Top-down and Bottom-up influences on ACC activation: Evaluation of a proposed model of the feedback-related negativity

The Feedback-Related Negativity (FRN) is thought to reflect the dopaminergic prediction error signal from the subcortical areas to the ACC (i.e., a bottom-up signal). Two studies were conducted in order to test a new model of FRN generation, which includes direct modulating influences of medial PFC (i.e., top-down signals) on the ACC at the time of the FRN. Study 1 examined the effects of one’s sense of control (top-down) and of informative cues (bottom-up) on the FRN measures. In Study 2, sense of control and instruction-based (top-down) and probability-based expectations (bottom-up) were manipulated to test the proposed model. The results suggest that any influences of medial PFC on the activity of the ACC that occur in the context of incentive tasks are not direct. The FRN was shown to be sensitive to salient stimulus characteristics. The results of this dissertation partially support the reinforcement learning theory, in that the FRN is a marker for prediction error signal from subcortical areas. However, the pattern of results outlined here suggests that prediction errors are based on salient stimulus characteristics and are not reward specific. A second goal of this dissertation was to examine whether ACC activity, measured through the FRN, is altered in individuals at-risk for problem-gambling behaviour (PG). Individuals in this group were more sensitive to the valence of the outcome in a gambling task compared to not at-risk individuals, suggesting that gambling contexts increase the sensitivity of the reward system to valence of the outcome in individuals at risk for PG. Furthermore, at-risk participants showed an increased sensitivity to reward characteristics and a decreased response to loss outcomes. This contrasts with those not at risk whose FRNs were sensitive to losses. As the results did not replicate previous research showing attenuated FRNs in pathological gamblers, it is likely that the size and time of the FRN does not change gradually with increasing risk of maladaptive behaviour. Instead, changes in ACC activity reflected by the FRN in general can be observed only after behaviour becomes clinically maladaptive or through comparison between different types of gain/loss outcomes.

We need to have a conversation about OpenURL, a close look at a corpus of error reports from the 2013 academic year. Or, How I learned to stop worrying and give up on clean metadata.

Presented at Access 2014, winner of poster contest.

The Pelican - Official Line-Up of All Women's International Air Race

A listing of the pilots competing in the All Women's International Air Race, 1953.

Photograph - Percy Band Eating Watermelon Close-up

Black and white photo of Percy Band eating watermelon. This picture is 5 cm x 4 cm.

Parent Prediction of Autism Spectrum Disorder in Infants At Risk: A Follow-up Study

Later-born siblings of children with autism spectrum disorder (ASD) are considered at biological risk for ASD and the broader autism phenotype. Early screening may detect early signs of ASD and facilitate intervention as soon as possible. This follow-up study revisits and re-examines a second-degree autism screener for children at biological risk of autism, the Parent Observation Early Markers Scale (POEMS, Feldman et al., 2012). Using available follow-up information, 110 children (the original 108 infants plus 2 infants recruited after the completion of the original study) were divided into three groups: diagnosed group (n = 13), lost diagnosis group (n = 5), and undiagnosed group (n = 92). The POEMS continued to show acceptable predictive validity. The POEMS total scores and mean number of elevated items were significantly higher in the diagnosed group than the undiagnosed group. The lost diagnosis group did not differ from the undiagnosed group on POEMS total scores and elevated items at any age, but the lost diagnosis group had significantly lower total scores and number of elevated items than the diagnosed group starting at 18 months. Both ASD core and subsidiary behaviours differentiated the diagnosed and undiagnosed groups from 9−36 months of age. Using 70 as a cut-off score, sensitivity, specificity, and positive predictive value (PPV) were .69, .84, and .38, respectively. The study provides further evidence that the POEMS may serve as a low-cost early screener for ASD in at risk children and pinpoint specific developmental and behavioural problems that may be amenable to very early intervention.

Letter to S.D. Woodruff stating that Mr. Mater wishes to take up his mortgage signed Jarvis, Conklin and Co

Letter (1 page, typed) to S.D. Woodruff stating that Mr. Mater wishes to take up his mortgage. It is signed Jarvis, Conklin and Co., Aug. 18, 1884.

Blocking Top-down awareness of Kanizsa Figures: An ERP Investigation into Bottom-up Processing of Illusory Contours

Neural models of the processing of illusory contour (ICs) diverge from one another in terms of their emphasis on bottom-up versus top-down constituents. The current study uses a dichoptic fusion paradigm to block top-down awareness of ICs in order to examine possible bottom-up effects. Group results indicate that the N170 ERP component is particularly sensitive to ICs at central occipital sites when top-down awareness of the stimulus is permitted. Furthermore, single-subject statistics reveal that the IC N170 ERP effect is highly variable across individuals in terms of timing and topographical spread. The results suggest that the ubiquitous N170 effect to ICs found in the literature depends, at least in part, on participants’ awareness of the stimulus. Therefore a strong bottom-up model of IC processing at the time of the N170 is unlikely.

Voucher from the Engineer Department of Port Dalhousie and Thorold Railway Extension for W.G. Thompson for the Northern Division. There are attached notes from the Welland Railway Company to John Mitchell for putting up shelves; to William Waud, staff; and to William Martin to repair the office (copy), June 10, 1857

Voucher from the Engineer Department of Port Dalhousie and Thorold Railway Extension for W.G. Thompson for the Northern Division. There are attached notes from the Welland Railway Company to John Mitchell for putting up shelves; to William Waud, staff; and to William Martin to repair the office (copy), June 10, 1857.

Voucher #22 to James McCoppen (copy) which includes a letter from James McCoppen regarding a claim for having water backed up into his grain and grass by the embankment of the railroad. The letter is dated June 24, 1857 and the voucher is dated Jul. 1, 1857

Voucher #22 to James McCoppen (copy) which includes a letter from James McCoppen regarding a claim for having water backed up into his grain and grass by the embankment of the railroad. The letter is dated June 24, 1857 and the voucher is dated Jul. 1, 1857.

Letter to S.D. Woodruff from George H. Gillespie regarding setting up a meeting of the members of the Long Point Company

Letter to S.D. Woodruff from George H. Gillespie regarding setting up a meeting of the members of the Long Point Company, Dec. 21, 1866.

Letter to S.D. Woodruff from John I. Mackenzie saying that he is closing up the commissariat accounts at Long Point

Letter to S.D. Woodruff from John I. Mackenzie saying that he is closing up the commissariat accounts at Long Point. There is still an amount outstanding and he asks Mr. Woodruff to send a cheque. He hopes that Mr. Woodruff had a good time at Long Point (2 pages, handwritten), Nov. 23, 1881.

Totals of free goods up – class 3 and class 4

Totals of free goods up – class 3 and class 4 (1 page, handwritten), n.d.

7-Up Radio ad with Eartha Kitt

A one minute radio advertising for the soft drink 7-Up featuring the voice of Eartha Kitt.

How to measure the intensity of competition : the mark-up estates for turkish manufacturing industries.

Rapport de recherche

Speak english, little chats a help to learn conversational english,drawn up after the new method of teaching

UANL