Ganser Symptoms in a Case of Frontal-Temporal Lobe Dementia: Is There a Common Neural Substrate?

Abstract

Neuropsychological testing was completed in a patient who showed cognitive decline of mental functions, unusual answers to questions, and other characteristics of what has typically been described in the literature as the "Ganser Syndrome." Clear evidence of malingering on a memory test seemed to confirm that this patient was exaggerating deficits for psychiatric reasons or secondary gain, yet the patient showed evidence of mild organic impairment on MRI and continued to deteriorate in cognitive functions and basic self-care. Although an initial SPECT scan had suggested a pattern inconsistent with dementia, a second scan showed frontal-temporal perfusion deficits. Based on this scan and the clinical picture of progressive deterioration, a diagnosis of frontal-temporal lobe dementia was made. This case illustrates that the seemingly deliberate selection of incorrect responses may occur in the early stages of an organic dementia, and that a diagnosis of frontal-temporal lobe dementia should be considered in cases where symptoms appear to be psychiatric or nonorganic. The case further raises the question of whether the reported symptoms of Ganser Syndrome may be accounted for by frontal-temporal lobe dysfunction, since there appears to be some overlap between symptoms of Ganser Syndrome and frontal-temporal lobe dementia. It is also important to note that many reported cases of Ganser Syndrome had a history of head injury.

Towards Solving the Riddle of Forgetting in Functional Amnesia: Recent Advances and Current Opinions

“…A minority of cases of so-labeled functional amnesias may represent early stages of particular neurodegenerative forms of amnesia with early age of onset, where the morphological changes initially might escape capturing by conventional structural brain investigations, but may declare themselves afterward (Ladowsky-Brooks and Fischer, 2003). There are reports in the literature of conditions that had initially been deemed as functional or hysterical, but subsequently re-classified as due to a general medical condition (Slater and Glithero, 1965).…”

“…This loss of information (Ribot, 1882) could be attributed to the fact that those particular memories were not fully “organized” (Burnham, 1903; Markowitsch, 1992) or consolidated (Haist et al, 2001) at the time of the incident. Loss of information may also occur in patients with functional amnesia, who suffer global intellectual deterioration over time (Markowitsch, 1992; Ladowsky-Brooks and Fischer, 2003). Porter and Landfield (1998) underlined the connection between the stress-related cognitive decline, the potential contribution of glucocorticoids to accelerated aging, the fronto-temporal dysfunction, and the later development of dementia.…”

Ganser Symptoms in a Chinese Speaking Corticobasal Syndrome (CBS) Patient

“…3 However, Ganser syndrome also has been described in varieties of organic brain diseases, such as traumatic brain injury, alcoholism with Korsakoff's psychosis, neurosyphilis, 3 and most recently, frontotemporal dementia. 4 Neuropsychological characteristics of Ganser symptoms in organic brain syndromes have been described as inconsistent performance plus multiple verbal and visuospatial approximate answers, and suggested that the seemingly deliberate selection of incorrect responses may occur in the early stages of an organic dementia. 4 It has been hypothesised that frontaltemporal lobe dysfunction may contribute to the picture of Ganser syndrome by leading to the malingering impulse.…”

Psychopathologie des Ganser-Syndroms

“…Neben diesem Kernsymptom gelten weitere Symptome als charakteristisch, wie etwa eine fluktuierende Bewusstseinsstörung, pseudoneurologische Phänomene, visuelle oder akustische Pseudohalluzinationen, dissoziative Fugue-Zustände, affektive Störungen in Form einer kindlich-läppischen Stimmungslage, depressive Verstimmtheit, pseudoepileptische Anfälle sowie verschiedene neuropsychologische Störungen wie Gedächtnislücken und Wahrnehmungsstörungen [21,25,47,50]. Zusammenfassend wurde diese Symptomatik auch als "Pseudodemenz" bezeichnet [30].…”

“…Dabei fällt auf, dass häufig keine neurologische oder neuropsychologische Untersuchung erfolgt ist. Die wenigen vorhandenen Befunde deuten dabei auf eine Störung vor allem frontal-exekutiver Funktionen hin [13,23,25,30]. Kaum untersucht ist, inwiefern das "Vorbeiantworten" als Ausdruck einer "nichtaphasischen Kommunikationsstörung" mit weitschweifiger, inkohärenter Sprache und Vernachlässigen von Kontextinformationen zu werten ist, wie sie bei präfrontalen und rechtshemisphärischen Läsionen beschrieben ist [16,22,40].…”