Mentalizing Mentalizing

I am the opposite of you
You battle your mean spirit
I'm suffering through my own
You answer to no one
I don’t know what that’s like
I honestly don’t know what that’s like

-Throwing Muses, Mercury

I'm really trying to imagine what is in the minds of social psychologists who design fMRI studies like this one, but I can't seem to do it. Perhaps I should follow their advice (Jenkins et al., 2008):

Importantly, introspection can only provide insight about another's feelings, beliefs, and preferences to the extent that one's own mind serves as a reasonable proxy for that of the other person. If two people tend to experience very different mental states in the same situations, neither would be well advised to attempt to mentalize about the other on the basis of her own introspection. Thus, the strategy of using one's own mental states as a basis for understanding those of others should be limited to situations in which one can assume that another person generally thinks and feels similarly to oneself. Perceivers may less readily use their own mental states as a guide to the thoughts and feelings of people perceived to be substantially dissimilar from self.

I must be substantially dissimilar from a social psychologist...



What is mentalizing?¹

Mentalizing refers to our ability to read the mental states of other agents and engages many neural processes. The brain's mirror system allows us to share the emotions of others. Through perspective taking, we can infer what a person currently believes about the world given their point of view.

It's an extremely complicated aspect of social cognition and as such is not easily reducible to its putative components and processes -- which, according to Wikipedia, include schemas, representations, regulation, memory, attention, accessibility, salience, priming, etc. In fact, some neurophilosophers maintain that the neuroscientific study of beliefs, desires, etc. is hopelessly naïve and predicated on erroneous folk psychological notions. But I digress.

What did the current study do? The authors proposed to use the technique of repetition suppression (the mechanisms of which are poorly understood even in studies examining object processing in the lateral occipital complex) to determine whether mentalizing about "similar others" draws on the same neural resources as introspecting about oneself, in contrast to mentalizing about "dissimilar others." Thus, the experiment was constructed as a priming study of sorts, where thoughts about oneself were preceded by either thoughts of similar others (primed), or thoughts of dissimilar others (unprimed). Reductions in neural activity for the primed condition -- repetition suppression -- would suggest that the participants were drawing on the same "self-evaluation" sort of neural regions to guess the mental states of those deemed similar to themselves.

So how were "the others" classified relative to the study participants? After the scanning session, the subjects (13 Boston area students)

...answered two questions about their own sociopolitical attitudes in random order ("How politically liberal or conservative are you?" and "How socially liberal or conservative are you?") by using a 7-point scale (1 = very liberal, 4 = neither liberal nor conservative, and 7 = very conservative).

The mean was 3.03, so the group was slightly liberal but fairly middle of the road. And how did the researchers classify them? Why, as liberals! Gah!

OK, let's look at "the others" and the task.

Participants were told that the experiment investigated the ability to make inferences about others on the basis of minimal information. Before scanning, participants read a short paragraph about each of two unfamiliar target individuals depicted by face photographs. Following Mitchell et al. (2006), one target was described as a college student in the Northeast who maintained liberal social and political attitudes similar to those of our typical student participant. In contrast, the other target was described as a conservative, fundamentalist Republican attending a large university in the Midwest (i.e., as fairly dissimilar from our typical participant)....

During scanning, participants performed a modified version of the opinion-judging task used by Mitchell et al. (2006) Trials were divided into prime and self phases. Each trial began with the presentation of one of three primes: (i) the photograph of the liberal target, (ii) the photograph of the conservative target, or (iii) a chalk outline of a head with the word "me" written inside, used to represent the participant her or himself. This prime image appeared above a four-point response scale (1 = not at all and 4 = definitely). Simultaneously, an opinion question appeared between the prime and the response scale, and participants were asked to use the scale either to estimate how likely the target would be to endorse the opinion or, for the chalk outline, to report their own response to the question. Opinion questions referred to a range of personal issues that were pretested to be unrelated to political orientation (e.g., "dislike mushrooms on pizza?"; "enjoy crossword puzzles?"; "like to be the center of attention?"; "generally see things from many perspectives?"; "enjoy helping friends with problems?"; and "like impressionist artwork?")...

The self phase of each trial began after a 400-ms interval and was identical to the chalk outline prime described above, in which participants reported their own response to an opinion question.

So "the others" were sketchy fictitious characters who either liked or didn't like mushrooms on their pizza. Anyway, what are the behavioral correlates of such a manipulation? Were there any? This is important, because repetition suppression in certain brain regions that are more perceptual (such as the LOC or fusiform gyrus) is seemingly independent of behavioral priming (e.g., speeding up on primed trials relative to unprimed), whereas repetition suppression in other regions (such as prefrontal cortex) is sensitive to the response conditions and thus, behavioral priming (Horner & Henson, 2008).

But we don't get to read about reaction time data in the scanner.

...analysis of response time in the fMRI experiment was precluded by the abbreviated length of trials necessitated by rapid event-related scanning, such that participants were typically near the ceiling allowed by the response window [which seemed to be 3,600 ms].

Instead, a separate behavioral study showed that RTs were significantly faster after similar (M = 1,990 ms) than dissimilar (M = 2,079 ms) targets, but it seemed RTs were even more facilitated (299 ms faster) if the subject made the exact same response (e.g., pressing the 3 key) for similar other and self. But then they go on to say that a weakly-powered subanalysis of the fMRI data revealed that the repetition suppression effect was independent of response key. My head hurts now...

Sigh. One more detail about the actual region [singular] of interest, which was ventral medial prefrontal cortex (vMPFC). In their previous study (Mitchell et al., 2006), the "Like Me" region was located at MNI coordinates of 18, 57, 9 but the center of mass migrated to the opposite hemisphere at –6, 45, 3 in the present experiment ² (with an alternate vMPFC ROI of -3, 51, 12 in the Supplementary Material).


Fig. 1 (Jenkins et al., 2008). A region of vMPFC (–6, 45, 3; 47 voxels in extent) was defined from an explicit self-reference task in which judgments of one's own personality characteristics were compared with judgments of another person George Bush (i.e., self greater than Bush).

So there you have it.

ADDENDUM: And there's more! In the comments, Elliot highlights the faulty method used to initially identify the vMPFC region of interest shown above:

After the opinion-judging task, participants completed an explicit self-reference task... On each of 100 trials, participants saw a single trait adjective that could be used to describe a person's personality or dispositional traits (e.g., curious, intelligent, or neurotic). Each trait adjective was accompanied by the name of one of two targets: self or Bush.

As if opinions about Bush among even slightly liberal college students will be completely neutral! No confound with negative emotion there...

On what is perhaps a more useful note, you can read a thorough summary of mentalizing as it relates to clinical practice on the Menninger Clinic web site. Impairments in mentalizing about the minds of others have been widely reported in people with autism and schizophrenia, but more subtle deficits have also been observed in individuals with bipolar disorder, borderline personality disorder, and eating disorders. In fact, a brand new study (Bateman & Fonagy, 2008) reported some success in treating BPD with mentalization therapy:

BPD is traditionally treated with a combination of a specific type of psychotherapy (called dialectical behavior therapy) and sometimes medications to treat other specific, related concerns (such as depression).

But an alternative psychotherapy treatment approach is also available, called mentalization based therapy (MBT). This psychodynamic approach focuses on helping an individual separate out what thoughts and feelings are theirs, and what thoughts and feelings are others’. While this may seem like an obvious thing to know or how to do, it is theorized that people with borderline personality disorder often have difficulty with just this thing.

...five years after treatment was completed, people who received mentalization treatment did significantly better than those who didn’t (on measures such as suicidality, diagnosis, medication, global functional and use of additional treatment services).

So while it can be helpful to use introspection to infer the mental states of others (particularly those most "like you"), this method can be carried to counterproductive extremes.

Footnote

¹ also called Theory-of-Mind

The Sally-Ann Test

² Yes, I know the ROI was 47 voxels in extent. I'm just sayin'...

References

Bateman A, Fonagy P. (2008). 8-Year Follow-Up of Patients Treated for Borderline Personality Disorder: Mentalization-Based Treatment Versus Treatment as Usual. Am J Psychiatry Mar 17; [Epub ahead of print].

Horner AJ, Henson RN. (2008). Priming, response learning and repetition suppression. Neuropsychologia Feb 2; [Epub ahead of print].

Jenkins AC, Macrae CN, Mitchell JP. (2008). Repetition suppression of ventromedial prefrontal activity during judgments of self and others. Proceedings of the National Academy of Sciences, 105(11), 4507-4512. DOI: 10.1073/pnas.0708785105

One useful strategy for inferring others' mental states (i.e., mentalizing) may be to use one's own thoughts, feelings, and desires as a proxy for those of other people. Such self-referential accounts of social cognition are supported by recent neuroimaging observations that a single brain region, ventromedial prefrontal cortex (vMPFC), is engaged both by tasks that require introspections about self and by tasks that require inferences about the minds of others perceived to be similar to self. To test whether people automatically refer to their own mental states when considering those of a similar other, we examined repetition-related suppression of vMPFC response during self-reflections that followed either an initial reflection about self or a judgment of another person. Consistent with the hypothesis that perceivers spontaneously engage in self-referential processing when mentalizing about particular individuals, vMPFC response was suppressed when self-reflections followed either an initial reflection about self or a judgment of a similar, but not a dissimilar, other. These results suggest that thinking about the mind of another person may rely importantly on reference to one's own mental characteristics.

Mitchell, J.P., Macrae, C.N., and Banaji, M.R. (2006). Dissociable Medial Prefrontal Contributions to Judgments of Similar and Dissimilar Others. Neuron 50: 655–663.

We quit making out to attend this meeting
With old ladies on tremendous amounts of coke
And reeling, I hear my bad voice call
My wayward brain reels
My easily distracted brain reels

-Throwing Muses, Mercury
(free download on throwingmusic)!