National Academy of Science/National Research Council Twin Study of Laterality and Survival Fitness (J. Jaffe, D. Ross, W. Page, E. Squires-Wheeler, S.W. Anderson, B. Beebe, W. Honer)
Sparked by the incredulous claim that left-handers have an 8-year shorter life expectancy than right-handers, this is the first twin test of a corollary hypothesis: In twin pairs who are discordant for laterality, the non-dextral will predecease the dextral. The NAS/NRC Twin Registry includes 2131 male twin pairs, all veterans of WWII, who provided complete laterality data in a 1985 re-survey. A 5-year follow-up revealed 317 pairs in which only one twin had died. Of these 317 pairs, 49 were discordant for handedness (25 DZ & 24 MZ). The hypothesis was confirmed only for MZ pairs, i.e., a dextral twin is likely to outlive his non-dextral brother whereas the order was reversed in DZ pairs (p < .01). Since MZ siblings share 100% of their genes whereas DZ siblings share only 50% of their genes, the latter are more representative of the general population. Thus, some special factor, perhaps intense, symbiotic social bonding, seems to apply to MZ twins. “Cause of death,” in addition to “fact of death,” is now being investigated in the Twin Registry.

Drs. Squires-Wheeler (behavior genetics of personality disorders in DSM Axis II) and Honer (genetics of schizophrenia) joined the team. Both share our basic interest in the genetics of sociability.

Dr. B. Beebe has 400 laterality questionnaires (fathers and mothers of first-born infants in our ongoing normal and depression studies), thus permitting critical inter-generational laterality comparisons between the geriatric Twin Registry sample and the “baby-boomers.” We hope to quantify the waning bias against sinistrality over the last century, a bias that still confounds most published handednesss studies.

In reponse to a recent proposal to detect and clone a “dextrality” gene, Dr. Anderson (an expert on sinistrality) initiated a critical analysis of handedness questionnaires (such as our own) on which most epidemiologic theories of handedness genetics are based.

World Trade Center Disaster (Beebe, Jaffe)
This is a new project to treat compromised mother-infant communication in women who were pregnant and widowed on 9/11/01. In addition to group therapy for all mothers, the project features a therapeutic/educational “Video-Bonding Consultation” with the mother. This is a 90- minute intervention, based upon a split-screen videotape of mother-infant and stranger-infant face-to- face play, both recorded within the same hour. Since Dr. Beebe is both the consultant and the stranger on the videotape, the mother and Dr. Beebe share the unique experience of playing with the same infant within several minutes of each other. Although a plethora of behavioral events might be chosen for special notice and interpretation in these interventions, the actual choices are both psychodynamically informed and evidence-based. Each such choice is the product of three decades of basic science, i.e., automated and videotape analyses of normal and disturbed non-verbal communication. Thus, this consultation is another example of translational research in our program. Below is a sample video-still taken from a recorded split-screen session.

Mother-infant Regulation: Depression and Attachment (Beebe, Jaffe, Chen, Cohen, Feldstein, Anderson)
The third full year of this NIMH-funded project coincided with the International Conference on Infant Studies in Toronto, Canada where Beebe et al (2002) presented “Mother-infant 4-month self- and interactive regulation: Anxiety, depression and attachment.” Also finally published are: Beebe et al, (2002) “ Koordination von Sprachrhythmus und Bindung;” Crown et al (2002) “The cross-modal coordination of interpersonal timing;” and Koulomzin, Beebe, Anderson, et al (2002) “Infant gaze, head, face and self-touch at 4 months differentiate secure vs. avoidant attachment at one year: A microanalytic approach.”

Mirror Neuron Theory (Anderson, Jaffe)
A new interpretation of our conversational research (including adult infant interactions) is based on the recent discovery of a new cell type in the premotor cortex. Dubbed "mirror neurons" by their discoverers, they have now been found to be distributed across the entire motor homunculus (that previously was thought to be simply a motor-control region). However, MRI studies show that these neurons are also “sensory,” i.e., they respond to the passive observation of specific goal-directed movements of mouth, hand or foot when performed by another person. One could argue that if mirror neurons didn’t exist we would have had to invent them. For example, Pavlov (1928) reported that, in dogs, conditioned reflexes which had been elaborated on the skin surface of one-half of the body are obtainable to exactly the same degree from the stimulation of corresponding symmetrical points on the other half, even though the latter have never been tested before. Jaffe & Bender (1952) related this finding to the “mirror image spread of pain” syndrome as well as to the uncanny resilience of symmetrical, as opposed to asymmetrical cutaneous stimulation during organic confusional states in humans. But these early studies referred mainly to “within-person” symmetry (bidirectionality). Subsequent studies of conduction aphasia, echolalia and echopraxia led to the hypothesis of a “neural imitative mechanism” (Dahlberg & Jaffe, 1977), i.e., a “between-person” or “dyadic” bidirectionality, the need for which is now firmly established by demonstration of nonverbal mimicry at birth (Meltzoff & Moore, 1992). In our current interpersonal application, we have assumed for decades that conversational entrainment between dialogic partners is accomplished by sequential constraints in a time series, where signals of speaking and pausing at time t constrain behaviors occurring at time t + 1. Anderson has developed dozens of Markov models, based on varying numbers of constraining states sampled at various rates, only to find that even mothers and babies "chime in" on each other in ways that these models cannot explain. He presented the problem posed for these models in Paris (1994) since simultaneous interpersonal cooperation was occurring within fractions of seconds, much too often according to our predictions. He subsequently proposed that if there are mirror neurons that track social interactions, including speech as well as gesture, then it is possible that simultaneous mirroring of one's observations and actions could result in time locking of simultaneously perceived and performed events. A paper by Anderson, Koulomzin, Beebe & Jaffe, entitled, “Visual attention and self grooming behaviors among 4 month infants: Indirect evidence pointing to a developmental role for mirror neurons” is in press. We are now seeking evidence to confirm the prediction that there are mirror neurons in Broca's motor speech area that respond when speech is perceived, supporting the motor theory of language.