Temporosylvian arachnoid cysts in children. Part 2: Postoperative neuropsychological and clinical improvement.

OBJECTIVE: The authors' objective was to study clinical, imaging, and neuropsychological changes in children who underwent surgery for a temporal arachnoid cyst (TAC). METHODS: Thirty-four children were prospectively assessed similarly at diagnosis and postoperatively (mean 14 months) with clinic visits, images, cognitive tests, and parental questionnaires on mood/behavior and executive functions. The scores were compared pre- and postoperatively for the entire cohort and individually. The scores of 25 children were also compared with a control group of 23 healthy age-matched children. Parents were administered an outcome questionnaire on average 4 years postoperatively. RESULTS: The 34 children selected for surgery had signs of raised intracranial pressure (74%) and/or selective neuropsychological disorders presumably linked to cyst location (learning difficulties in 65%, cognitive difficulties in 56%, and mood/behavior difficulties in 47%). The majority of patients had a convex cyst (85%) and underwent microsurgical fenestration (85%). The TAC volume decreased ≥ 50% for 59% of children. On the Wechsler Intelligence Scale, the entire cohort significantly improved on Full Scale IQ and verbal and perceptual nonverbal indexes. Individually, nearly half of the children (47%) highly increased their scores (≥ 15 points) on at least one IQ index and 26% on at least two indexes. Language, working memory, episodic memory, and executive functions were also significantly improved. Improvements were more pronounced in patients with a preoperative heterogeneous profile with isolated lower scores and a left-sided cyst. Parental questionnaires showed reduction in anxiety, aggressiveness, social problems, and daily life executive disorders. Preschool-aged children improved significantly in language and verbal IQ, as did middle/high school-aged children in many domains. Individual analyses revealed improvement in 76% of cases. Cognitive scores were lower for patients preoperatively than for controls and were no longer significantly different postoperatively in verbal fluency, visual memory, and working memory. Four years later, 97% of parents described an improvement in their child, correlated with cognitive improvements. CONCLUSIONS: Among children with a TAC, some have no clinical signs or neuropsychological difficulties, and others may show signs of raised intracranial pressure and/or specific neuropsychological disorders that impact daily life and require significant and long-lasting rehabilitation. In these cases, consideration may be given to surgical decompression. It is interesting to note that 76% of this surgically treated cohort improved regardless of the child's age, particularly in patients with selective disorders and an impact on daily life. However, a larger number of children will need to be investigated before the true benefit of such treatment can be known.

Temporosylvian arachnoid cysts in children. Part 1: Cognitive profile of children with a temporal cyst and impact of the cyst in daily life. A prospective study in 100 consecutive children.

OBJECTIVE: The aim of this study was to determine the cognitive profile of children with a temporal arachnoid cyst (TAC) and its impact on daily life. METHODS: The authors prospectively analyzed the cognitive and psychological profiles of 100 consecutive children relative to age and cyst characteristics (side, cyst size, and cyst shape: convex or nonconvex) and their outcome 4 years later. RESULTS: Mean IQs were normal but with high heterogeneity on Full Scale IQ (FSIQ; range 59-150); 29% of children had at least one Wechsler index below the norm, in particular, Processing Speed and Working Memory Indexes. Impairments were observed in language for 31% of children, as well as in verbal memory (28%), visual memory (23%), executive function (21%), and visual attention (24%). Half of the children (50%) needed rehabilitation for learning difficulties, and 26% had academic difficulties. The parental questionnaire BRIEF (Behavior Rating Inventory of Executive Function) revealed significant executive dysfunctions in daily life for 22% of the children. One-third of the patients (34%) required psychotherapy for anxiety or social disorders, with higher rates in patients with a right-sided cyst and older children. Cyst size had very little neuropsychological impact. Convex cysts were significantly associated with worse performance than nonconvex cysts on all Wechsler indexes and FSIQ, and in language, verbal memory, attention, and visuospatial skills. Children with a convex cyst had significantly more executive and behavior difficulties in daily life and more psychotherapy than other children. The effect of cyst shape was independent of Galassi type and cyst side. Children with a ruptured cyst or an incidentally discovered cyst usually had a good cognitive level. Four years later, children without initial disorders remained stable, whereas those with difficulties who did not undergo surgery needed more rehabilitation and school adaptations. CONCLUSIONS: This large cohort study revealed a varied profile of children with a TAC: at initial assessment, 50% had neuropsychological difficulties and needed rehabilitation and/or psychotherapy for learning or behavior difficulties, and 50% had no difficulties, which may explain the debate about this pathology. Patients with neuropsychological difficulties had a heterogeneous profile with normal intelligence but selective cognitive and/or behavior disorders that may have a long-term impact on their quality of life, particularly those with a right-sided cyst. A neuropsychological evaluation is not always necessary for a cyst discovered incidentally, but early evaluation is essential in patients with academic, learning, or psychological disorders. When assessment shows selective disorders presumably linked to cyst location, surgery may be considered, particularly for convex cysts, as this study revealed more effects in association with cyst shape than with cyst size and significantly poorer performance with a convex cyst.

Disruption of temporally extended self-memory system following traumatic brain injury.

We investigated for the first time the episodic/semantic distinction in remembering the past and imagining the future in traumatic brain injury (TBI), and explored cognitive mechanisms that may underlie their deficits. Fifteen severe TBI patients and 15 control participants performed a battery of neuropsychological tests and a set of verbal fluency tasks designed to assess semantic (personality traits knowledge and general events), and episodic (specific events and details) facets of self-representations according to three time periods (remote/retrograde past, recent/anterograde past, future). Compared to controls, TBI patients showed deficits in both semantic and episodic self-representations, regardless of the time period, and controlling for basic cognitive functions. By contrast, a subjective evaluation of self-concept measuring the degree of certitude and the valence of self did not differ between patients and controls. The deficits were mainly predicted by altered executive function (i.e., updating) for past periods, as well as by general semantic and feature binding in working memory for the future period, independently of the injury characteristics. For controls, only episodic self-representation for each time period was mediated by executive or working memory functions, while semantic self-representation was mediated by the certitude of the self. This study highlights the dual role of semantic and episodic representations in temporally extended self, and shows the global disruption of self-representations across extended time in severe TBI. This encourages the extension of past and future thinking research to TBI populations to provide important insights into the nature and origin of these deficits and their role in recovery and to suggest future lines of research on rehabilitation procedures.

[What about the mental time travel and age-related effects?]. / Quid du voyage mental dans le temps subjectif et effets de l'âge ?

According to Tulving, episodic memory allows humans to travel mentally through subjective time into either the past or the future, this ability being at the origin of adaptation, organization and planning of future behavior. The main aim of this review is to present a state of art of episodic mental time travel and a lifespan perspective from children to elderly people. We examine the numerous similarities between remembering the past and envisioning the future which have been highlighted in cognitive, neuroimaging, and neuropsychological studies. We also present studies that have given evidence that remembering the past and imagining the future differ somewhat. We focus on demonstrating that hippocampal dysfunction is associated with disturbances in the recall of episodic autobiographical details in past memories, but also in the imagining of episodic detailed future events. More specifically, we discuss that the future seems to involve higher semantic processes mediated by the inferior frontal and lateral temporal gyri. We propose that the study of mental travel in personal time could be undertaken in line with the distinction between the memory of (episodic) experiences and (semantic) personal knowledge of one's life, which constitutes a major part of the self and constraints what we have been, what we are now, and what we might yet become.