Grammar improvement following deep brain stimulation of the subthalamic and the pedunculopontine nuclei in advanced Parkinson's disease: A pilot study

Received 2 April 2008; received in revised form 4 December 2008; accepted 6 December 2008.

Abstract

Combined deep brain stimulation of the subthalamic (STN) and pedunculopontine (PPN) nuclei has been recently proposed as surgical treatment of advanced Parkinson's disease. STN stimulation alone has been shown to provide selective improvement of the grammatical aspect of language. We studied five advanced Parkinson's disease patients who underwent combined deep brain stimulation (STN + PPN). Overall cognitive profile did not change. On the contrary, an interesting trend towards reduction of ungrammatical errors (particularly substitution of free and inflectional morphemes) was found when stimulating the STN, and also the PPN, when the STN was switched off. These findings replicate previous observations on the STN, and provide the rationale for further investigation of the role of the PPN in processing linguistic grammar.

Keywords: Deep brain stimulation, Language, Parkinson's disease, Pedunculopontine nucleus, Subthalamic nucleus

a Dipartimento di Patologia e Medicina Sperimentale e Clinica, University of Udine, Udine, Italy

b Dipartimento di Neuroscienze, Tor Vergata University, Rome, Italy

c IRCCS “Santa Lucia”, Rome, Italy

d Neurochirurgia Funzionale e Stereotassica, Ospedale CTO, Rome, Italy

Correspondence to: Present address: Associazione “La Nostra Famiglia” – IRCCS “E. Medea” – Polo Regionale del Friuli Venezia-Giulia, Via Cialdini 29, 33037 Pasian di Prato (UD), Italy. Tel.: +39 0432 693111; fax: +39 0432 693106.

PII: S1353-8020(08)00343-X

doi:10.1016/j.parkreldis.2008.12.003

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