Where is the action? Action sentence processing in Parkinson's disease.

Department of Neurology, Medical College of Wisconsin. Electronic address: .
Neuropsychologia (Impact Factor: 3.45). 04/2013; DOI: 10.1016/j.neuropsychologia.2013.04.008
Source: PubMed

ABSTRACT According to an influential view of conceptual representation, action concepts are understood through motoric simulations, involving motor networks of the brain. A stronger version of this embodied account suggests that even figurative uses of action words (e.g., grasping the concept) are understood through motoric simulations. We investigated these claims by assessing whether Parkinson's disease (PD), a disorder affecting the motor system, is associated with selective deficits in comprehending action-related sentences. Twenty PD patients and 21 age-matched controls performed a sentence comprehension task, where sentences belonged to one of four conditions: literal action, non-idiomatic metaphoric action, idiomatic action, and abstract. The same verbs (referring to hand/arm actions) were used in the three action-related conditions. Patients, but not controls, were slower to respond to literal and idiomatic action than to abstract sentences. These results indicate that sensory-motor systems play a functional role in semantic processing, including processing of figurative action language.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Within the last decade, the neurobiology of action processing has moved from an obscure topic of specialist interest to one of the most popular themes in modern neuroscience. However, the wealth of literature and the diversity of approaches and theoretical models can make the field complex and, at times, bewildering. This review presents the main currents of research, examining their theoretical underpinnings in an interdisciplinary context. The presence of specific deficits in verb and action processing has been documented in a wide range of neurodegenerative diseases, including parkinsonian syndromes and motor neuron disease. Interestingly, most of these disorders affect the motor system, suggesting a systematic relationship between motor functions and their cognitive and linguistic representations. Action processing has been explored with a whole spectrum of methodologies, from neuroimaging to transcranial and intracranial stimulation. The findings have been integrated with other influential concepts and theories, including mirror neurons and embodied cognition. Converging evidence from patient and imaging studies links the concepts of actions and their processing with the execution of actions through the motor system. The theory of embodied cognition remains influential as well as controversial. However, the points of criticism have changed, reflecting recent paradigm shifts.
    Current opinion in neurology 10/2013; · 5.73 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Patients affected by Parkinson's disease (PD) can provide crucial information about the involvement of the motor system and prefrontal cortex in processing idioms including action verbs, since dopamine modulates the activity of these structures, and, consequently, different levels of this neurotransmitter can induce different cognitive impairments. In order to investigate the ability to process ambiguous idioms containing an action verb in patients, we asked 15 PD patients, in both OFF- and ON-phases, and 15 healthy matched participants to judge the plausibility of literal and idiomatic sentences, each presented at a self-paced rate. Patients in OFF-phase were faster in reading idiomatic than literal sentences, supporting the view that the motor system is not involved in online idiom processing. However, patients during OFF-phase were impaired in judging the plausibility of idiomatic ambiguous sentences, possibly due to the reduction of dopamine in prefrontal regions. The involvement of the motor system was evident in the ON-phase for literal sentences, suggesting that motor activation is strictly dependent on the context.
    Cognitive Neuropsychology 01/2014; · 1.52 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We explored implicit motor simulation processes in Parkinson's Disease (PD) patients with ON-OFF subthalamic deep brain stimulation (DBS) of the sub-thalamic nucleus (STN). Participants made lexical decisions about hand action-related verbs, abstract verbs, and pseudowords presented either within a positive (e.g., "Do …") or a negative (e.g., "Don't …") sentence context. Healthy controls showed significantly slower responses for hand-action verbs (vs. abstract verbs) in the negative (vs. positive) context, which suggests that negative contexts may suppress motor simulation or preparation processes. The STN-DBS improves cortical motor functions, thus patients are expected to perform at the same level as unimpaired subjects in the ON condition. By contrast, the 50% reduced DBS is expected to result in a reduced activation for motor information, which in turn might cause a reduced, if not absent, context modulation. PD patients exhibited the same pattern as controls when their DBS was at 100% ON; however, reducing the DBS to 50% had a deleterious outcome on the positive faster than negative context effect, suggesting that the altered inhibition mechanism in PD could be responsible for the missed effect. In addition, our results confirm the view that implicit motor simulation mechanisms behind action-related verb processing are flexible and context-dependent.
    Brain Research 06/2014; · 2.83 Impact Factor


Available from
Jun 4, 2014