Dissociative Amnesia: Remembrances Under Cover.

The existence or questionability of "repressed memories" can be discussed as being a matter of definition. It seems, however, far-fetched to consider all "lost" memories as caused by encoding problems, brain damage, forgetfulness, failure to disclose events, and so on. We argue that dissociative amnesia (DA) (or "psychogenic amnesia," or "functional amnesia," or, as we favor to call it, "mnestic block syndrome") is caused by psychic alterations, but ultimately they can be traced to changes in the physiology of the brain, as we are of the opinion that all memory processes-positive or negative-alter brain functions, sometimes more permanently, sometimes transiently.

The need for a unified framework: How Tulving's framework of memory systems, memory processes, and the SPI-model can guide and sharpen the understanding of déjà vu and involuntary autobiographical memories and add to conceptual clarity.

Barzykowski and Moulin link déjà vu and involuntary autobiographical memories to the process of retrieval. They make no reference to Tulving's SPI-model. In this, it is proposed that information is acquired serially (S), stored in parallel (P), and retrieved independently (I).

Behavioral, neurological, and psychiatric frailty of autobiographical memory.

Autobiographical-episodic memory is considered to be the most complex of the five long-term memory systems. It is autonoetic, which means, self-reflective, relies on emotional colorization, and needs the features of place and time; it allows mental time traveling. Compared to the other four long-term memory systems-procedural memory, priming, perceptual, and semantic memory-it develops the latest in phylogeny and ontogeny, and is the most vulnerable of the five systems, being easily impaired by brain damage and psychiatric disorders.

Quo vadis 'episodic memory'? - Past, present, and perspective.

The term 'episodic memory' was coined by Endel Tulving, who also created a classification in several memory systems. This classification is presented, and it is described which predecessors existed for the partition of memory into systems. The 'episodic memory system' is discussed as being in general equivalent with the 'episodic-autobiographical memory system'.

Stress- and trauma-related blockade of episodic-autobiographical memory processing.

Memory disorders without a direct neural substrate still belong to the riddles in neuroscience. Although they were for a while dissociated from research and clinical arenas, risking becoming forgotten diseases, they sparked novel interests, paralleling the refinements in functional neuroimaging and neuropsychology. Although Endel Tulving has not fully embarked himself on exploring this field, he had published at least one article on functional amnesia (Schacter et al.

Episodic memory is emotionally laden memory, requiring amygdala involvement.

The memory impairment of neurological and psychiatric patients is seen as occurring mainly in the autobiographical-episodic memory domain and this is considered to depend on limbic structures such as the amygdala or the septal nuclei. Especially the amygdala is a hub for giving an emotional flavor to personal memories. Bastin et al.

Is self-report sleepiness associated with cognitive performance in temporal lobe epilepsy?

Objectives: Sleepiness and cognitive impairment are common symptoms observed in patients with epilepsy. We investigate whether self-reported sleepiness is associated with cognitive performance in patients with refractory mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). Seventy-one consecutive patients with MTLE-HS were evaluated with the Stanford Sleepiness Scale (SSS) before neuropsychological evaluation.

Neural correlates of free recall of "famous events" in a "hypermnestic" individual as compared to an age- and education-matched reference group.

Background: Memory performance of an individual (within the age range: 50-55 years old) showing superior memory abilities (protagonist PR) was compared to an age- and education-matched reference group in a historical facts ("famous events") retrieval task.

Results: Contrasting task versus baseline performance both PR and the reference group showed fMRI activation patterns in parietal and occipital brain regions. The reference group additionally demonstrated activation patterns in cingulate gyrus, whereas PR showed additional widespread activation patterns comprising frontal and cerebellar brain regions.

Psychological causes of autobiographical amnesia: A study of 28 cases.

Autobiographical amnesia is found in patients with focal or diffuse brain damage ("organic amnesia"), but also without overt brain damage (at least when measured with conventional brain imaging methods). This last condition is usually named dissociative amnesia at present, and was originally described as hysteria. Classically and traditionally, dissociative amnesia is seen as a disorder that causes retrograde amnesia in the autobiographical domain in the aftermath of incidents of major psychological stress or trauma.

Decline in word-finding: The objective cognitive finding most relevant to patients after mesial temporal lobe epilepsy surgery.

Purpose: The purpose of this study was to investigate the following: i) the objective impairment in neuropsychological tests that were associated with the subjective perception of cognitive function decline in Brazilian patients who underwent mesial temporal lobe epilepsy (MTLE) surgery and ii) the predictive variables for those impaired objective neuropsychological tests.

Methods: Forty-eight adults with MTLE (27 right HS and 23 male) were divided according to their perception of changes (Decline or No-decline) of cognitive function domain of the QOLIE-31 questionnaire applied before and 1year after the ATL. The mean (SD) of changes in the raw score difference of the neuropsychological tests before and after the ATL was compared between Decline and No-decline groups.

Dissociative amnesia.

Dissociative amnesia is one of the most enigmatic and controversial psychiatric disorders. In the past two decades, interest in the understanding of its pathophysiology has surged. In this report, we review new data about the epidemiology, neurobiology, and neuroimaging of dissociative amnesia and show how advances in memory research and neurobiology of dissociation inform proposed pathogenetic models of the disorder.

Validation of diagnostic tests for depressive disorder in drug-resistant mesial temporal lobe epilepsy.

Purpose: This study aimed to evaluate the diagnostic accuracy of the Hamilton Rating Scale for Depression (HRSD), the Beck Depression Inventory (BDI), the Hospital Anxiety and Depression Scale (HADS), and the Hospital Anxiety and Depression Scale-Depression subscale (HADS-D) as diagnostic tests for depressive disorder in drug-resistant mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS).

Methods: One hundred three patients with drug-resistant MTLE-HS were enrolled. All patients underwent a neurological examination, interictal and ictal video-electroencephalogram (V-EEG) analyses, and magnetic resonance imaging (MRI).

The nature of the semantic/episodic memory distinction: A missing piece of the "working through" process.

The relations between the semantic and episodic-autobiographical memory systems are more complex than described in the target article. We argue that understanding the noetic/autonoetic distinction provides critical insights into the foundation of the delineation between the two memory systems. Clarity with respect to the criteria for classification of these two systems, and the evolving conceptualization of episodic memory, can further neuroscientifically informed therapeutic approaches.

Impairments in Episodic-Autobiographical Memory and Emotional and Social Information Processing in CADASIL during Mid-Adulthood.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) - is the most common genetic source of vascular dementia in adults, being caused by a mutation in NOTCH3 gene. Spontaneous de novo mutations may occur, but their frequency is largely unknown. Ischemic strokes and cognitive impairments are the most frequent manifestations, but seizures affect up to 10% of the patients.

A Bayesian latent group analysis for detecting poor effort in a sample of cognitively impaired patients.

Using a Bayesian latent group analysis in a simulation design, we recently showed a high diagnostic accuracy when assessing effort in the context of malingered memory deficits. We here further evaluate our Bayesian model in a sample of cognitively impaired patients. The main analysis showed both high sensitivity and specificity, thus corroborating a high diagnostic accuracy of the model.

Deficient symbol processing in Alzheimer disease.

Symbols and signs have been suggested to improve the orientation of patients suffering from Alzheimer disease (AD). However, there are hardly any studies that confirm whether AD patients benefit from signs or symbols and which symbol characteristics might improve or impede their symbol comprehension. To address these issues, 30 AD patients and 30 matched healthy controls performed a symbol processing task (SPT) with 4 different item categories.

The perception of facial emotions--cues from the left amygdaloid complex.

The history and the behavioral profile of 2 patients with brain abnormalities in the region of the left amygdaloidal complex might suggest that the dysfunction of the neural pathways related to the left amygdala has to occur at an early developmental stage to result in impaired emotional judgments of facial expressions. This is in line with the hypothesis that emotional information processing is based on a distributed neural network which, during ontogenesis, gradually expands from the amygdala and the amygdaloidal complex to further components of the limbic system.

Anterior and posterior subareas of the dorsolateral frontal cortex in socially relevant decisions based on masked affect expressions.

Socially-relevant decisions are based on clearly recognizable but also not consciously accessible affective stimuli. We studied the role of the dorsolateral frontal cortex (DLFC) in decision-making on masked affect expressions using functional magnetic resonance imaging. Our paradigm permitted us to capture brain activity during a pre-decision phase when the subjects viewed emotional expressions below the threshold of subjective awareness, and during the decision phase, which was based on verbal descriptions as the choice criterion.