Experimental production of illusory (false) memories in reconstructions of narratives: effect size and potential mediation by right hemispheric stimulation from complex, weak magnetic fields

Everyday Memory in Patients with Alzheimer's Disease: Fragmentary and Distorted

BACKGROUND

Errors of omission are an established hallmark of memory impairment in Alzheimer's disease (AD). Much less is known about other memory errors in AD such as false memories.

OBJECTIVE

We investigated false memories in healthy elderly controls (HC; n = 23) and patients with AD (n = 20) using real-life tasks of watching news and commercials.

METHODS

Participants received a comprehensive neuropsychological assessment and were shown original news and commercials with a subsequent recognition task to assess veridical and false memories.

RESULTS

Subjective estimate of the number of errors were alike in HC and patients with AD. However, memory performance in both the news and the commercials task was significantly worse in patients with AD. Trail-Making Test and Symbol-Span Test were significant predictors of false memories on viewing news and commercials. In patients with AD, levels of Aβ1 - 42, but not levels of tau-protein were correlated with false memories in both tasks.

CONCLUSIONS

Everyday life in patients with AD is impeded not due to the incompleteness of memory but also due to its distortions. Furthermore, it is hindered by the lack of awareness towards these deficits. False memory content in patients with AD is associated with Aβ42 levels in the CSF as a surrogate of the overall extent to which the brain has been affected by AD pathology. Future studies will need to address the impact of this duality of memory failure on everyday life of patients with AD and their proxies in greater detail.

What's in a Name for Memory Errors? Implications and Ethical Issues Arising From the Use of the Term "False Memory" for Errors in Memory for Details

The term "false memories" has been used to refer to suggestibility experiments in which whole events are apparently confabulated and in media accounts of contested memories of childhood abuse. Since 1992 psychologists have increasingly used the term "false memory" when discussing memory errors for details, such as specific words within lists. Use of the term to refer to errors in details is a shift in language away from other terms used historically (e.g., "memory intrusions"). We empirically examine this shift in language and discuss implications of the new use of the term "false memories." Use of the term presents serious ethical challenges to the data-interpretation process by encouraging over-generalization and misapplication of research findings on word memory to social issues.

Enhancement of images of possible memories of others during exposure to circumcerebral magnetic fields: correlations with ambient geomagnetic activity

On the basis of results from a special subject who reported information at a distance during exposure to weak, circumcerebral magnetic fields rotating within the horizontal plane, we designed an experiment to discern if the subjective narratives of normal people exposed to these fields could be similar to the comments of emotionally related individuals who were concurrently generating shared memories about a randomly selected stimulus. Blind matching of the comments indicated that the proportions of 44 students who accurately paired the narratives of the field-exposed subject and the comments of the stimulus person as congruent were statistically significant for 5 of the 7 pairs whose narratives were of sufficient length for analysis. The ratings for congruence of the pairs of verbal behaviors for the 7 pairs of subjects were negatively correlated (rho = -.72) with the geomagnetic activity during the 24-hr. interval within which the experiences were conducted. The results suggested consciousness might also be an insulator to myriad stimuli which might be accessible when brain activity is modified by circumcerebral magnetic fields with temporal configurations in the order of 20 msec.

Experimental facilitation of the sensed presence: possible intercalation between the hemispheres induced by complex magnetic fields

This experiment was designed to test the hypothesis that the sensed presence, the feeling of a proximal sentient being, can be evoked within the laboratory. Under double-blind conditions, 48 university men and women were exposed to weak (100 nT to 1 muT), complex, pulsed magnetic fields that were applied primarily over the right temporoparietal region, primarily over the left temporoparietal region, or equally across both hemispheres (one treatment per group) for 20 minutes while wearing opaque goggles in a very quiet room. A fourth group was exposed to a sham-field condition. Subjects who received greater stimulation over the right hemisphere or equal stimulation across both hemispheres reported more frequent incidences of presences, fears, and odd smells than did the subjects who received greater stimulation over the left hemisphere or who were exposed to the sham-field condition. The results suggest that the sensed presence is subject to experimental manipulation. This experimental procedure could be employed to explore the idea that the experience of a sensed presence is a resident property of the human brain and may be the fundamental source for phenomena attributed to visitations by gods, spirits, and other ephemeral phenomena.

Geophysical variables and behavior: XCVIII. Ambient geomagnetic activity and experiences of "memories": interactions with sex and implications for receptive psi experiences

During 96 nonsequential days over a 3-yr. period, a total of 53 men and 86 women were exposed only once for 30 min. to transcerebral, weak complex magnetic fields while they sat alone within a quiet chamber. They were asked to record the frequency of specific experiences after the exposure was completed. There was a significant interaction between sex and global geomagnetic activity for the incidence of experiences attributed to memories. Women reported more experiences attributed to "childhood memories" when geomagnetic activity was less than 20 nT, while men reported more of these experiences when the activity was more than 20 nT. Re-analyses of a database of "paranormal experiences" reported by 395 separate individuals over a 100-yr. period indicated that more men than women reported "precognitive experiences" on days the geomagnetic activity was above 20 nT while women reported such experiences if the geomagnetic activity was below 20 nT. These results suggest that these experiences, be they veridical or illusory, may be influenced by global geomagnetic activity that affect the neuroelectrical or neurochemical processes associated with memory consolidation or the attribution of the serial order of experiences during retrieval.