Effects of reinforcement rate and delay on the acquisition of lever pressing by rats.

The acquisition of lever pressing by naive rats, in the absence of shaping, was studied as a function of different rates and unsignaled delays of reinforcement. Groups of 3 rats were each exposed to tandem schedules that differed in either the first or the second component. First-component schedules were either continuous reinforcement or random-interval 15, 30, 60 or 120 s; second-component schedules were fixed-time 0, 1, 3, 6, 12, or 24 s. Rate of responding was low under continuous immediate reinforcement and higher under random-interval 15 s. Random interval 30-s and 60-s schedules produced lower rates that were similar to each other. Random-interval 120 s controlled the lowest rate in the immediate-reinforcement condition. Adding a constant 12-s delay to each of the first-component schedule parameters controlled lower response rates that did not vary systematically with reinforcement rate. The continuous and random-interval 60-s schedules of immediate reinforcement controlled higher global and first-component response rates than did the same schedules combined with longer delays, and first-component rates showed some graded effects of delay duration. In addition, the same schedules controlled higher second-component response rates in combination with a 1-s delay than in combination with longer delays. These results were related to those from previous studies on acquisition with delayed reinforcement as well as to those from similar reinforcement procedures used during steady-state responding.     

Protein-binding assays for adrenocorticoids

The measurement of the adrenocortical hormones, Cortisol and corticosterone, m blood plasma has previously best been done by procedures employing varying degrees of purification of the hormone, followed by photometric or fluorimetric quantitation. These methods have been relatively difficult or laborious, particularly in the case of the procedures that most specifically measure the hormoneof intent. These limitations are considerably overcome by new assays for Cortisol and corticosterone based on the principle of competitive protein-binding of the steroids in the presence of radioactively labeled steroid of the same molecular species. These methods are described and data on the specificity of such a method for corticosterone are presented and compared with one of the better fluorimetric assays.     

The Oedipus complex: A confrontation at the central cross‐roads of psychoanalysis

The theory of the Oedipus complex as Freud formulated it rests on the following pillars: the child's characteristic sexual and aggressive impulses concerning the parents, phallic monism, and the castration complex. This paper reviews the context in which Freud discovered the Oedipus complex, as well as Freud's theory. It then examines the proposals of later authors whose general Oedipal theories differ from Freud's in an attempt to point out both their possible correlations and confrontations with Freud. It includes Klein's pre‐genital Oedipal theory, Lacan's structuralist reinterpretation, Bion's reconception of the complex under the knowledge vertex, Green's generalized triangulation theory, Meltzer's notions of the aesthetic object and sexual mental states, and Chasseguet‐Smirgel's archaic Oedipal matrix     

A visual object segmentation algorithm with spatial and temporal coherence inspired by the architecture of the visual cortex

Cognitive Processing - Scene analysis in video sequences is a complex task for a computer vision system. Several schemes have been addressed in this analysis, such as deep learning networks or...     

A cultural adaptation of motivational interviewing to address heavy drinking among Hispanics

Although the need for cultural adaptations is often noted in addiction research, there are few templates to guide the process. The rationale for a social contextual framework to culturally adapt motivational interviewing for an immigrant heavy drinking Latino population in the U.S. Northeast is presented. The aim of the pilot study was to obtain data on acceptability of this approach. Participant responses to the adaptation were examined qualitatively and quantitatively in a preliminary study. Participants recruited from the community met criteria for risky drinking (men, ≥5 drinks/occasion or ≥14 drinks/week; women, ≥4 drinks/occasion or ≥7 drinks/week). Participants (n = 25) who completed baseline assessments and a culturally adapted brief motivational interview (CAMI) were asked to complete a qualitative exit interview to give feedback on their interview experience. Participants reported being highly engaged with treatment (M = 3.58 on a scale of 1-4, SD = .50), and felt very satisfied with treatment (M = 3.58 on a scale of 1-4, SD = .93). Nearly all (95%) reported that understanding their culture was important to understanding their drinking behavior. Results support the acceptability and relevance of this adaptation from participants' perspectives.     

Association between dyads and correct responses on the Paced Auditory Serial Addition Task (PASAT)

The sensitivity of the Paced Auditory Serial Addition Task (PASAT) to working memory deficits may be enhanced by examining "dyads" (i.e., correct responses immediately preceded by a correct response) as a complement to the traditional total correct summary score. In a sample of 397 mostly African American (79%) healthy adults, total dyad and total correct scores were highly correlated (r = .96, p < .001); however, the magnitude of this association diminished in faster stimulus presentation trials, particularly among participants with impaired working memory abilities.     

Ultra-precise quantal timing: Evidence from simultaneity thresholds in long-range apparent movement

Conditions for the disappearance of long-range apparent movement were investigated. In an experiment on beta motion, critical interstimulus intervals (ISIs) of downward simultaneity thresholds for stimuli presented in continuous alternation were determined for exposure durations (EDs) varying from 3 to 160 msec. Each subject performed each test twice. Data were collected in three sessions, each for one of three angular separations (3°, 6°, and 12°) and the full set of EDs. The distribution of critical ISIs collapsed across subjects, EDs, and angular separations shows sharp maxima at regular distances within a range of 0–110 msec ISI. Significant or near-significant peaks were found at ISIs of 5, 9,22,27, 43, 55, and 107 msec. Although mean critical ISIs shifted with spatial separation, no essential shift of the main maxima occurred. Evidence of a periodic modulation with a period duration of 4.5 msec was obtained from the distributions of differences between critical ISIs of the first tests and their replications, which exhibit extremely low standard deviations (< 10 msec). These results agree well with previous analyses (Geissler, 1987, 1992) that led to a taxonomic model of quantal timing, briefly summarized in this paper. Further consequences are discussed and related to earlier developments (Geissler, 1991, 1992,1997).     

Investigating goal conflict as a source of mixed emotions

This research investigated whether (1) the experience of mixed emotions is a consequence of activating conflicting goals and (2) mixed emotions are distinct from emotional conflict. A preliminary experiment (Study 1, N = 35) showed that an elicited goal conflict predicted more mixed emotions than a condition where the same goals were not in conflict. The second experiment was based on naturally occurring goal activation (Study 2, N = 57). This illustrated that mixed emotions were experienced more following conflicting goals compared with a facilitating goals condition—on both a direct self-report measure of mixed emotions and a minimum index measure. The results also showed that mixed emotions were different to emotional conflict. Overall, goal conflict was found to be a source of mixed emotions, and it is feasible that such states have a role in resolving personal dilemmas.