Tópico: [em inglês] Diversidade neural e interpretação de imageamento cerebral por RM

[Buckaroo Banzai]

[...] Moriguchi et al. (2005) measured task-related brain activity while Japanese and American participants observed fearful facial expressions. The Japanese participants demonstrated more task-related activity in the right inferior frontal gyrus, pre-motor cortex, and left insula, whereas the American participants demonstrated more task-related activity in the posterior cingulate, supplementary motor cortex, and amygdala. The authors concluded that “Americans respond to fearful faces in a more direct, emotional way, whereas Japanese do not attach an emotional valence to the faces.”

Hugdahl et al. (2006) measured task-related activity while male and female participants were performing equally well on a mental rotation task (using Shepard & Metzler, 1971, stimuli). The male participants demonstrated more task-related activity in parietal areas, whereas the female participants demonstrated more task-related activity in inferior frontal regions. The authors concluded that “males may be biased toward a coordinate processing approach, and females biased toward a serial, categorical processing approach.”

When mothers viewed photos of their own children, task-related activity in the amygdala and insula was interpreted as “reflecting the intense attachment, vigilant protectiveness, and empathy that characterize normal maternal attachment” (Leibenluft et al., 2004). When boyfriends listened to sentences such as “my girlfriend gave a gorgeous birthday present to her ex-boyfriend,” task-related activity in the amygdala and insula was interpreted as identifying the “brain regions involved in sexual/aggressive behavior” (Takahashi et al., 2006).

When college-aged participants successfully retrieved episodic memories, task-related activity in frontal regions was considered a sign of higher-order reasoning; when participants of the modal age of APS members successfully retrieved episodic memories, task-related activity in frontal regions was considered “compensation” (Aine et al., 2006). From reading such brain-imaging studies, one would think that amateur psychoanalysts, rather than card-carrying neuroscientists, were driving the interpretations. For my own ride, I’d like to have social psychologists in the passenger seat, bringing along their decades of research on the unfortunate effects of stereotyping, bias, and prejudice.

For example, group comparisons in many functional brain-imaging studies illustrate quite vividly Miller et al.’s (1991) thesis, drawn from behavioral and social psychological research: Explanations for differences between prototypic and nonprototypic groups use the former to explain the latter. Thus, in brain-imaging studies, nonprototypic groups are described as demonstrating more versus less task-related activity — where more and less are always in reference to the prototypic group.

Rather than being appreciated as functional adaptations — as when blind participants activate visual cortex while reading braille (Burton et al., 2002) and Deaf participants activate auditory cortex while perceiving motion (Fine et al., 2005) — levels of activation are often judged in Goldilocks fashion (too much, too little, just right), and regions of activation are often interpreted as if they were Zodiac signs.

As we explore the neural underpinnings of tasks as diverse as grocery shopping (Braeutigam et al., 2004) and tickling (Blakemore et al., 2000), and we recruit participants who are also diverse, let’s consider the possibility of diversity in neural structure and function. And let’s do so without biased inferences or stereotypic interpretations.


[APS President Morton Ann Gernsbacher, University of Wisconsin-Madison]

http://www.psychologicalscience.org/observer/getArticle.cfm?id=2134

[rcms]

São estudos como este que permitem que possamos compreender a estrutura/ comportamento cerebral. Não gosto muito de fMRI, já que não se encontra um em cada esquina para utilização ($$$).

[rcms]

3.2. Emotional processing
Weiskopf et al. (Weiskopf et al. [13]) used fMRI-BCI to study the effect of volitional control of anterior cingulated cortex (ACC) on emotional processing. From previous anatomical and functional studies two major subdivisions of the ACC are distinguished, which subserve two distinct types of functions. The dorsal ACC is called the “cognitive division” (ACcd) and the rostral-ventral “affective” division (ACad). Due to its involvement in different functional networks, physiological self-regulation was applied to study cognitive and emotional parameters, for example, emotional valence and arousal, dependent on the differential activation of the two subdivisions. In this study, two continuously updated curves were presented to the subject depicting BOLD activity in ACcd and ACad. During blocks of 60-second duration, subjects were instructed to move both curves upwards (alternating 60 seconds rest and 60 seconds up-regulation). The subject was instructed to use his own strategy for voluntary BOLD regulation. The subject reported that he used the imagery of winter landscapes, engaging in snowboarding and social interactions during up-regulation, and attending to the feedback curve without performing any specific imagery during the rest blocks. An improved control of the rostral-ventral affective subdivision was observed during training. Subsequent testing of the affective state using self-assessment Manikin (SAM) (Bradley and Lang [31]) showed an increase in valence and arousal during the up-regulation of BOLD in the ACad only.

In a recent study (Caria et al. [32], Figure 4), we investigated whether healthy subjects could voluntarily gain control over right anterior insular activity. Subjects were provided with continuously updated information of the target ROI's level of activation by the thermometer feedback. All participants were able to successfully regulate BOLD—magnitude in the right anterior insular cortex within three sessions of four blocks each. Training resulted in a significantly increased activation cluster in the anterior portion of the right insula across sessions. An increased activity was also found in the left anterior insula but the percent signal change was lower than in the target ROI. Two different control conditions intended to assess the effects of nonspecific feedback and mental imagery demonstrated that the training effect was not due to unspecific activations or non-feedback-guided strategies. Both control groups showed no enhanced activation across the sessions which confirmed our main hypothesis that rtfMRI feedback is area specific. The increased activity in the right anterior insula during training demonstrates that the effects observed are functionally specific and self-regulation of right anterior insula only is achievable. This is the first group study demonstrating that volitional control of an emotional area can be learned by training with an fMRI-BCI. We are presently conducting further studies to understand the behavioral effects of volitional control of insula.

Integra:
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2233807

[rcms]

Uma aplicação direta deste tipo de mensuração e identificação de comportamento cerebral é a possibilidade de projetar softwares que analisem o grau de frustração/satisfação do user e o analista ao estudar os dados obtidos pode identificar gaps de interface, falhas de usabilidade etc.. Propiciando ao projetista evoluir consistentemente o sistema inicial desenvolvido.
Observe a aplicação de biofeedback aqui: The subject was instructed to use his own strategy for voluntary BOLD regulation. .

Imagine a medição do nivel de frustração de alguns usuários Windows durante a ocorrencia de erros. Gostaria de saber se a microsoft analisa aquela quantidade de relatorio de erros que ela deve receber diariamente. =P