Biomedical subjects

Peter Frost

Publications and source records attributed to Peter Frost.

7 recordsLinked to original sources

PubMed2006

Personality characteristics associated with susceptibility to false memories.

This study examined whether certain personality characteristics are associated with susceptibility to false memories. Participants first answered questions from the Myers-Briggs Type Indicator in order to measure various personality characteristics. They then watched a video excerpt, the simulated eyewitness event. They were next encouraged to lie about the videotaped event during an interview. A week later, some participants recognized confabulated events as being from the video. Two personality characteristics in particular--the introversion-extroversion and thinking-feeling dimensions--were associated with susceptibility to false memories.

Choice Behavior↗

PubMed2005

Is glycated haemoglobin a sensitive index to identify left ventricular dysfunction two months after acute myocardial infarction in normotensive subjects?

BACKGROUND: Glycated haemoglobin concentration (HbA1c) is a marker of glucose metabolism. Glucose intolerance is associated with a high incidence of left ventricular (LV) dysfunction after acute myocardial infarction (AMI). This study was carried out in order to relate HbA1c to LV function two months following AMI in 171 normotensive patients who were not previously known to have had diabetes mellitus. METHODS: Oral glucose tolerance test (GTT) and HbA1c. Echo and Doppler-cardiography were used to measure the E/A (peak velocity of the early filling/atrial contraction waves) at rest and at peak isometric exercise (IME), deceleration time (DT) of E wave, LV ejection fraction (LVEF), LV mass index and diastolic LV function. RESULTS: GTT was diabetic in 20, impaired in 35 and normal in 116 subjects. HbA1c was >6.0% (cut off level for high risk subjects) in 76 patients (67%) with impaired relaxation (E/A<1) during IME and in 30 patients (27%) with restrictive LV filling (identified by E/A=1-2, DT<140 ms). The sensitivity and specificity of HbA1c to predict underlying impaired LV relaxation were 68% and 37%, respectively, and to predict restrictive LV filling were 27% and 98%, respectively. Whereas in univariate analysis, DT.3 was linearly related to HbA1c only (p=0.0002), multiple regression analysis showed that HbA1c was related to LVEF, DT and E/A but not to LVH, LVMI, smoking habit, age, gender and creatinine kinase level during admission for AMI. CONCLUSION: At 2 months after admission for AMI, HbA1c is related to systolic and diastolic LV function but not to LVMI or LVH. HbA1c is a sensitive predictor of impaired relaxation but highly specific to rule out underlying non-restrictive LV filling.

Acute Disease↗

PubMed2005

Left ventricular diastolic function in normotensive subjects 2 months after acute myocardial infarction is related to glucose intolerance.

BACKGROUND: Both glucose intolerance and myocardial infarction are independently associated with impaired left ventricular (LV) function. This study was carried out to relate LV diastolic function in normotensive subjects 2 months after acute myocardial infarction (AMI) to glucose tolerance status. METHODS: Left ventricular ejection fraction (LVEF), LV mass index, peak velocity of the early phase/atrial contraction wave, deceleration time of E wave, and isovolumic relaxation time were measured during echocardiograph/Doppler cardiography in 200 normotensive patients 2 months after AMI. Twenty-nine patients were known to be diabetic on admission with AMI. Glucose tolerance test was carried out in the 171 patients who are not known to be diabetic. RESULTS: Independent of LVEF, restrictive LV filling (peak velocity of the early phase/atrial contraction wave > 1 but < 2 associated with deceleration time of E wave < or = 140 milliseconds) was found in 72% of the known-diabetic patients, 70% of the 20 preclinical diabetic patients, 23% of the 35 patients with impaired glucose tolerance, 13% of the 15 patients with stress hyperglycemia, and 7% of the euglycemic patients (P < .01). In the rest of these patients, LV filling was nonrestrictive. No significant difference was observed in LVEF and LV mass index between patient groups. CONCLUSION: Independent of LVEF, the pattern of abnormal LV filling in normotensive subjects 2 months after AMI is a function of the severity of glucose intolerance, restrictive in the majority of the diabetic patients and nonrestrictive in the majority of the euglycemic patients, impaired glucose tolerance, and stress hyperglycemia. After AMI, abnormal LV filling occurs even in the absence of detectable systolic dysfunction or left ventricular hypertrophy.

Adult↗

PubMed2005

Combination of site of infarct, unrecognized glucose intolerance, and reinfarction after acute myocardial infarction in normotensive subjects is determinant of the development of subsequent systemic hypertension: a pilot study.

BACKGROUND: The natural history of hypertension in healthy normotensive subjects has been described in the Framingham population. We aim to study the rate of progression to hypertension in normotensive subjects after acute myocardial infarction (AMI). METHODS: One hundred seventy-three consecutive normotensive subjects admitted to the Coronary Care Unit with AMI were studied retrospectively with prospective follow-up 4 years after AMI. All the patients who were not known to be diabetic on admission (n = 150) underwent glucose tolerance test (GTT) at 2 months after AMI. RESULTS: Among the 15 patients (8.7%) who developed hypertension, GTT was abnormal in 75% (diabetes = 3, impaired glucose tolerance = 9). There were significantly more Indo-Asians and fewer whites in the hypertensive than in the normotesive patients but they were similar in age and gender, creatinine kinase level, and rate of thrombolysis during admission for AMI. Multiple regression analysis showed that progression to hypertension was a function of the presence of anterior AMI on admission (P = .0297), abnormal GTT (P = .0156), and subsequent MI on follow-up (P = .0122), but was independent of age, gender, smoking habit, body weight, previous MI, thrombolysis, creatinine kinase level, subsequent development of heart failure, and intake of beta-adrenergic blockade or angiotensin-converting enzyme (ACE) inhibitor. Of the hypertensive patients, 47% (n = 7) died compared to 8% (n = 13) of the normotensive subjects (P < .0001). CONCLUSIONS: Progression to hypertension in normotensive subjects after AMI is determined by a combination of the site of the infarct, GTT 2 months after AMI, and subsequent development of a second MI. Systemic hypertension after AMI is associated with a high mortality.

Aged↗

PubMed2004

Impaired left ventricular diastolic function during isometric exercise in asymptomatic patients with hyperlipidaemia.

BACKGROUND: Left ventricular (LV) diastolic dysfunction is an early sign, and may be more sensitive indicator, of ischaemic heart disease (IHD) than systolic dysfunction. METHODS: LV diastolic function was assessed during isometric exercise (IME) in 37 consecutive normotensive hyperlipidaemics (LIP), without cardiac history or symptoms. Each patient underwent a stress ECG test and 2-D echo and Doppler cardiography. During the latter, transmitral flow at rest and at peak standardised IME using handgrip was studied. From the tracings, the E/A (peak velocity of the early/atrial components), the contribution of atrial systole to LV filling (ACF), the deceleration time (DT) of the E wave and the isovolumic relaxation time (IVRT) were calculated. Results were compared to 37 age-matched normal healthy volunteers (NOR). RESULTS: Resting E/A was not different between NOR and the LIP. A significant reduction in E/A with IME was observed in LIP but not in NOR. Impaired LV filling (shown by E/A<1) was demonstrated in five patients (13%) at rest and in 20 patients (54%) at peak IME. All NOR had E/A>1 suggesting normal LV filling. Fifteen of the 30 patients with negative stress ECG test demonstrated LV diastolic dysfunction. ACF was higher in LIP than NOR and increased significantly (P<0.005) by 23% during IME. DT and IVRT in LIP were not different from NOR. In neither NOR nor LIP, were the LV diastolic functional parameters related to gender, smoking habit or levels of total cholesterol, LDL- or HDL-cholesterol or triglycerides. CONCLUSION: The prevalence of LV diastolic dysfunction in asymptomatic patients with hyperlipidaemia despite a negative stress ECG test may be evidence of early underlying pre-clinical myocardial ischaemia.

Adult↗

PubMed2003

Increasing false recognition rates with confirmatory feedback: a phenomenological analysis.

During a simulated witness interrogation, participants were encouraged to confabulate an account consistent with false information concerning a videotaped event. The interviewer verbally affirmed some false responses. Previous research has shown that, a week later, participants often recognize confabulated events that were affirmed by the experimenter as being from the video. What is unclear is whether confirmatory feedback encouraged a change in the mental representation of the confabulated events to fit the original event or confirmation might have merely encouraged a change in beliefs about the event. To further understand the mechanisms that underlie the confirmatory feedback effect, participants were asked to judge the phenomenological experience associated with false recognition.

Adult↗

PubMed2002

Why misinformation is more likely to be recognised over time: A source monitoring account.

Although memory for actual events tends to be forgotten over time, memory for misinformation tends to be retrieved at a stable rate over long delays or at a rate greater than that found immediately after encoding. To examine whether source monitoring errors contribute to this phenomenon, two experiments investigated subjects' memory for the source of misinformation at different retention intervals. Subjects viewed a slide presentation, read a narrative containing misinformation, and, either 10 minutes or 1 week later, completed a recognition test about details seen in the slides and about the source of these details. After the longer retention interval in both experiments, participants were more likely to agree that they had seen misleading information and were also more likely to incorrectly associate the misinformation with the slide event. Theoretical implications of these findings are considered.

Adult↗