curative operation overall survival was significantly worse for patients with EM than those without (P < 0.001). Multivariate analysis identified EM as an independent prognostic factor (hazard ratio 1.82 (95 per cent confidence interval 1.23 to 2.71); P = 0.003).
Answer: EM is an independent prognostic factor and should therefore be included in the tumour node metastasis (TNM) staging system.
[A]: Is extranodal metastasis an indicator of poor prognosis in patients with gastric carcinoma?

[Q]: Context: A recent meta-analysis showed that obstructive sleep apnea (OSA) is associated with a higher prevalence of cancer and cancer-related mortality; however, little information is available on the association between OSA and colorectal neoplasia.', 'We identified consecutive patients who underwent overnight polysomnography (PSG) and subsequent colonoscopy. We compared the prevalence of colorectal neoplasia between patients with or without OSA according to the results of PSG. For each patient with OSA, 1 or 2 controls matched for age (5 years), sex, body mass index (BMI), and smoking who had undergone first-time screening colonoscopy were selected.', 'Of the 163 patients, 111 patients were diagnosed with OSA and 52 patients were within the normal range of the Apnea-Hypopnea Index. Of the 111 patients with OSA, 18 patients (16.2%) had advanced colorectal neoplasia, including 4 (3.6%) colorectal cancers. In the multivariate analyses, OSA was associated with an increased risk of advanced colorectal neoplasia after adjusting for factors including age and sex (mild: odds ratio[OR], 14.09; 95% confidence interval [CI], 1.55-127.83; P= .019; moderate or severe: OR, 14.12; 95% CI, 1.52-131.25; P= .020). Our case-control study revealed that the odds of detecting advanced colorectal neoplasia among patients with OSA were approximately 3.03 times greater than in the controls matched for age, sex, BMI, and smoking (OR, 3.03; 95% CI, 1.44-6.34; P= .002).
Answer: Physicians should be aware of the association between OSA and the development of colorectal neoplasia and explain the need for colonoscopy to patients with OSA.
[A]:
Is obstructive sleep apnea associated with an increased risk of colorectal neoplasia?