Do We Know What Our Brain Is Doing?
Jesse Aragon Huston ('10), Kenton Hokanson ('08), Matthew Macellaio ('09), William Banks, Eve Isham
Benjamin Libet et al. (1983) compared the onset of a negative-going waveform (a "readiness potential," or "RP") which consistently preceded voluntary movement with his participants' report of when they became aware of the will ("W") to make that movement. He found that the pre-movement brain activity began before the reported point of conscious awareness of the decision to move, suggesting to Libet that even voluntary movements are initiated unconsciously. The current study investigates the validity of the interpretation of the reported "W" as meaningfully indicative of the onset of conscious will. We presented a tone between 5 and 60 ms after the participants completed a simple movement (pressing a button), intending to influence their perception of when their movement occurred. If, as the current authors hypothesize, "W" is subjectively determined by subtracting a constant time interval from the participant's perception of motion, then we would expect to see the reported "W" (the time of the decision to move) shift along with the audio tone, rather than remain locked to the physical act of movement. Our results, while preliminary, seem to support this hypothesis, showing a potential influence on "W" and promising EEG data from several cortical regions.
Funding provided by: SURP (Richter-KH); Sontag (WB)
Latino Parents and Language Brokering: Preliminary Story
Maria Rojas ('08), John Raymond Buriel
Many children of immigrant families serve as interpreters and translators for their families; these children are referred to as Language Brokers (LB). Past research on LBs has focused on the social and cognitive processes and outcomes of children who fulfill this role. However, very little is known about how parents decide which child becomes the family's primary LB, and how they feel about giving adult-like responsibilities to that child. Thus, the present qualitative research project (a) explores a parent's selection process; (b) investigates parents feelings regarding their parental authority during the brokering process; and (c) examines the age-related expectations of parents during brokering. The research project consisted of two in-depth focus groups (N=10) conducted in Spanish. The information gathered reveals that these Latino parents mainly consider the level of education, age and disposition of the child. Also, parents do not feel they relinquish any parental authority, though the child may try to challenge it at times. And parents are readily aware of the children's age-related cognitive limitations before asking them to translate a document or conversation. Considering the preliminary nature of this project, questions were raised regarding the relationship between language brokers and their parents. Further research should focus on the parent-child relationship and the developmental effects on a child's sense of family obligation.
Funding provided by: SURP
Stress Responses in the Sympatho-Adrenal Medullary System
Christina Lynn Voonasis ('08), Nicole Weekes
The sympatho-adrenal medullary (SAM) system has, to date, received little attention in stress research when compared to the responses of the hypothalamic-pituitary-adrenal (HPA) axis. With the recent development of noninvasive salivary measures of sympathetic stress reactivity (e.g., alpha-amylase), this second branch of the stress response is becoming more accessible to our investigation. The mechanisms by which the SAM system, which is primarily responsible for the cardiovascular and emotional responses to psychological and physical stress, produces its effects are not yet well elucidated. The purpose of the present review is to assist stress researchers in examination of this system, the results of which could have implications in medicine (through the effects SAM activation exerts upon the immune system and cardiovascular health), cognitive psychology (i.e., memory and learning alterations), and the further discovery of differential stress responses between the sexes. The present review summarizes the existing literature on SAM functions, raises methodological issues in the study of this system, and proposes new directions for future research.
Funding provided by: SURP