Neuropsicologia

L'articolo affronta il tema della organizzazione del Sé della personalità ossessiva. Vie-ne posto in evidenza come il tema del rigore morale, intrinsecamente presente in questo tipo di personalità, copra in realtà una dimensione di profonda insicurezza e di fuga dalla responsabilità di definire il proprio modo di essere al mondo, di connotare gli eventi dal punto di vista soggettivo, di affrontare il tema della scelta e della possibilità di commettere errori. Prigionieri di una visione idealizzata della vita e del mondo il Sé ossessivo rifugge dagli stimoli che determinano incertezza attraverso rimuovendo dal proprio orizzonte la dimensione della vitalità, ancorandosi a una visione statica e perfezionista dell'esistere. Gli stimoli che non sono assimilabili a tale visione diventano oggetto di rimozione, di fallimento della mentalizzazione e di scarica afinalistica attra-verso le compulsioni o i pensieri parassiti. L'angoscia di poter essere " altro " dalla vi-sione idealizzata del Sé comporta un sforzo teso a tenere lontano dalla consapevolezza tutto ciò che a tale visione non corrisponde. La lotta tra Sé ideale e il Sé vitale, temuto e temibile, si rende manifesto attraverso le azioni compulsive e i pensieri " estranei " che stanno lì a ricordare che ciò che si vuol silenziare è un possente motore di energia psichica destinata a manifestarsi in termini di angoscia piuttosto che di gioia di vivere e pienezza di sè.

Moral psychologists argue that moral self associated with self-related psychological processes significantly influences moral functioning including moral affection, cognition, and motivation [1,2]. However, there have not been any previous neuroimaging studies that investigated the modulatory role of self-related processes in moral functioning. In the present study, by conducting psycho-physiological interaction (PPI) and Granger causality analyses of neuroimaging data acquired while subjects were solving moral dilemmas, we examined how default mode network (DMN) regions, which are associated with selfhood-related processes in part, such as self-reflection, self-referencing, self-related emotional and episodic memory processing, the posterior cingulate cortex (PCC) and medial prefrontal cortex (MPFC) in particular [3], interact with and affect activity in other brain regions related to moral functioning.
Subjects: 16 right-handed healthy adults (mean age 28.59 years, SD 3.18 years; 8 females; 8 Koreans, 8 Americans) participated in the experiment. Data acquisition: Functional images were scanned at 3T (GE Signa 750, spiral-in/out sequence, TR = 2s). Respiration and cardiac (pulse oximetry) responses were recorded using a respiratory belt and pulse-ox sensor attached to a finger. The data was initially acquired and used for a cross-cultural social neuroscientific experiment [4]. Experiment: Each subject was requested to solve 22 moral-personal, 18 moral-impersonal and 20 neutral dilemmas during functional scanning sessions [4,5,6] (Fig1). Each trial consisted of a 46-sec decision making and 14-sec inter-trial fixation phases. Data analysis: The acquired images were analyzed using SPM 8 and MATLAB. (1) Pre-processing consisted of physiological noise reduction [7,8], slice time correction, motion correction, co-registration, normalization, and spatial smoothing (Gaussian FWHM = 8mm). Demographic variables (ethnicity, age, gender) were included in the statistical model as covariates. (2) A whole-brain t-test examined which regions were significantly activated under both moral-personal and moral-impersonal conditions compared to the control condition. (3) A PPI analysis was performed based on two seed regions, the PCC (MNI [0, -54, 28]) and MPFC (MNI [0, 54, 12]), to investigate which regions showed significant interaction with these seed regions. (4) Additional Granger causality analysis focusing on a region displaying mixed PPI results was conducted using The MVGC Multivariate Granger Causality Toolbox [9].
Results:
(1) Task Activation: In both conditions, regions associated with the DMN were significantly activated as presented in previous studies [3,4,5] (Fig2). More regions showed significant activity under the moral-personal condition compared to the moral-impersonal condition.
(2) PPI Analysis: Under the moral-personal condition, the dorsolateral prefrontal (DLPFC) and orbitofrontal cortices, cerebellum, brainstem, midbrain, and anterior insula (AI) showed significant positive interaction with both the PCC and MPFC. However, the posterior insula (PI) showed significant negative interaction with both seed regions (Fig3(a/b)). Under the moral-impersonal condition, although the overall result was identical to that under the moral-personal condition, the interaction between the MPFC and DLPFC was insignificant (Fig3(c/d)).
(3) Granger Causality Analysis: Only under the moral-personal condition, was significant Granger causality from the PI to AI and MPFC, MPFC to AI, and AI to PCC found (Fig4). However, no significant causality was discovered under the moral-impersonal condition.
Conclusions: Regions of the DMN that take part in selfhood-related processing significantly interacted with other regions associated with moral functioning in moral judgment consistent with our hypothesis. In addition, the result of the Granger causality analysis indicated that there were significant influences between DMN and morality-related regions.
[1] Blasi, A. (1999), ‘Emotions and Moral Motivation’, Journal for the Theory of Social Behavior, vol. 29, no. 1, pp. 1-19.
[2] Hardy, S.A., Carlo, G. (2005), ‘Identity as a Source of Moral Motivation’, Human Development, vol. 48, no. 4, pp. 232-256.
[3] Buckner, R., Andrews-Hanna, J., Schacter, D. (2008), ‘The Brain’s Default Network: Anatomy, Function, and Relevance to Disease’, Annals of the New York Academy of Sciences, vol. 1124, no. 1, pp.1-38.
[4] Han, H., Glover, G.H., Jeong, C. (2014), ‘Cultural Influences on the Neural Correlate of Moral Decision Making Processes’, Behavioural Brain Research, vol. 259, pp. 215-228.
[5] Greene, J.D., Sommerville, R.B., Nystrom, L.E., Darley, J.M., Cohen, J.D. (2001), ‘An fMRI Investigation of Emotional Engagement in Moral Judgment’, Science, vol. 293, no. 5537, pp. 2105-2108.
[6] Greene, J.D., Nystrom, L.E., Engell, A.D., Darley, J.M., Cohen, J.D. (2004), ‘The Neural Bases of Cognitive Conflict and Control in Moral Judgment’, Neuron, vol. 44, no. 2, pp. 389-400
[7] Glover, G.H., Li, T-Q, Ress, D. (2000), ‘Image-based method for retrospective correction of physiological motion effects in fMRI: RETROICOR’, Magnetic Resonance in Medicine, vol. 44, no. 1, pp. 162-167.
[8] Chang, C., Glover, G.H. (2009), ‘Relationship between respiration, end-tidal CO2, and BOLD signals in resting-state fMRI’, NeuroImage, vol. 47, no. 4, pp. 1381-1393.
[9] Barnett, L., Seth, A.K. (2014), ‘The MVGC multivariate Granger causality toolbox: A new approach to Granger-causal inference’, Journal of Neuroscience Methods, vol. 223, pp. 50-68.

El trabajo busca esclarecer sobre el problema de un hipotético código psico-neural que develaría el enigma de las relaciones entre mente y cerebro. Al inicio, se argumenta que la idea de un código psico-neural constituye uno de los problemas centrales de la neurociencia que se remonta al interaccionismo cartesiano y se inscribe en la tradición epistemológica que aspira a matematizar la naturaleza. Luego se  aborda la cuestión de la existencia de un hipotético código mental o lenguaje del pensamiento, formulada por Fodor. A continuación, se analogan los intentos de hallar un código psico-neurales con el develamiento del código genético y el posterior desciframiento y mapeo del genoma humano. Se concluye sobre el carácter problemático de un código psico-neural universal, debido el carácter elusivo e indeterminado de lo mental.