Overgeneralization of autobiographical memory strategies in cannabis users and multiple psychoactive substance consumers

Objectives

Psychoactive substance consumption induces cognitive impairments in terms of episodic memory and attentional and executive function deficits. This study aims to investigate whether the recall of autobiographical memories is disturbed in substance consumers, and in particular whether those patients tend to evoke memories at a general level rather than at a specific level when confronted by an emotional cue word. Furthermore, we aim to verify whether adopting a more general memory retrieving style is a dynamic phenomenon and if it depends on the type of substance consumed.

Design and methods

The participants of this research were 51 cannabis users, including 17 occasional cannabis users, 17 cannabis abusers and 17 individuals addicted to cannabis. They were compared to 18 multiple substance-dependent individuals and to 38 nondependent individuals. Participants were subjected to the Williams and Scott (1988) [39] autobiographical memory test. After an assessment of the mode of substance consumption, several clinical dimensions were measured, such as depression (BDI), anxiety (STAI Y A and B), alexithymia (TAS 20) and episodic memory (RLS-15).

Results

The results show that the percentage of general positive and negative memories recalled increases progressively as the consumption takes on the characteristics of addictive behavior, while we observe no deficit in episodic memory. The level of alexithymia evolved in parallel with the percentage of general memories. These results are not dependent on the type of substance used and can not be explained by the level of depression.

Conclusions

Overgeneralization is a phenomenon observable in psychoactive substance consumers, whatever the type of substances used, which sets in progressively as the dependence develops. Our results show that overgeneralization is not only due to an impairment of mnesic abilities, implying that this phenomenon could be underlined by several mechanisms. The role of overgeneralization as a functional avoidance established in attempt to protect individuals from emotion resurgence is discussed. Furthermore, the impact of deficits in executive functions on the recall of autobiographical memories in substance abusers has not been studied and would be an interesting path of research.     

Memory improvement in patients with temporal lobe epilepsy at one-year postoperative

Introduction

Several studies have assessed the impact of surgery on both anterograde and remote memory in patients with temporal lobe epilepsy (TLE). The majority of results have shown an extensive memory deficit in patients after temporal resection (TL). However, few protocols have used a prospective longitudinal design. Moreover, the postoperative delays were variable from one study to the next, instead of regular monitoring to identify the potential effect of time elapsed after surgery on memory performance. In addition, some studies have not used strict inclusion criteria to establish homogeneous patient groups. Finally, the impact of surgery on memory has been often assessed by comparing memory skills between epileptic patients and healthy controls. Our aim was to examine the impact of TL on memory in patients with TLE, recruited according to clear-cut clinical criteria. Moreover, we focused on memory performance progression per se in epileptic patients pre- and postoperatively, rather than on memory performance analysis expressed as “deficient” or “normal”.

Methods

We assessed 30 patients with unilateral TLE (17 right TLE and 13 left TLE) on four anterograde memory tests and six remote memory tasks. Patients completed all tests preoperatively, and 5 and 12 months after TL.

Results

Five months after surgery, performance was equivalent to the preoperative scores for both groups in anterograde memory tasks and remote memory tests. One year after TL, patients with right TLE showed enhanced performance in the verbal anterograde memory tests and in retrieving recent autobiographical memories. Results for left TL showed improved scores only in a recognition memory test of faces.

Conclusions

In the present study, surgical patients were “double winners” gaining seizure freedom and potential of memory stability or recovery. The gain was observed only 12 months after surgery and following temporal resection lateralisation. Our data showed postoperative memory improvement in patients with temporal lobe epilepsy presenting with specific clinical characteristics.     

Ethics and dementia: a three years' experience of a French "Alzheimer's ethico-clinic workshop"

There is a growing interest concerning ethical questions. This ethical need is the more important in the field of dementia. Indeed, the ethical concerns related to this field are highly specific, which leaves some of our questions without pertinent answers. METHODS: After three years of experience, it is a good time to assess the Alzheimer ethico-clinic workshop created by a French memory centre (in Grenoble) and encouraged by the French national Alzheimer disease plan. RESULTS: Since their implementation, we have recorded 24 monthly coordination meetings, 10 of which have been held through videoconferences with various participants. Most of the time during the workshops, clinical situations that are experienced in our daily activities are brought up by one of us and then exposed for collective discussion. If no practical situation is available, we organize the meetings through critical readings of texts of law or through comments on articles dealing with Ethics. We retain four main ethical topics: the information given to the patient and his family, the acceptance of the person, the balance of benefits/risks and one's individual ethics as opposed to the ethics of a group. At this point in time, we are pleased with the organization of these workshops and feel that they meet our expectations. Thanks to the diverse experiences and activities of each participant, the discussions on Ethics are of high quality. PROSPECTIVES: As a place of shared discussions/thoughts, these ethical workshops could constitute a reference to be used when making decisions in complex situations. Other than the importance of the ethical questions that are raised, it should encourage open-minded attitudes and enrich the actions of each of us by making us more aware of the ethical concerns in daily situations. Finally, these workshops could be a field of research for theses, dissertations and answer the training and research needs of a memory centre.     

Working memory in schizophrenia: a review

INTRODUCTION: Working memory refers to a limited capacity system for temporary storage and processing of information that is known to depend on the integrity of the prefrontal cortex. It has been classically described as composed of a "central executive" that performs control, selection and planning functions, and two "slave" systems: on the one hand, the phonological loop that holds verbal, speech-based representations, and on the other hand, the visuospatial sketchpad that manipulates spatial and object visual representations. LITERATURE FINDINGS: Studies in schizophrenia have used different tasks that tap different processes within the working memory. Despite the variety of measures, there is solid neuropsychological evidence that patients with schizophrenia demonstrate deficits in all subsystems of working memory. Several studies have shown no correlations between working memory deficits and age, gender, premorbid IQ, duration of disease or positive syndrome, but a correlation has been found with a low-educational level, and negative and disorganization symptoms. Neuroimaging studies have provided evidence of an involvement of the dorsolateral-prefrontal cortex during working memory performance. Many studies have demonstrated a functional deficit in this area. However, several recent studies have reported either equal or increased activation of the dorsolateral-prefrontal cortex in schizophrenia during working memory performance. Working memory deficits are present early in the course of schizophrenia and they have been shown to be consistently associated with reduced levels of elementary social skills and learning capacity. Unaffected relatives of individuals with schizophrenia and individuals diagnosed with schizotypal personality demonstrate deficits in tasks designed to measure working memory function. Working memory dysfunctions might be suitable candidate markers for vulnerability. Certain executive sub-processes seem to be the most heritable component of the working memory. Working memory deficits in schizophrenia may benefit from specific stimulation of receptors such as the dopaminergic D1 receptor, adrenergic alpha-2A receptor or nicotinic receptors. Few studies on the effect of antipsychotic medication on working memory in schizophrenia have been carried out and their results are highly variable. Atypical antipsychotic drugs, notably risperidone, have appeared to improve performance in working memory tasks. Cognitive exercises can improve working memory with a six-month persistent effect.     

Le voyage de Victor Hugo aux Pyrénées, un voyage dans la mémoire

1843 can be considered as a turning point in the life of Victor Hugo. Certainly in the middle of his life he had experienced dramatic events specifically the failure of his play Les Burgraves, the wedding of his daughter Leopoldine and more importantly her tragic death by drowning in the Seine at Villequier in September of the same year. These events had important psychological and emotional effects on him. We have tried to identify what affected Victor Hugo's unconscious thought processes by analysing different texts linked to these happenings, primarily the account of the journey referred to as Pyrenees by the executors of his will. This analysis leads us to establish a link with the drawings of Victor Hugo in which unconscious processes are already expressed by « l’homme ocean ». But if the purpose of our study is above all a psychoanalytical understanding of the process leading to involuntary memory, the « proustian memory », we are trying to replace this process in Victor Hugo's existential context, in the moment between the before and the after.     

Recovery from hypoxia and ECS-induced amnesia after a single exposure to training environment

A single exposure to the training environment for 3 min was sufficient to produce recovery from hypoxia-induced amnesia when tested 30 min later. Recovery from ECS-induced amnesia was evidenced 5 min after exposure to the training environment. The results make a state dependent learning explanation for memory loss after ECS or hypoxia unfeasible, since the recovery is seen immediately after the memory loss is evidenced. The author proposes that amnestic treatments prevent the integration of the training event into existing functional memory systems and consequently the training has no significance for the animal. Reexposure to the training environment precipitates a continuation of these integrative processes and the memory becomes organized in such a way that it has a behavioral consequence (avoidance) on the subsequent trial.     

La mémoire : une clé de voûte dans l’œuvre de Jean Delay

Known worldwide as the discover of neuroleptics, Jean Delay (1907–1987) dedicaded an important part of his work to memory. First his medical thesis entitled astereognosies is focused on the touch disorders. This work has been followed by a thesis of philosophy under the leadership of Pierre Janet, about memory disorders. Jean Delay proposed a classification of neurological and psychiatric memory disorders taking heed to Maurice Halbwachs’ work on collective memory. And the end of his life, as a writer, Jean Delay led an ambitious project. Thanks to his researches in French national Archives, he published in four volumes the history of his maternal ancestors from XVIth to XIXth century. This work has several connections with two of Marguerite Yourcenar's books: Dear Departed: A Memoir and How Many Years: A Memoir. Jean Delay supported the election of Marguerite Yourcenar at L’Académie française, the first woman to be elected at the prestigious French institution. Psychological traits of Jean Delay are also drawn in this paper.