Perception of pain in the minimally conscious state with PET activation: an observational study

Boly, Mélanie; Faymonville, Marie-Élisabeth; Schnakers, Caroline; Peigneux, Philippe; Lambermont, Bernard; Phillips, Christophe; Lancellotti, Patrizio; Luxen, André; Lamy, Maurice; Moonen, Gustave; Maquet, Pierre; Laureys, Steven

doi:10.1016/s1474-4422(08)70219-9

Cited by 342 publications

(229 citation statements)

References 46 publications

Supporting

Mentioning

212

Contrasting

Unclassified

Order By: Relevance

“…Since its formal definition nearly 10 years ago [9], a number of authors have questioned the usefulness of differentiating vegetative/unresponsive from minimally responsive patients considering both patient groups as hopelessly brain damaged [24]. Recent studies have demonstrated that it is important to disentangle both clinical entities as functional neuroimaging have shown differences in residual cerebral processing and hence, conscious perception (e.g., [20,[25][26][27]), as well as differences in outcome (e.g., [28,29]). …”

Section: Time For a New Nosology Of Disorders Of Consciousness?mentioning

confidence: 99%

From unresponsive wakefulness to minimally conscious PLUS and functional locked-in syndromes: recent advances in our understanding of disorders of consciousness

et al. 2011

Self Cite

View full text Add to dashboard Cite

Functional neuroimaging and electrophysiology studies are changing our understanding of patients with coma and related states. Some severely brain damaged patients may show residual cortical processing in the absence of behavioural signs of consciousness. Given these new findings, the diagnostic errors and their potential effects on treatment as well as concerns regarding the negative associations intrinsic to the term vegetative state, the European Task Force on Disorders of Consciousness has recently proposed the more neutral and descriptive term unresponsive wakefulness syndrome. When vegetative/unresponsive patients show minimal signs of consciousness but are unable to reliably communicate the term minimally responsive or minimally conscious state (MCS) is used. MCS was recently subcategorized based on the complexity of patients' behaviours: MCS? describes highlevel behavioural responses (i.e., command following, intelligible verbalizations or non-functional communication) and MCS-describes low-level behavioural responses (i.e., visual pursuit, localization of noxious stimulation or contingent behaviour such as appropriate smiling or crying to emotional stimuli). Finally, patients who show nonbehavioural evidence of consciousness or communication only measurable via para-clinical testing (i.e., functional MRI, positron emission tomography, EEG or evoked potentials) can be considered to be in a functional locked-in syndrome. An improved assessment of brain function in coma and related states is not only changing nosology and medical care but also offers a better-documented diagnosis and prognosis and helps to further identify the neural correlates of human consciousness.

show abstract

Section: Time For a New Nosology Of Disorders Of Consciousness?mentioning

confidence: 99%

From unresponsive wakefulness to minimally conscious PLUS and functional locked-in syndromes: recent advances in our understanding of disorders of consciousness

et al. 2011

Self Cite

View full text Add to dashboard Cite

show abstract

“…These "awareness areas" anatomically overlap with the brain's default network areas (44), which might also be involved in self-awareness (44,45). In these persistent vegetative state patients, pain stimuli activate the thalamus and S1, but this primary cortex is functionally disconnected from the secondary somatosensory cortex as well as from the abovementioned awareness areas (43,46,47). Similarly, in these patients activation induced by auditory stimulation is restricted to the primary auditory cortex (A1) bilaterally, without functional connectivity to the inferior parietal cortex, the hippocampus, the anterior cingulate, and the posterior cingulate (43,48,49).…”

mentioning

confidence: 99%

Phantom percepts: Tinnitus and pain as persisting aversive memory networks

Ridder¹,

Elgoyhen

Romo

et al. 2011

Proc. Natl. Acad. Sci. U.S.A.

525

468

View full text Add to dashboard Cite

Phantom perception refers to the conscious awareness of a percept in the absence of an external stimulus. On the basis of basic neuroscience on perception and clinical research in phantom pain and phantom sound, we propose a working model for their origin. Sensory deafferentation results in high-frequency, gamma band, synchronized neuronal activity in the sensory cortex. This activity becomes a conscious percept only if it is connected to larger coactivated "(self-)awareness" and "salience" brain networks. Through the involvement of learning mechanisms, the phantom percept becomes associated to distress, which in turn is reflected by a simultaneously coactivated nonspecific distress network consisting of the anterior cingulate cortex, anterior insula, and amygdala. Memory mechanisms play a role in the persistence of the awareness of the phantom percept, as well as in the reinforcement of the associated distress. Thus, different dynamic overlapping brain networks should be considered as targets for the treatment of this disorder.A fundamental concept in psychology and philosophy of the mind is the notion of perception: The act of interpreting and organizing a sensory stimulus to produce a meaningful experience of the world and of oneself. A stimulus produces an effect on the different sensory receptors, inducing sensation. Further processing of this sensory stimulation generates an internal representation of the outer and inner world called a percept. Since the first days of psychology, two challenging questions have existed: How is sensory information encoded and, in particular, how is this represented information transformed into the individual awareness of a conscious percept (1)? Our understanding of sensory encoding, perception, and consciousness is challenged with a further degree of complexity in the case of phantom perception, the conscious awareness of a percept in the absence of an external stimulus. Deciphering the underlying neural correlates of phantom perception is a scientific endeavor that will aid in understanding the active processes of selecting, organizing, and interpreting information, which ultimately lead to the formation of a conscious percept within the brain.Although some cases of phantom percepts have been described for the visual, olfactory, and gustatory systems, the vast majority of sensory phantoms are those present in the somatosensory (phantom limb perception/phantom limb pain and neuropathic pain) (2) and auditory (tinnitus) (3) modalities. Upfront we are challenged with the following questions: In the absence of an external sensory stimulus, where and how in the brain is the conscious percept generated? In addition, are the neural substrates underlying the generation of a conscious phantom percept similar for the auditory and somatosensory modalities? If so, can we advance in our understanding and treatment of tinnitus on the basis of what is known for phantom limb and phantom pain perception and vice versa? Here, we address these questions and propose a working model of how pha...

show abstract

“…6 It is important to identify, as early as possible, minimal signs of consciousness in non-communicative patients after brain injury. Patients in minimally conscious state have preserved emotional processing, including pain perception, 7 needing appropriate clinical and analgaesic management.…”

Section: *Massimomentioning

confidence: 99%