The purpose of this study was to define the validation methods and outcomes of a conductance catheter system specifically for in vivo murine cardiac hemodynamic analysis. To express the relationship between conductance and blood volumes, we used an in vitro model to derive a volume-conductance line. The volume-conductance line was used to compute raw volume from the modified conductance signals. The parallel volume was calibrated with hypertonic (15%) saline injected from extrajugular vein. The ventricular volume was computed by raw volume minus parallel volume. The accuracy of conductance volumetric measurements was validated with a static in situ infusion of calibrated volumes of whole blood injected into arrested left ventricles. In vivo dynamic measurements were performed with 24 C57B1/6 mice, 6 months old; for comparison of established values. The in situ model showed that after calibration, the experimental coefficient, alpha, was equal to 1 and the measured volume by conductance catheter was equal to the true volume of the left ventricle (y = 0.982x + 0.513, p < .0001). For the in vivo models, the end-diastolic volumes and the stroke volumes and cardiac output determined with the conductance catheter system were 17.3 +/- 1.0 microL, 10.6 +/- 0.9 microL, and 6.0 +/- 0.5 mL/min, respectively. We validated the relationship between measured volume by conductance catheter and the true volume and demonstrated the accuracy of the volume-conductance line for conversion of conductance to volume.

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During advanced meditative practices, unusual perceptions can arise including the sense of receiving information about unknown people who are deceased. As with meditation, this mental state of communication with the deceased involves calming mental chatter and becoming receptive to subtle feelings and sensations. Psychometric and brain electrophysiology data were collected from six individuals who had previously reported accurate information about deceased individuals under double-blind conditions. Each experimental participant performed two tasks with eyes closed. In the first task, the participant was given only the first name of a deceased person and asked 25 questions. After each question, the participant was asked to silently perceive information relevant to the question for 20 s and then respond verbally. Responses were transcribed and then scored for accuracy by individuals who knew the deceased persons. Of the four mediums whose accuracy could be evaluated, three scored significantly above chance (p < 0.03). The correlation between accuracy and brain activity during the 20 s of silent mediumship communication was significant in frontal theta for one participant (p < 0.01). In the second task, participants were asked to experience four mental states for 1 min each: (1) thinking about a known living person, (2) listening to a biography, (3) thinking about an imaginary person, and (4) interacting mentally with a known deceased person. Each mental state was repeated three times. Statistically significant differences at p < 0.01 after correction for multiple comparisons in electrocortical activity among the four conditions were obtained in all six participants, primarily in the gamma band (which might be due to muscular activity). These differences suggest that the impression of communicating with the deceased may be a distinct mental state distinct from ordinary thinking or imagination.

Unresolved, complicated, prolonged, or traumatic grief can have detrimental effects on mental and/or physical health. The effects of traditional grief counseling, with its focus on the client's acceptance of separation and integration of loss, are unclear. Within the model of continuing bonds, however, grief resolution includes an ongoing relationship between the living and the deceased. Spontaneous and induced experiences of after-death communication (ADC) have been shown to be beneficial in the resolution of grief by demonstrating these continued bonds. Presently, many bereaved individuals are experiencing assisted ADCs by receiving readings from psychic mediums and though little is known about the effects of this selfprescribed treatment option, anecdotal reports and exploratory data posit a positive outcome. This article aims to inform those who work with the bereaved about the relationships between grief, spontaneous, induced, and assisted ADC experiences, and the continuing bonds paradigm. Suggestions for future research are also included.