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Previous studies have shown that cognitive impairments in patients with brain tumors are not severe. However, to preserve the postsurgical QOL of patients with brain tumors, it is important to identify “primary” cognitive functions and associated brain regions that are more vulnerable to cognitive impairments following surgery. The objective of this study was to investigate primary cognitive factors affecting not only simple cognitive tasks but also several other cognitive tasks and associated brain regions. Patients with glioma in the left (n=33) and the right (n=21) hemisphere participated in the study. Seven neuropsychological tasks from five cognitive domains were conducted pre- and 6 months postoperation. Factor analyses were conducted to identify “primary” common cognitive functions affecting the task performance in left and right glioma groups. Next, lesion analyses were performed using voxel-based lesion-symptom mapping (VLSM) to identify critical brain regions related to impairments of the primary cognitive functions. Factor analysis revealed two primary cognitive components in each glioma group. The first cognitive component in the left glioma group affected the digit span forward and backward tasks and concept shifting and the letter-digit substitution tasks. VLSM analysis revealed significant regions from the posterior middle temporal gyri to the supramarginal gyrus. The second cognitive component affected verbal memory, and verbal fluency tasks and VLSM analysis indicated two different significant regions, the medial temporal regions and the middle temporal gyrus to the posterior parietal lobes. The first cognitive component in the right glioma group affected positive and negative factor loadings on the task, such that the positive cognitive component affected only the Stroop color-word task. VLSM related to deficits of the Stroop task revealed significant regions in the anterior medial frontal cortex. On the other hand, the negative component affected concept shifting, word fluency, and digit span forward tasks, and VLSM revealed significant regions in the right inferior frontal cortex. It is suggested that primary cognitive functions related to specific brain regions were possibly affected by glioma resection.

Action disorganization syndrome (ADS) is a frontal lobe neuropsychological syndrome characterized by deficits in the performance of familiar sequential tasks such as making a cup of tea. In this study, we examined the performance of familiar sequential tasks by 3 patients with right frontal brain tumours and no other areas of brain damage. When task-irrelevant objects were presented as distractors in addition to the target objects, all patients used the distractors in accordance with the target task. These patients showed few of the sequential and omission errors that had been previously reported in patients with ADS. Although normal participants could suppress the activation of task-irrelevant objects, these patients had difficulty with this process, which would normally be carried out by the right frontal lobe to determine the most suitable action behaviour. The intact left frontal lobe may receive bottom-up activation from the distractors and modify this schema to match the behavioural context. Our findings suggest that patients with only right frontal lobe damage may be characterized more by action disinhibition than by disorganization.

Background. Perseveration has been observed in a number of behavioural contexts, including speaking, writing, and drawing. However, no previous report describes patients who show perseveration only for drawing a human figure.Objective. The present report describes a group of patients who show body awareness-related cognitive impairment during a human figure drawing task, a different presentation from previously described neuropsychological cases.Methods. Participants were 15 patients who had a frontal lobe brain tumour around the insula cortex of the right hemisphere and had subsequently undergone a neurosurgical resective operation. Participants were asked to draw a human figure in both “hands-down” and “hands-up” configurations.Results. Eight of the 15 patients drew a human figure with six fingers during the “hands-up” and the “hands-down” human figure drawing tasks (one patient drew eight fingers). A statistical analysis of potential lesion areas revealed damage to the right anterior frontal insula and operculum in this group of patients relative to the five-finger drawing group.Conclusions. Our findings reveal a newly described neuropsychological phenomenon that could reflect impairment in attention directed towards body representations.