Skip to Content

Psychological Sciences

Home > Events > Events

Events

Department of Psychology Special Seminar with Zachary Roper
August 7, 2015

 Hosted by the Woodman lab

Zachary J. Roper, Psychological and Brain Sciences, University of Iowa

Friday, August 7, 2015

Noon. Wilson Hall, Room 316

Is the attentional humunculus a rational economic actor?

Visual attention selects stimuli for further cognitive processing. It has been shown that reward can bias this attentional selection process. Specifically, value-driven attentional selection promotes survival and wellbeing by supposedly guiding an organism toward stimuli associated with rewarding outcomes. However, it is unknown to what extent attentional selection acts in an economically rational way. On the one hand, animal learning literature suggests that an organism’s behavior closely reflects total potential gains across a variety of factors (e.g., reward magnitude, reward probability, delay until reward, etc.).  On the other hand, there is evidence from economic decision-making research suggesting that humans consistently behave irrationally (e.g., loss-aversion, underweighting low frequency events, etc.). In a series of five experiments we demonstrated attentional capture to colored stimuli that were previously associated with reward. Attentional capture was sensitive to reward magnitude and reward probability; however, these effects resembled classic non-linear distortions. Namely, we observed underweighting of high probability rewards. We conclude that the attentional homunculus is not a rigid, rational economic actor but instead operates flexibly in a manner akin to prospect theory (Kahneman & Tversky, 1979). 


CCN Brown Bag Series: Gordon Logan
August 26, 2015

Gordon Logan, Ph.D., Department of Psychology, Vanderbilt University

Wednesday, Aug. 26, 2015

12:10 p.m. Wilson Hall, Room 115

Title and abstract: TBA


Clinical Brown Bag Series: Steve Hollon
September 1, 2015

Steve Hollon, Ph.D., Department of Psychology, Vanderbilt University

Tuesday, Sept. 1, 2015

12:10 p.m. Wilson Hall, Room 316

"Is Cognitive Therapy Enduring or are Antidepressant Mediations Iatrogenic?"

 

Cognitive therapy appears to have an enduring effect that reduces risk for subsequent relapse and recurrence by about half relative to antidepressant medications following treatment termination. However, these conclusions are almost wholly derived from direct comparisons between prior cognitive therapy versus prior medication. Findings from the extended maintenance phase of our most recent trial suggest that cognitive therapy provided in combination with medication does little to prevent subsequent recurrence. These findings raise the concern that adding medications may interfere with the enduring effects of cognitive therapy as they do in panic. Moreover, depression appears to have “coarsened” over recent decades and there are concerns that antidepressant medications may suppress symptoms at the expense of prolonging the underlying episode. Antidepressant medications are known to work by perturbing the complex homeostatic regulatory systems that underlie affective response and differences in that perturbation are associated with risk for relapse following medication discontinuation. It remains unclear whether cognitive therapy truly has an enduring effect or antidepressant medications have an iatrogenic effect that that either interferes with cognitive therapy’s enduring effect or (even worse) prolong the length of the underlying episode. Studies are described that could resolve this issue and the potential implications discussed.


CCN Brown Bag Series: Tom Palmeri
September 2, 2015

Tom Palmeri Ph.D., Department of Psychology, Vanderbilt University

Wednesday, Sept. 2, 2015

12:10 p.m. Wilson Hall, Room 115

Topic and abstract to be announced.

 


Clinical Brown Bag Series: Steve Brunwasser
September 8, 2015

Steve Brunwasser, Kennedy Center for Research, Vanderbilt University

Tuesday, Sept. 8, 2015

12:10 p.m. Wilson Hall, Room 316

Title and abstract: TBA


CCN Brown Bag Series: Ming Meng
September 9, 2015

Ming Meng, Ph.D., Center for Social Brain Sciences. Dartmouth University

Wednesday, Sept. 9, 2015

12:10 p.m. Wilson Hall, Room 115

Fluctuations of fMRI activation patterns underlie the theta-band rhythmic effects of visual object priming

To efficiently interact with an ever-changing environment, the brain dynamically responds to sensory stimulation. Notably, whereas high-frequency gamma band activity may directly underlie neuronal spike coordination (Crick & Koch, 1990), slower waves carrying (multiplexing) faster waves appear to be a common perceptual coding strategy in the brain (VanRullen & Koch, 2003). Recent behavioral studies further suggest a theta-band rhythm (4-7 Hz) in the effects of attention and priming (e.g., Fiebelkorn, Saalmann, & Kastner, 2013; Song et al., 2014; Huang, Chen, & Luo, 2015). Here, I investigate three possible brain mechanisms that may lead to such rhythmic behavioral effects: 1) object representations may be rhythmic in the inferior temporal (IT) cortex; 2) Object representations may be constant, but attentional selection of the representations may be rhythmic; 3) Sensory sampling may be rhythmic as early as the primary visual cortex, therefore all the subsequent processes may also be rhythmic. To test these possibilities, activity corresponding to visual object priming was measured in regions of interest (ROIs) across the whole brain by using fMRI.  Critically, to examine rhythmic effects, time-resolved measurements of fMRI activation patterns were attained by varying trial-by-trial stimulus onset asynchrony (SOA) between prime and probe in small steps of 20ms (equivalent to a 50Hz sampling rate). Our behavioral results replicated previous findings, showing theta-band oscillations in the priming effects of reaction times as a function of SOA. More interestingly, multivariate pattern analysis of the fMRI data also demonstrated theta-band oscillations as a function of SOA and an out-of-phase relationship between congruent and incongruent conditions in the IT cortex. No such effects were found in the BA17 or the frontoparietal attention network. This study is the first to map theta-band rhythms across the whole human brain using fMRI. Our results suggest that object representation is oscillatory with theta-band rhythms in the IT cortex, providing insights to understanding the dynamic mechanisms underlying visual perception.

 


Clinical Brown Bag Series: Carissa Cascio
September 15, 2015

Carissa Cascio, Child and Adolescent Psychiatry, Vanderbilt University Medical Center

Tuesday, Sept. 15, 2015

12:10 p.m. Wilson Hall, Room 316

TITLE AND ABSTRACT: TBA


CCN Brown Bag Series: Miguel Eckstein
September 16, 2015

Miguel Eckstein, Ph.D., Psychological & Brain Sciences, UC Santa Barbara

Wednesday, Sept. 16, 2015

12:10 p.m. Wilson Hall, Room 115


Clinical Brown Bag Series: Andre Christie-Mizell
September 22, 2015

Andre Christie-Mizell, Ph.D., Sociology Department, Vanderbilt University

Tuesday, Sept. 22, 2015

12:10 p.m. Wilson Hall 316

TITLE AND ABSTRACT: TBA


CCN Brown Bag Series: Sean Polyn
September 23, 2015

Sean Polyn, Ph.D., Department of Psychology, Vanderbilt University

Wednesday, Sept. 23, 2015

12:10 p.m. Wilson Hall, Room 115

Title and Abstract: TBD


Showing 1–10 out of 20        « Previous | Next »


» View archived events

©