Sunday, February 27, 2011

And the Oscar Goes to...



Inspired by Natalie Portman's portrayal of a mentally unbalanced ballerina? Or by Colin Firth's role as a stuttering king? Want to direct your own Social Network like David Fincher?

The Society for Neuroscience is sponsoring a video contest! So it might be more appropriate to use the Oscar nominees for Best Documentary Short Subject as your role models.

About the Contest

Convey a neuroscience concept on video!

The Society for Neuroscience (SfN) challenges you to make an original video, up to five (5) minutes long, demonstrating a concept about the brain that could be used as a teaching tool or resource. Whether it's through animation, song, or reenactment, share the wonders of science through the Brain Awareness Video Contest.

Brain Awareness Week (BAW) is an inspirational global campaign that unites those who share an interest in elevating public awareness about the progress and benefits of brain and nervous system research.

Top prize is $1,000 and a free trip to Washington DC, plus complimentary registration to Neuroscience 2011 [up to $650 in value!]! You needn't be a member of SfN to enter the contest, but your video must be submitted by a member.

More details on how to enter are available at the contest website.

Lights, camera, action!

Saturday, February 26, 2011

Is Mourning Rewarding?


Light projection by Jenny Holzer
Poetry by Mahmoud Darwish (He Embraced His Murderer)


Rejection in love (Fisher et al., 2010) and complicated grief (O'Connor et al., 2008) as rewarding phenomena?

Fig. 1 (Fisher et al., 2010). Group regional activation specific to the rejector stimulus in reward systems and other areas. A: axial view. Ventral tegmental area (VTA, right arrow). The VTA regions overlap those affected when looking at a lover while happily in love (Aron et al., 2005). The cross hair (middle arrow) marks an area of activation that includes the nucleus accumbens and ventral pallidum.


Fig. 2A (O'Connor et al., 2008). Nucleus accumbens activity (10, 20, −6) in response to grief-related vs. neutral words that was significantly greater in the Complicated Grief group compared to the Noncomplicated Grief group (pictured at p < .05).


If tremendous psychological suffering and loss are associated with activity in brain regions such as the ventral tegmental area and nucleus accumbens, isn't it time to abandon the simplistic notion of dopamine as the feel-good neurotransmitter? To quote the authors of Mesolimbic Dopamine in Desire and Dread (Faure et al., 2008):
It is important to understand how mesocorticolimbic mechanisms generate positive versus negative motivations. Dopamine (DA) in the nucleus accumbens is well known as a mechanism of appetitive motivation for reward. However, aversive motivations such as pain, stress, and fear also may involve dopamine in nucleus accumbens (at least tonic dopamine signals).

References

Faure A, Reynolds SM, Richard JM, Berridge KC. (2008). Mesolimbic dopamine in desire and dread: enabling motivation to be generated by localized glutamate disruptions in nucleus accumbens. J Neurosci. 28:7184-92.

Fisher HE, Brown LL, Aron A, Strong G, Mashek D. (2010). Reward, addiction, and emotion regulation systems associated with rejection in love. J Neurophysiol. 104:51-60.

O'Connor MF, Wellisch DK, Stanton AL, Eisenberger NI, Irwin MR, Lieberman MD. (2008). Craving love? Enduring grief activates brain's reward center. Neuroimage 42:969-72.


Sample stimulus from Fig. 1 of O'Connor et al., 2008 provides an [unintentional?] example of the emotional Stroop effect.

Sunday, February 20, 2011

Is Romantic Love a Western, Heterosexual Construct?


ROMANTIC LOVE WAS INVENTED TO MANIPULATE WOMEN

-Jenny Holzer, Truisms

Does romantic love manipulate women into providing free domestic labor and sexual favors for men? Some feminist views of romantic love [and the institution of marriage] portray it as controlling and oppressive (Burns, 2000):
‘STOP HUMAN SACRIFICE. END MARRIAGE NOW.’ ‘IT STARTS WHEN YOU SINK IN HIS ARMS AND ENDS WITH YOUR ARMS IN HIS SINK.’ From a feminist perspective, romantic love was, and is, seen to obscure or disguise gender inequality and women’s oppression in intimate heterosexual relationships.
But some in the men's movement see romantic love as dangerous for men as well as women, because it prevents men from being vulnerable (Bloodwood, 2003):
...historically, romantic love has been a highly gendered but workable deal in which men provide women with social status and material goods while women provide men with sex/affective labour. Thus romantic relationships not only reinforce women’s second class status but also reinforce men’s lack of sex/affective autonomy, so that romantic love is equally dangerous for women and for men.
Furthermore, romantic love is often portrayed as a relatively recent construct that is specific to Western societies. A cross-cultural study by Jankowiak and Fischer (1992) claimed that:
The anthropological study of romantic (or passionate) love is virtually nonexistent due to the widespread belief that romantic love is unique to Euro-American culture. This belief is by no means confined to anthropology. The historian Philippe Aries (1962), for example, argues that affection was of secondary importance to more utilitarian ambitions throughout much of European history.
However, their own analysis of the ethnographic literature found that romantic love (however ill-defined) could be observed in 147 out of 166 societies, including 77% in Sub-Saharan Africa and 94% in East Eurasia (Jankowiak & Fischer, 1992). Likewise, evolutionary anthropologist Helen Fisher and colleagues suggest that romantic love evolved as one of three motivational brain systems for mating, reproduction, and parenting (Fisher et al., 2002).

The biological concept that romantic love (or attraction) is an emotional/motivational system in the human brain has prompted some neuroimaging investigators to search for its elusive neural correlates. How do you measure long-term intense romantic love in an fMRI experiment? Researchers have adopted the practical (yet flawed) strategy of examining the hemodynamic response to viewing pictures of a partner with whom participants were "madly in love".

Previous studies on the "neural correlates of romantic love" have focused on recently attached heterosexuals from the UK (Bartels & Zeki, 2000) or US (Aron et al., 2005). One of the main findings from these studies is that the expected dopamine/reward areas [including ventral tegmental area (VTA), substantia nigra (SN), and caudate nucleus] showed greater activation when looking at the pictures of the partner, compared to pictures of a close friend or neutral acquaintance. And in the previous post on Posterior Hippocampus and Sexual Frequency, we saw a similar response in a specifically recruited group of participants still "madly in love" after 21 years of marriage (Acevedo et al., 2011).

So are the "neural correlates of romantic love" the same in non-Western, non-heterosexual participants? Two recent papers attempted to spread the love to include diverse "others" (Xu et al., 2011; Zeki & Romaya, 2010). Is the simple act of asking if the Chinese and teh gays are "just like us" when it comes to love offensive? I'll let you be the judge.

Although the original study of Bartels and Zeki (2000) recruited an ethnically and culturally diverse group of subjects, all were heterosexual. Zeki and Romaya (2010) wanted to extend this work to include romantically involved gay participants. This time, they included 12 females (6 in straight and 6 in lesbian relationships) and 12 males (6 in straight and 6 in gay relationships) in their fMRI experiment. I won't belabor the methods [and the critiques thereof] here, but will refer the reader to Posterior Hippocampus and Sexual Frequency.1


Fig. 2 (Zeki & Romaya, 2010). Illustration of the t statistic for the contrast Loved > Neutral showing selected activations superimposed over averaged anatomical sections. Random effects analysis with 24 subjects. Background threshold p uncorrected < 0.001. (A) Medial sagittal plane (x = 0) showing activations in the tegmentum [VTA], hypothalamus and [cerebellar] vermis. (B) Sagittal plane x = −12 (LH) showing activation in the caudate head, anterior cingulate and parietal cortex. (C) Horizontal plane z = −30; right cerebellum. (D) Horizontal plane z = −9; mid insula, left hemisphere.


As for differences between the groups, there were none: no main or interactive effects of gender or sexual orientation. The results were the same for gay and straight, male and female participants [but remember that the numbers were very low, n=6 for each of the four cells]. So this particular [underpowered] study suggests that "the romantic love brain circuit" (i.e., familiarity, attention, memory, reward, etc. activity associated with looking at your partner's face) is not restricted to heterosexuals. Did they really expect anything different? Actually not, Zeki and Romaya predicted a null effect.

However, the authors themselves note the difficulties inherent in their entire endeavor:
We begin by emphasizing that any study of so complex and overpowering a sentiment as love is fraught with difficulties. Chief among these is that the sentiment itself involves many components – erotic, emotional, and cognitive – that are almost impossible to isolate from the overall sentiment of love. ... While acknowledging this difficulty, we tried as best we could to circumvent it, by applying a uniform criterion – that of a loved face – for studying the brain's love system. Another problem is the difficulty of controlling the mental processes that occur when subjects view their lovers' faces. The only way to address this is through the statistical methods we have used to analyze our results. We have employed a random effects analysis using the summary statistic approach to control for the between-subject variation in our sample.

Finally, to complete our neurological query on the universal nature of romantic love, how about the cross-cultural findings? What were the results in 18 heterosexual Han Chinese students recruited from Beijing Normal College (Xu et al., 2011)? Why, the same VTA and caudate regions were activated by the beloved!
The findings of this study of early stage intense romantic love in China suggest that (a) highly similar patterns of reward system activation in response to one's beloved are found in Chinese as in the United States...
There were however some differences, namely in the orbitofrontal cortex:
Thus, it is possible that Chinese participants may engage orbitofrontal systems and afferents, weigh the relationship more carefully, and take negative aspects into account more readily than Western participants (orbitofrontal cortex activation was not found in US and UK samples)...
What does all this mean for the question posed in title of this post? We can't answer it, at least as far as the brain is concerned. We can't go back in time and scan people from the past, obviously. How about recruiting individuals who live in the 11.5% of societies where romantic love was not reported? Good luck with that.

I'll leave you with a novel control experiment. None of the studies have compared gazing at the partner's face to a condition I'll call "the most desired celebrity." Have the participants in this devious new study view a picture of who they consider the single hottest actor, and see how well the beloved holds up against Brad or Angelina [for instance]. Dare you tell your partner the outcome of this little experiment?

Footnote

1 There were some minor differences in stimulus presentation parameters between Zeki's and Aron's groups, but we'll skip those for now.

References

Acevedo BP, Aron A, Fisher HE, & Brown LL (2011). Neural correlates of long-term intense romantic love. Soc Cogn Affect Neurosci. Jan 5. [Epub ahead of print].

Aron A, Fisher H, Mashek DJ, Strong G, Li H, Brown LL. (2005). Reward, motivation, and emotion systems associated with early-stage intense romantic love. J Neurophysiol. 94:327-37.

Bartels A, Zeki S. (2000). The neural basis of romantic love. Neuroreport 11:3829-34.

Burns A (2000). IV. Looking for Love in Intimate Heterosexual Relationships. Feminism & Psychology 10:481-485. PDF

Bloodwood D (2003). The Dangers of Romantic Love. Unpublished Manuscript. PDF

Fisher HE, Aron A, Mashek D, Li H, Brown LL. (2002). Defining the brain systems of lust, romantic attraction, and attachment. Arch Sex Behav. 31:413-9.

Jankowiak WR, Fischer EF (1992). A Cross-Cultural Perspective on Romantic Love. Ethnology 31:149-155.

Xu, X., Aron, A., Brown, L., Cao, G., Feng, T., & Weng, X. (2011). Reward and motivation systems: A brain mapping study of early-stage intense romantic love in Chinese participants. Human Brain Mapping, 32 (2), 249-257 DOI: 10.1002/hbm.21017

Zeki, S., & Romaya, J. (2010). The Brain Reaction to Viewing Faces of Opposite- and Same-Sex Romantic Partners. PLoS ONE, 5 (12) DOI: 10.1371/journal.pone.0015802


Monday, February 14, 2011

Posterior Hippocampus and Sexual Frequency

Fig. 2D (Acevedo et al., 2011). Image and scatter plot illustrating greater response to the Partner (vs. a highly familiar acquaintance) in the region of the posterior hippocampus is associated with higher sexual frequency.


Now there's an unexpected correlation suitable for Valentine's Day. How romantic! Actually, it is romantic because the neuroimaging study by Acevedo et al. (2011) is entitled "Neural correlates of long-term intense romantic love." How do you quantify long-term intense romantic love in an fMRI experiment?

Well, what the study really examined is the brain's hemodynamic response to viewing pictures of a spouse with whom participants were still "madly in love" after an average of 21 years. Over the course of the experiment, subjects repeatedly viewed four different digital photos: Partner, Close Friend (CF), Highly Familiar "Neutral" acquaintance (HFN), and a Low-Familiar Neutral acquaintance (LFN). Specifically,
The protocol implemented a block design of two 12-min sessions each consisting of six sets of four 30-s tasks in an alternating fashion, followed by stimulus ratings. Each session included two alternating images (starting image counterbalanced), interspersed with a count-back task. Duplicating procedures of Aron et al. (2005), Session 1 displayed Partner and HFN images. For the additional control comparisons, Session 2 displayed CF and LFN images. Participants were instructed to think about experiences with each stimulus person, nonsexual in nature.
Yeah, it might be a problem if the participants remembered bouts of sex when they viewed their partners... Fig. 2D shows that activation in a tiny area of the left posterior hippocampus correlated with sexual frequency. The two outliers who had sex every day (or nearly every day)1 could be driving the correlation -- they certainly had a greater number of memories to choose from, and to suppress. In humans, activity in the posterior hippocampus is sensitive to the familiarity of stimuli that have behavioral relevance (Strange et al., 1999), and is associated with memory for repeated stimuli (Poppenk et al., 2010).

How do Acevedo et al. (2011) interpret this correlation?
Although little is known about the posterior hippocampal region [NOTE: untrue], some studies have shown increased activation in this area in association with hunger and food craving (LaBar et al., 2001; Pelchat et al., 2004), with particularly greater activity shown in obese individuals (Bragulat et al., 2010).
Craving, eh? Not memory? Although the authors would like to think they controlled for familiarity with the Close Friend contrast, it seems to me nearly impossible that a co-worker, sibling, cousin, or friend could fulfill all familiarity criteria except romantic relationship. Furthermore, most of the analyses focused on comparisons between Partner vs. Highly Familiar Neutral 2 to match their previous paper (Aron et al., 2005) on the early stages of romantic love (1-17 months in duration).

I could go on about the analysis methods, and whether reporting the single voxel with highest activity is appropriate [see Voodoo Correlations]. Or I could go on about the subject selection criteria: the 17 heterosexual participants (10 women, 7 men, ages 39-67 yrs, married 10-29 yrs) had an annual household income ranging from $100,000-$200,000 (perhaps not representative of the general population).

But what about the main findings? Am I just being a cynic when it comes to love? It's true, some of the expected dopamine/reward areas [ventral tegmental area (VTA) and substantia nigra (SN)] showed greater activation when looking at the long-term Partner, which was very much like what was seen in the young lovers.

Fig. 2A (Acevedo et al., 2011). Individuals self-reporting intense love for a long-term spouse show significant neural activation in dopamine-rich, reward regions of the VTA/SN in response to images of their partner vs a highly familiar acquaintance.

Ultimately, the paper sends a positive message that in certain relationships, the exciting, obsessive, and rewarding period of intense romantic love can last for over 20 yrs, well beyond the typical and oft-cited (oprah.com)3 18 month to 3 year duration:
IMPLICATIONS
Individuals in long-term romantic love showed patterns of neural activity similar to those in early-stage romantic love. These results support theories proposing that there might be mechanisms by which romantic love is sustained in some long-term relationships. For example, the self-expansion model suggests that continued expansion and novel, rewarding events with the beloved may promote increases in romantic love. Novel, rewarding experiences may use dopamine-rich systems (Schultz, 2001; Guitart-Masip et al., 2010) similar to those activated in this study.
Beyond reporting relationship length (and sexual frequency), the participants filled out questionnaires including the Passionate Love Scale, the Love Attitudes Scale, the inclusion of other in the self (IOS) Scale, and the friendship-based love scale. All indicators suggested that the subjects were still "madly in love" with their partners. Did we really need neuroimaging to tell us that? Maybe...


Image from The Science of Love


Footnotes

1 The mean sexual frequency was 2.2 times a week.

2 The HFN has been known about as long as the Partner, but is substantially less close than both the Partner and the Close Friend.

3 If anyone can find a better reference for this than oprah.com or Tennov, D., 1979. Love and limerence. The Experience of Being in Love. Stein and Day, New York -- let me know.


References

Acevedo BP, Aron A, Fisher HE, & Brown LL (2011). Neural correlates of long-term intense romantic love. Social cognitive and affective neuroscience PMID: 21208991

Aron A, Fisher H, Mashek DJ, Strong G, Li H, Brown LL. (2005). Reward, motivation, and emotion systems associated with early-stage intense romantic love. J Neurophysiol. 94:327-37.

Poppenk J, McIntosh AR, Craik FI, Moscovitch M. (2010). Past experience modulates the neural mechanisms of episodic memory formation. J Neurosci. 30:4707-16.

Strange BA, Fletcher PC, Henson RN, Friston KJ, Dolan RJ. (1999). Segregating the functions of human hippocampus. Proc Natl Acad Sci. 96:4034-9.

Thursday, February 10, 2011

Phrenology, Then and Now

In the November 2010 issue of Perspectives in Psychological Sciences, a Special Section on "Neuroimaging: Voodoo, New Phrenology, or Scientific Breakthrough?" (Diener, 2010) looks back at the infamous paper by Vul et al. (2009) and forward into the future. In one of the articles, an extended analogy is made between modern neuroimaging and the phrenology of yore (Poldrack, 2010):
Imagine that fMRI had been invented in the 1860s rather than the 1990s. Instead of being based on modern cognitive psychology, neuroimaging would instead be based on the faculty psychology of Thomas Reid and Dugald Steward, which provided the mental “faculties” that Gall and the phrenologists attempted to map onto the brain. Researchers would have presumably jumped from phrenology to fMRI and performed experiments manipulating the engagement of particular mental faculties or examining individual differences in the strength of the faculties. They almost certainly would have found brain regions that were reliably engaged when a particular faculty was engaged and potentially would also have found regions in which activity correlated with the strength of each faculty across subjects.
Gall's ambition and vanity are now 'activation for judgment about self versus others', localized to medial prefrontal cortex. Friendly attachment/fidelity have been transformed into 'viewing a friend versus viewing a stranger', associated with right temporoparietal cortex.

-- click on image for larger view--



Table 1 (Poldrack, 2010). A Mapping of Gall's 27 Faculties to Potentially Related Neuroimaging Research.
Although few today would hold that 19th century faculty psychology is an accurate description of the structure of the mind, we can likely all agree that if the phrenologists had created task manipulations to isolate their proposed faculties using fMRI, something would have “lit up.” What would the patterns of activation associated with these faculties have looked like? If we believe, as I think most would agree, that each of the phrenologists' putative faculties relies in actuality upon a combination of basic mental operations, then we would likely expect that the maps obtained for a given faculty would include a large set of activated regions that would tend to overlap across tasks meant to tap into different faculties. Regardless, one can be almost certain that Gall and his contemporaries would have taken these neuroimaging results as evidence for the biological reality of his proposed faculties.
But we know better now, don't we? Because Neural Networks Debunk Phrenology!
The studies show that network interactions among anatomically discrete brain regions underlie cognitive processing and dispel any phrenological notion that a given innate mental faculty is based solely in just one part of the brain.
Does anyone really believe in phrenology any more? Who advocates such a view? Cognitive neuropsychologists? Single-unit neurophysiologists? OR has localization of function in discrete networks (rather than an individual structure or a bump on the head) become the new phrenology? I think the story goes like this: complex adaptive behavior is an emergent property of network interactions. This is certainly not a new idea (see any number of publications by Joaquin Fuster)...

According to Poldrack (2010), neuroimaging research strategies have evolved from “where” (blobology or neophrenology) to “what” (characterize function of a specific brain region) to “fractionation” (determine whether different mental processes engage different brain regions). Ultimately, localization of function is still the final goal... as it was for the original phrenologists:
Phrenology teaches us that in this life every act of the mind is performed through the instrumentality of the brain, and that peculiar states of this organ invariably accompany particular mental dispositions.

-M.B. Sampson Esq. (1842)

References

Diener E (2010). Neuroimaging: Voodoo, New Phrenology, or Scientific Breakthrough? Introduction to Special Section on fMRI. Perspectives on Psychological Science 5:714-715.

Poldrack, R. (2010). Mapping Mental Function to Brain Structure: How Can Cognitive Neuroimaging Succeed? Perspectives on Psychological Science, 5 (6), 753-761 DOI: 10.1177/1745691610388777

Sampson MB (1842). PHRENOLOGY IN ITS APPLICATION TO THE TREATMENT OF CRIMINALS. The Lancet 37:639-643.

Vul E, Harris C, Winkielman P, Pashler H (2009). Puzzlingly High Correlations in fMRI Studies of Emotion, Personality, and Social Cognition. Perspectives on Psychological Science 4:274-290.

Thursday, February 3, 2011

Buyology Phrenology?


Four by four matrix of Neurotypes™ according to Buyology Inc™

Neuromarketing firm Buyology Inc™ has released its Most Desired U.S. Brands Report:
Johnson & Johnson, Sony, Mastercard and Kleenex Most Desired Brands for Women
Amazon Beats Walmart as the Most Desired Retailer
BMW, Hyundai and Lexus Among Most Desired Brands for Men

February 2, 2011 (New York, NY) – Johnson & Johnson, Sony, Crest and BMW appear at the top of the First Annual "Most Desired Brands in the U.S." Report. The report, released by leading global strategic neuromarketing firm Buyology Inc, is the first to quantitatively type and measure consumer relationships with brands. The full report can be found at www.buyologyinc.com.

The Most Desired U.S. Brands Report is the result of more than 6 years and $8 million, testing 240 global brands with more than 5000 consumers.
Here are the top 5:

RankWomenMen
#1Johnson & JohnsonCrest
#2SonyBMW
#3KleenexNational Geographic
#4National GeographicPanasonic
#5MasterCardHyundai

The Brand Most Desired by Men in the U.S. is Crest? Hyundai (#5) is more desirable than Lexus (#10)? Really? Roger Dooley discussed these and some of the other less predicted [i.e., completely surprising] findings at his Neuromarketing blog, noting that "The actual methodology used to produce this brand ranking is a bit sketchy."

So what are the elusive Neurotypes™?
Neurotypes™ quantitatively determine which of sixteen relationships a brand or business currently has for a given target audience and the relative strength of the relationship, or signal strength, relative to competitors and other, beacon brands who, although they may be outside the category, have successfully established similar relationships. Once typed and calibrated, a marketer can use Neurotypes to assess the impact of their current marketing activities, determine what activities will be more effective in the future and gain provocative and proprietary insights on how to strengthen the brand's relationships across the 6P framework (product, package, placement (distribution), price, promotion and positioning).
The Neurotype™ matrix yields a few surprises of its own. Taco Bell relates to its audience through Superiority and Harmony [just like Apple]. In contrast, Crest exploits the winning combination of Harmony and Superiority. Wal-Mart has a relationship of Exploration and Harmony with its customers [just like Facebook].

I'm reminded of the four personality types according to chemistry.com:



Each of these chemistry types is associated with a dominant neurotransmitter or hormone (serotonin, testosterone, dopamine, estrogen), according to resident anthropologist Dr. Helen Fisher. Although a simplistic caricature of personality differences, at least the proposed biological correlates are obvious.

But where does the neuro enter the marketing picture for Neurotypes™?
Buyology has developed proprietary physiological measurements based on brain and eye reaction to marketing stimulus that directly impacts in-market performance. These measures are collected either via Central Location Testing utilizing medical grade EEG and state-of-the art eye tracking equipment or via a global pre-recruited in-home panel via web-based stimuli and Bluetooth EEG collection equipment. The in-home methodology is web based, scalable and offers the client very quick results at a much lower cost while still providing superior results gathered in a more natural, in-home environment.
Non-conscious Marketing Stimuli Testing Output


Of course, we'll never be able to evaluate any of this, because the proprietary research is not peer reviewed. So it's black box phrenology, without the convenient localization map of its ancestors.