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The Supplementary Motor Area (SMA)-syndrome is a transient disturbance of the ability to initiate voluntary motor and speech actions that will often occur immediately after neurosurgical resections in the dorsal superior frontal gyrus but will typically have disappeared after 3 months. The purpose of the present study was to investigate the extent to which this syndrome is associated with alterations in cognitive control. Five patients who were to different extents affected by the SMA-syndrome after surgery for WHO grade II gliomas in the left hemisphere, were tested with the color word interference (Stroop) test; the Bergen dichotic listening test and for letter and category verbal fluency before surgery, 1–2 days after surgery and approximately 3 months after surgery. Results suggest that the motor symptoms known as the SMA syndrome co-occur with pronounced deficits in cognitive control.

BACKGROUND: During the latest decades the hypothesis that the subjective experience of free will is determined by preconscious activity in the dominant dorsal medial frontal cortex (dMFC) has repeatedly challenged our commonly held concepts of moral responsibility.

AIMS OF THE STUDY: To investigate whether dMFC activity determines the sense of free will and to investigate effects of resections in this area on Quality of life (QoL).

METHODS: A cohort of nine patients affected by transient declines in speech and movement skills after surgery involving the left dMFC answered questions about their postoperative, subjective experiences of volition in relation to symptoms. In eight cases resections were performed as part of glioma surgery and in the ninth case a meningioma adjacent to the dMFC was resected. In addition, a QoL questionnaire was administrated before and after surgery.

RESULTS: None of the patients perceived the transient disabilities related to surgery as associated with a loss or absence of volition. No declines in QoL were detected after surgery. Two QoL domains showed improved function (motor dysfunction and future uncertainty).

CONCLUSIONS:The subjective sense of volition is not contingent on dMFC activity. Surgical resections of this area are not typically associated with declines in QoL.

The negative side effects of neurosurgical resection of the lower third of the primary motorcortex (M1) are often described as relatively mild. However, detailed descriptions of how theseresections affect neurocognitive function, speech, mental health and quality of life (QoL) are sparse. Inthe present study, seven patients with suspected lower-grade glioma (WHO II-III) in the inferior M1were assessed for facial motor function, cognitive function, anxiety and QoL before and after awakesurgical resections. The main finding was that after surgery, six of the seven patients experienced amild facial motor dysfunction, mainly affecting the mouth, tongue and throat. At the group level,we were also able to observe a significant postoperative decline in maximum verbal speed, whereasno negative effects on measures of word production (i.e., verbal fluency) were seen. Self-reportedQoL data suggest that some patients experienced increased social isolation postoperatively but donot lend support to the interpretation that this was caused by direct neurological side effects of thesurgery. The results appear to support the general notion that awake surgery in the lower M1 canbe performed safely and with postoperative deficits that are most often perceived by the patient astolerable.

After resective glioma surgery in the Supplementary Motor Area (SMA), patients often experience a transient disturbance of the ability to initiate speech and voluntary motor actions, known as the SMA syndrome (SMAS). It has been proposed that enhanced interhemispheric functional connectivity (FC) within the sensorimotor system may serve as a potential mechanism for recovery, enabling the non-resected SMA to assume the function of the resected region. The purpose of the present study was to investigate the extent to which changes in FC can be observed in patients after resolution of the SMAS.

Eight patients underwent resection of left SMA due to suspected gliomas, resulting in various levels of the SMA syndrome. Resting-state functional MR images were acquired prior to the surgery and after resolution of the syndrome.

At the group level we found an increased connectivity between the unaffected (right) SMA and the primary motor cortex on the same side following surgery. However, no significant increase in interhemispheric connectivity was observed.

These findings challenge the prevailing notion that increased interhemispheric FC serves as the only mechanism underlying recovery from SMA syndrome and suggest the presence of one or more alternative mechanisms.