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79. Neural substrate of face conscious perception
Society Proceedings / Clinical Neurophysiology 119 (2008) e99–e164
found in the phonologic dyslexics suggest a more generalized underlying difficulty in central auditory processing. Neuropsychological characterization of subtypes in developmental dyslexia contradicts the idea of the existence of a unique cognitive mechanism damaged in this entity. The linguistic components of evoked related potentials (ERP) provide a functional window to find the underlying dysfunction within a temporal sequence of processing stages related with reading. doi:10.1016/j.clinph.2008.04.094
e119
ERP showed a larger N400 in counterfactual than factual sentences (F (1, 34) = 4.23, MSe = 192; p < .05), in the last word of the sentence that could be a consequence of the additional cognitive effort of processing counterfactual meaning. The tomography solution showed in counterfactual sentences, an extensive brain activation in the anterior and posterior cingulate cortex, as well as the precuneous and the left insula. Finally, the time-frequency analysis of EEG showed more intensive gamma activity at frontal and parietal sites in factual than counterfactual sentences, suggesting more cognitive effort in the latter. doi:10.1016/j.clinph.2008.04.096
79. Neural substrate of face conscious perception—V. Rodrı´guez, R. Thompson, J. Duncan (Cuba) Despite growing evidence about the neural substrate of visual conscious perception there is not a consensus yet on whether it is the activation of frontoparietal areas which are essential for the generation of conscious experience. In this study we explore the neural correlates of perceptual awareness during a face-masking detection task. A four-point scale- was employed allowing participants to rate and to report their subjective visibility. With this task a fMRI study was carried out in 22 normal subjects (ages between 40 and 67 years). The results obtained showed that attending and consciously reporting a face was related with a higher activation of face-processing area FFA; and effect that was higher in the right hemisphere and increased with exposition time. Frontoparietal regions (SMA, DLPC, IFS, IPS) also responded strongly when faces were consciously perceived regardless exposition time. However, this network was also activated when subjects considered that a face could have been presented -even if it was not-; suggesting that activity in these areas is shaped to respond to the stimulus identified as target in the current task context. Even when non conclusive these results support the view that frontoparietal activation is indeed associated with conscious experience. doi:10.1016/j.clinph.2008.04.095
80. Understanding counterfactuals. An ERP study—M. de Vega, M. Urrutia (Spain) Healthy participants listened to short stories describing an initial situation, followed by a factual or a counterfactual event, and a final sentence that was either consistent or inconsistent with the previous text. The ERP time-locked to some critical words showed a larger N400 following counterfactuals. An EEG-based thomographic solution (VARETA) showed in counterfactuals activation in the anterior and posterior cingulate cortex and the left insula. Forty participants were given 160 stories, 40 for each of the possible experimental versions. The stories were given auditorily, except the 6-words critical sentence, which was presented visually word-by-word, and participants had to answer comprehension questions in 30% of the stories. There were 4 different versions for each story. The EEG was recorded from 58 thin electrodes mounted on an electrode cap and amplified using a Medicid-4 system. Three kind of analysis were performed on the EEG signal: event-related potentials (ERP), inverse tomography solution (VARETA), and time-frequency waves (wavelets). The
81. Musicians with absolute pitch: Distinct neural network for pitch labeling?—C. Wu, I.J. Kirk, J.P. Hamm, V. Lim (New Zealand) Investigating the neural substrates of auditory processing of absolute pitch musicians has relevance for understanding the capabilities of the human brain for plasticity. Electroencephalography was used to examine the N1 of auditory-evoked potentials from absolute pitch musicians, non-absolute pitch musicians, and non-musicians during tone labeling tasks with and without presentation of a reference tone. Source localization using low-resolution electromagnetic tomography revealed that when labeling tones without a reference, absolute pitch musicians generated greater activity than non-absolute pitch musicians in the left and right hemisphere. This suggests that when required to label tones without an external reference, absolute pitch musicians have the ability to recruit a greater network than non-absolute pitch musicians or non-musicians. doi:10.1016/j.clinph.2008.04.097
82. Proposal for an integral neuropsychological rehabilitation: Effectiveness of a multimodal model—A. Castillo Rube´n, F.G. Me´ndez (Mexico) In this article we present the neuropsychological rehabilitation PAINT model and its effectiveness for persons with brain damage. Archival data of 20 patients with brain injury, who had been evaluated with the Luria-Nebraska Neuropsychological Battery, the Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Memory Scale, before and after neuropsychological rehabilitation, were analyzed. All the patients underwent a holistic, intensive, multi-factorial, systemized and interdisciplinary rehabilitation program during a mean period of 10.2 months, directed toward the hierarchic rehabilitation of the damaged function and to the stimulation of the functions of all cerebral lobes, through formal tasks and activities of daily life. Analysis of clinically significance improvement indicates a high efficiency of treatment in overall neuropsychological functioning. WAIS subtests results show significant improvement in Picture completion, Arithmetic, Similarities. Luria-Nebraska scales performed significantly better in Visual, Tactile, Memory, Intellectual Processes, and Motor. Wechsler Memory Scale had a better outcome in Orientation, Associated word pairs, Logic memory. The multifactor intervention using the PAINT model for the rehabilitation of brain
found in the phonologic dyslexics suggest a more generalized underlying difficulty in central auditory processing. Neuropsychological characterization of subtypes in developmental dyslexia contradicts the idea of the existence of a unique cognitive mechanism damaged in this entity. The linguistic components of evoked related potentials (ERP) provide a functional window to find the underlying dysfunction within a temporal sequence of processing stages related with reading. doi:10.1016/j.clinph.2008.04.094
e119
ERP showed a larger N400 in counterfactual than factual sentences (F (1, 34) = 4.23, MSe = 192; p < .05), in the last word of the sentence that could be a consequence of the additional cognitive effort of processing counterfactual meaning. The tomography solution showed in counterfactual sentences, an extensive brain activation in the anterior and posterior cingulate cortex, as well as the precuneous and the left insula. Finally, the time-frequency analysis of EEG showed more intensive gamma activity at frontal and parietal sites in factual than counterfactual sentences, suggesting more cognitive effort in the latter. doi:10.1016/j.clinph.2008.04.096
79. Neural substrate of face conscious perception—V. Rodrı´guez, R. Thompson, J. Duncan (Cuba) Despite growing evidence about the neural substrate of visual conscious perception there is not a consensus yet on whether it is the activation of frontoparietal areas which are essential for the generation of conscious experience. In this study we explore the neural correlates of perceptual awareness during a face-masking detection task. A four-point scale- was employed allowing participants to rate and to report their subjective visibility. With this task a fMRI study was carried out in 22 normal subjects (ages between 40 and 67 years). The results obtained showed that attending and consciously reporting a face was related with a higher activation of face-processing area FFA; and effect that was higher in the right hemisphere and increased with exposition time. Frontoparietal regions (SMA, DLPC, IFS, IPS) also responded strongly when faces were consciously perceived regardless exposition time. However, this network was also activated when subjects considered that a face could have been presented -even if it was not-; suggesting that activity in these areas is shaped to respond to the stimulus identified as target in the current task context. Even when non conclusive these results support the view that frontoparietal activation is indeed associated with conscious experience. doi:10.1016/j.clinph.2008.04.095
80. Understanding counterfactuals. An ERP study—M. de Vega, M. Urrutia (Spain) Healthy participants listened to short stories describing an initial situation, followed by a factual or a counterfactual event, and a final sentence that was either consistent or inconsistent with the previous text. The ERP time-locked to some critical words showed a larger N400 following counterfactuals. An EEG-based thomographic solution (VARETA) showed in counterfactuals activation in the anterior and posterior cingulate cortex and the left insula. Forty participants were given 160 stories, 40 for each of the possible experimental versions. The stories were given auditorily, except the 6-words critical sentence, which was presented visually word-by-word, and participants had to answer comprehension questions in 30% of the stories. There were 4 different versions for each story. The EEG was recorded from 58 thin electrodes mounted on an electrode cap and amplified using a Medicid-4 system. Three kind of analysis were performed on the EEG signal: event-related potentials (ERP), inverse tomography solution (VARETA), and time-frequency waves (wavelets). The
81. Musicians with absolute pitch: Distinct neural network for pitch labeling?—C. Wu, I.J. Kirk, J.P. Hamm, V. Lim (New Zealand) Investigating the neural substrates of auditory processing of absolute pitch musicians has relevance for understanding the capabilities of the human brain for plasticity. Electroencephalography was used to examine the N1 of auditory-evoked potentials from absolute pitch musicians, non-absolute pitch musicians, and non-musicians during tone labeling tasks with and without presentation of a reference tone. Source localization using low-resolution electromagnetic tomography revealed that when labeling tones without a reference, absolute pitch musicians generated greater activity than non-absolute pitch musicians in the left and right hemisphere. This suggests that when required to label tones without an external reference, absolute pitch musicians have the ability to recruit a greater network than non-absolute pitch musicians or non-musicians. doi:10.1016/j.clinph.2008.04.097
82. Proposal for an integral neuropsychological rehabilitation: Effectiveness of a multimodal model—A. Castillo Rube´n, F.G. Me´ndez (Mexico) In this article we present the neuropsychological rehabilitation PAINT model and its effectiveness for persons with brain damage. Archival data of 20 patients with brain injury, who had been evaluated with the Luria-Nebraska Neuropsychological Battery, the Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Memory Scale, before and after neuropsychological rehabilitation, were analyzed. All the patients underwent a holistic, intensive, multi-factorial, systemized and interdisciplinary rehabilitation program during a mean period of 10.2 months, directed toward the hierarchic rehabilitation of the damaged function and to the stimulation of the functions of all cerebral lobes, through formal tasks and activities of daily life. Analysis of clinically significance improvement indicates a high efficiency of treatment in overall neuropsychological functioning. WAIS subtests results show significant improvement in Picture completion, Arithmetic, Similarities. Luria-Nebraska scales performed significantly better in Visual, Tactile, Memory, Intellectual Processes, and Motor. Wechsler Memory Scale had a better outcome in Orientation, Associated word pairs, Logic memory. The multifactor intervention using the PAINT model for the rehabilitation of brain