The Italian Journal of Neurological Sciences

, Volume 19, Supplement 6, pp S403–S407 | Cite as

Memory and executive functions in healthy subjects and patients with multiple sclerosis: the role of PET and SPECT

  • C. Pozzilli
  • A. Pisani
  • M. Gherardi
  • S. Cannoni
  • O. Ciccarelli
Cognitive Dysfunction IN MS


Despite extensive research, the precise role of different brain areas in modulating attentional and mnemonic processes is still controversial. Using positron emission tomography (PET) or single photon emission computed tomography (SPECT), we can measure changes which are associated with the level of neuronal activity in normal subjects and in patients. We describe the pattern of activation in attentional processes, with respect to three basic components: vigilance, selective attention and attentional processing capacity. Furthermore, we underline the predominant role of frontal and temporal cortices that mediate different activities associated with memory function.

Functional techniques have substantially contributed to a better understanding of the cognitive deficits associated with multiple sclerosis (MS), suggesting that cortical- subcortical disconnection is the most likely cause of the neuropsychological deficits. The difficulties in attempting to attribute specific cognitive abnormalities to focal brain pathology in presence of widespread disease such as MS will probably be attenuated by functional neuroimaging studies.

Key words

Memory Executive functions PET SPECT Multiple sclerosis 


Nonostante le molteplici ricerche, non è ancora ben chiaro il ruolo preciso delle differenti aree cerebrali nei processi mnesici ed attenzionali. L'uso di tecniche funzionali come la tomografia ad emissione di positroni (PET) e la tomografia ad emissione di singoli fotoni (SPECT) ha reso possibile valutare le singole diverse strutture the sono coinvolte in tali processi. In questo lavoro, abbiamo preso in considerazione gli study effettuati mediante PET e SPECT mirati ad approfondire il substrato neuroftsiologico alla base dei processi attenzionali. Per quanto riguarda la memoria, è stato esaminato il ruolo delle diverse aree corticali, con particolare riguardo alla corteccia frontale e temporale. Nell'umbito della sclerosi multipla, gli study funzionali hanno messo in luce l'importanza delle strutture sottocorticali per le funzioni mnesiche ed esecutive, contribuendo a chiarire il ruolo della disconnessione tra strutture corticali e sottocorticali.


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Copyright information

© Springer-Verlag 1998

Authors and Affiliations

  • C. Pozzilli
    • 1
  • A. Pisani
    • 1
  • M. Gherardi
    • 1
  • S. Cannoni
    • 1
  • O. Ciccarelli
    • 1
  1. 1.Department of Neuroslogical SciencesUniversity of RomaRomaItaly

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