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1.
Pigeons trained on successive AB symbolic matching show emergent BA antisymmetry if they are also trained on successive AA oddity and BB identity ( Urcuioli, 2008 , Experiment 4). In other words, when tested on BA probe trials following training, they respond more to the comparisons on the reverse of the nonreinforced AB baseline trials than on the reverse of the reinforced AB baseline trials (the opposite of an associative symmetry pattern). The present experiment replicated this finding. In addition, it showed that antisymmetry also emerged after baseline training on successive AB symbolic matching, AA identity, and BB oddity, consistent with the prediction from Urcuioli's (2008) theory of pigeons' stimulus‐class formation. Together, these results provide further empirical support for that theory including the proposition that the functional stimuli in pigeons' successive matching consist of the nominal stimuli plus their ordinal positions within a trial.  相似文献   

2.
孙天义  肖鑫  郭春彦 《心理学报》2008,40(5):562-570
采用ERP探究在预知条件下任务转换的神经机制。使用“任务转换”实验范式,以汉字(名词/动词)或数字(奇数/偶数)的归类为任务。被试执行任务重复(AA,BB,…)或在两个任务间转换(AB,BA,…),每个任务序列为连续的两个任务(任务1,任务2)。结果发现,任务1中,在刺激呈现后300ms左右,数、词的转换序列与重复序列出现显著差异;在中央区,320ms左右,任务1中转换序列比重复序列、任务2中转换任务比重复任务都产生一个更为负走向的波。这些结果表明,在预知条件下,简单任务转换的内源性准备可能开始于任务1呈现后300ms左右;内源性准备和外源性调节可能都反映了认知冲突过程,此认知冲突可能是转换代价的主要来源  相似文献   

3.
In this article, we explore the neural correlates of the general and specific factors assessed by the Life Orientation Test–Revised. These factors have been shown to assess general optimism (GO) and a form of self-enhancement akin to unrealistic optimism (SP). Toward our aim, we used a standardized low-resolution brain electromagnetic tomography (sLORETA), which provides electroencephalographic (EEG) localization measures that are independent of recording reference. Resting-EEG and self-report measures of GO and SP were collected from 51 female undergraduates. EEGs were recorded across 29 scalp sites. Anterior and posterior source alpha asymmetries of cortical activation were obtained by using the sLORETA method. On the basis of previous research findings, ten frontal and six parietal regions of interest (ROIs) were derived. Alpha asymmetry in the posterior cingulate (i.e., BA31) was uniquely associated with GO. In contrast, SP was associated with areas of the inferior frontal gyrus (BA44, BA45) and with the left subcentralis area (BA43). Theoretical and practical implications of the findings are provided and discussed.  相似文献   

4.
Behavioral activation (BA) is a well-supported treatment approach, but little research has been conducted on the effectiveness of this treatment within publicly funded community mental health settings. We examined the feasibility of conducting a randomized trial examining the effectiveness of nine sessions of BA as a treatment for major depressive disorder (MDD) in a community mental health clinic (CMHC) setting. Following adaptation of a BA manual and training of BA therapists, 80 patients seeking treatment at a CMHC were randomized, with a 3:1 randomization rate of BA to nine sessions of treatment as usual (TAU). Feasibility assessments indicated that only one eligible patient refused randomization and, of patients who attended at least one session, the median number of sessions was six for the BA group and eight for the TAU group. Of three postbaseline monthly assessments, 71.3% (171/240) were successfully obtained. On average, patients in the BA condition completed homework assignments 83.9% of the time. Treatment fidelity ratings indicated that substantially more BA techniques were delivered in the BA group compared to the TAU group (d = 2.11). Measures of BA mechanisms improved significantly over time and these changes were significantly associated with change in depressive symptoms. These results indicate that it is feasible to conduct a randomized study of BA for MDD in a CMHC setting. In addition, the study reconfirmed the potential importance of theory-relevant BA mechanism variables. Following these findings, further investigation into the effectiveness of BA in this setting is needed.  相似文献   

5.
Four adult right-handed chronic stutterers and four age-matched controls completed H(2)(15)O PET scans involving overt and imagined oral reading tasks. During overt stuttered speech prominent activations occurred in SMA (medial), BA 46 (right), anterior insula (bilateral), and cerebellum (bilateral) plus deactivations in right A2 (BA 21/22). These activations and deactivations also occurred when the same stutterers imagined they were stuttering. Some parietal regions were significantly activated during imagined stuttering, but not during overt stuttering. Most regional activations changed in the same direction when overt stuttering ceased (during chorus reading) and when subjects imagined that they were not stuttering (also during chorus reading). Controls displayed fewer similarities between regional activations and deactivations during actual and imagined oral reading. Thus overt stuttering appears not to be a prerequisite for the prominent regional activations and deactivations associated with stuttering.  相似文献   

6.
This study tested the notion that an equivalence relation may include a response when differential responses are paired with stimuli presented during training. Eight normal adults learned three kinds of computer mouse movements as differential response topographies (R1, R2, and R3). Next, in matching-to-sample training, one of the response topographies was used to select a comparison stimulus B (B1, B2, or B3) conditionally upon presentation of sample stimulus A (A1, A2, or A3), and to select stimulus D (D1, D2, or D3) conditionally upon presentation of stimulus C (C1, C2, or C3). After two sample-comparison-response relations (ABR and CDR) were established, 18 sample-comparison relations were tested (BA, DC, RA, RB, RC, RD, AC, CA, AD, DA, BC, CB, BD, DB, AA, BB, CC, and DD). In the RA, RB, RC, and RD tests, the differential responses (R1, R2, and R3) were used as sample stimuli. All subjects made class-consistent comparison selections in the tests. This study provides evidence that responses may become members of an equivalence class.  相似文献   

7.
Two experiments evaluated the ability of younger and older adults to visually discriminate 3-D shape as a function of surface coherence. The coherence was manipulated by embedding the 3-D surfaces in volumetric noise (e.g., for a 55?% coherent surface, 55?% of the stimulus points fell on a 3-D surface, while 45?% of the points occupied random locations within the same volume of space). The 3-D surfaces were defined by static binocular disparity, dynamic binocular disparity, and motion. The results of both experiments demonstrated significant effects of age: Older adults required more coherence (tolerated volumetric noise less) for reliable shape discrimination than did younger adults. Motion-defined and static-binocular-disparity-defined surfaces resulted in similar coherence thresholds. However, performance for dynamic-binocular-disparity-defined surfaces was superior (i.e., the observers?? surface coherence thresholds were lowest for these stimuli). The results of both experiments showed that younger and older adults possess considerable tolerance to the disrupting effects of volumetric noise; the observers could reliably discriminate 3-D surface shape even when 45?% of the stimulus points (or more) constituted noise.  相似文献   

8.
During adolescence, cognitive abilities increase robustly. To search for possible related structural alterations of the cerebral cortex, we measured neuronal soma dimension (NSD = width times height), cortical thickness and neuronal densities in different types of neocortex in post-mortem brains of five 12-16 and five 17-24 year-olds (each 2F, 3M). Using a generalized mixed model analysis, mean normalized NSD comparing the age groups shows layer-specific change for layer 2 (p < .0001) and age-related differences between categorized type of cortex: primary/primary association cortex (BA 1, 3, 4, and 44) shows a generalized increase; higher-order regions (BA 9, 21, 39, and 45) also show increase in layers 2 and 5 but decrease in layers 3, 4, and 6 while limbic/orbital cortex (BA 23, 24, and 47) undergoes minor decrease (BA 1, 3, 4, and 44 vs. BA 9, 21, 39, and 45: p = .036 and BA 1, 3, 4, and 44 vs. BA 23, 24, and 47: p = .004). These data imply the operation of cortical layer- and type-specific processes of growth and regression adding new evidence that the human brain matures during adolescence not only functionally but also structurally.  相似文献   

9.
《Behavior Therapy》2021,52(5):1198-1212
College students with attention-deficit/hyperactivity disorder (ADHD) are at risk for alcohol-related problems and disorders relative to their typically developing peers. Despite risk, the optimal therapeutic approach for reducing problem alcohol use in students with ADHD, and mechanisms of change underlying treatment effects in this population, are largely unknown. The current study evaluated putative mechanisms of change in a randomized controlled trial of two harm reduction interventions for college student drinkers with ADHD (N = 113; 49% male): brief motivational intervention plus supportive counseling (BMI + SC) versus brief motivational intervention plus behavioral activation (BMI + BA). Results showed that participants in the BMI + BA condition engaged in more goal-directed activation and less avoidant behavior over the course of treatment compared to those in the BMI + SC condition, in turn predicting reductions in alcohol-related negative consequences. Effects were more robust 1 month following intervention, and diminished by 3 months. Sensitivity analyses revealed a significant indirect effect of treatment condition on alcohol-related negative consequence via reductions in avoidance over treatment. Post hoc moderated mediations showed that BMI + BA engaged target mechanisms more robustly for students with more severe ADHD and depressive symptoms compared to BMI + SC. These findings support the application of BMI + BA intervention, particularly in targeting goal-directed activation and avoidance/rumination in at-risk student drinkers with ADHD.  相似文献   

10.
利用功能性磁共振成像(fMRI)技术探讨文盲和非文盲汉字字形和语音加工脑机制的差异。实验1使用汉字字形和图形比较了中国人文盲和非文盲字形加工过程脑机制的左侧差异。实验2使用汉字语音和纯音比较了文盲和非文盲语音加工过程脑机制的双侧差异。结果表明文盲与非文盲汉字字形和语音加工脑机制不同,且非文盲的脑活动强。  相似文献   

11.
Exposure and response prevention (ERP) and behavioral activation (BA) are effective treatments for obsessive-compulsive disorder (OCD) and depression, respectively. Patients with OCD often exhibit depression; furthermore, ERP for OCD is associated with reduced depressive symptoms. To our knowledge, no study has examined whether ERP itself functions to behaviorally activate patients with concurrent OCD and depressive symptoms. This prospective study was designed to test the hypotheses that (a) OCD exposure hierarchy completion, increased BA, and depressive symptom reduction would all be related, and (b) pre- to posttreatment changes in BA would mediate the direct effect of OCD hierarchy completion on posttreatment depressive symptoms, even after controlling for pretreatment depressive symptoms, pretreatment BA, pre- to posttreatment reductions in OCD symptoms, treatment duration, and antidepressant medication use. Patients (N = 90) with a primary diagnosis of OCD who received residential ERP for OCD completed a self-report battery at pre- and posttreatment. Exposure hierarchy completion, increases in BA, and decreases in depression were all significantly correlated (rs ranged .33 to .44). The effect of hierarchy completion on posttreatment depressive symptoms was fully mediated by pre- to posttreatment changes in BA. Findings highlight the potential for ERP to exert antidepressant effects by behaviorally activating patients. Limitations, clinical implications, and future directions are discussed.  相似文献   

12.
Using educational attainment to indicate socioeconomic status, the authors examined models of agency and effects of choice among European American adults of different educational backgrounds in 3 studies. Whereas college-educated (BA) participants and their preferred cultural products (i.e., rock music lyrics) emphasized expressing uniqueness, controlling environments, and influencing others, less educated (HS) participants and their preferred cultural products (i.e., country music lyrics) emphasized maintaining integrity, adjusting selves, and resisting influence. Reflecting these models of agency, HS and BA participants differently responded to choice in dissonance and reactance paradigms: BA participants liked chosen objects more than unchosen objects, but choice did not affect HS participants' preferences. Results suggest that HS and BA models of agency qualitatively differ, despite overlap between HS and BA worlds.  相似文献   

13.
This study examined the effects of Behavioral Activation (BA) treatment on depressive symptoms and quality of life among older adult patients in a geriatric psychiatry facility. There were 50 participants with mild to moderate cognitive impairment, each being 65 years of age or older. A 2 (between) × 3 (time of measurement) design was used in this study comparing control (treatment-as-usual) and experimental (BA) conditions at pre-, mid-, and posttreatment. BA consisted of eight 30- to 60-minute sessions across 4 weeks. Intent-to-treat analyses indicated a significant Group × Time interaction on depressive symptoms, with this effect remaining when only completer data were included. Further analyses indicated that this effect was due to significant change early in treatment in both the full and completer samples. There was no evidence of a significant effect on the quality-of-life measure. Cognitive status was not related to change in depressive symptoms, suggesting that BA may be useful across a range of older adults.  相似文献   

14.
The effects of changes in signal-to-noise ratio (SIN) and feedback state on the operator’s detection behavior, particularly derived operator thresholds, were investigated using a discrete visual signal. It was found that: (1) the operator behaves as if he has established different thresholds as a function of S/N; (2) his decision thresholds are relatively independent of the presence or absence of feedback; and (3) the operator will change his threshold accordingly for a change from one S/N to another. A model of the operator’s behavior, which introduced the concept of “operator” noise. yielded predictions of detection and false alarm probabilities which were extremely close to the observed values.  相似文献   

15.
The establishment of sample/S- relations (or reject control) during conditional discrimination training (AB, BC) affects transitivity (AC), equivalence (CA) and reflexivity (AA, BB, CC) test outcomes. The present study parametrically evaluated the effects of different observing patterns to comparison stimuli on the establishment of reject control during baseline conditional relation training. A matching-to-sample with observing requirements (MTS-OR) procedure was implemented during AB and BC conditional discrimination training. During training, the participants were required to observe the sample and incorrect comparison on every trial before responding. In addition, the participants were divided into three groups that differed regarding the percentage of training trials on which they were prevented from observing the correct comparison stimuli: 25%, 50%, and 75%. Once the mastery criteria were achieved during training, transitivity (AC), symmetry (BA, CB), equivalence (CA), and reflexivity (AA, BB, CC) tests were conducted with all comparison stimuli visible from the beginning. The results suggest that the number of errors during transitivity, equivalence, and reflexivity tests progressively increased as participants were prevented from observing the correct comparison on a greater number of trials during training. Symmetry test results, however, were not affected by the experimental manipulation. Moreover, the number of participants showing reject-control patterns during tests slightly increased and the number of participants showing select-control patterns decreased as a function of the number of trials on which the participants were prevented from observing the correct comparison. Thus, we suggest that observing patterns during training is a relevant variable that affects equivalence test outcomes.  相似文献   

16.
One problem of interpreting research on subconscious processing is the possibility that participants are weakly conscious of the stimuli. Here, we compared the fMRI BOLD response in healthy adults to clearly visible single letters (supraliminal presentation) with the response to letters presented in the absence of any behavioural evidence of visibility (subliminal presentation). No letter catch trials served as a control condition. Forced-choice responses did not differ from chance when letter-to-background contrast was low, whereas they were almost 100% correct when contrast was high. A comparison of fMRI BOLD signals for supraliminal and subliminal letters with the control trials revealed a signal increase in left BA 37 (fusiform gyrus). Comparison of supraliminal with subliminal letters showed a significant increase in the right inferior frontal gyrus (BA 44, partly extending to BA 9 and BA 45, as well as BA 46). Finally, a comparison of subliminal with supraliminal letters showed increases in the left middle temporal gyrus (BA 21) and the right extrastriate cortex (BA 19).  相似文献   

17.
Brief-moderate shock (3, 0.75 s, 1.0 mA) has opposite effects on different measures of pain, inducing antinociception on the tail-flick test while lowering vocalization thresholds to shock and heat (hyperalgesia) and enhancing fear conditioned by a gridshock unconditioned stimulus (US). This study examined the generality of shock-induced hyperalgesia under a range of conditions and explored parallels to sensitized startle. Reduced vocalization thresholds to shock and antinociception emerged at a similar shock intensity. Severe shocks (3, 25 s, 1.0 mA or 3, 2 s, 3.0 mA) lowered vocalization threshold to shock but increased vocalization and motor thresholds to heat and undermined fear conditioned by a gridshock or a startling tone US. All shock schedules facilitated startle, but only brief-moderate shock inflated fear conditioning. The findings suggest that brief-moderate shock enhances the affective impact of aversive stimuli, whereas severe shocks attenuate pain.  相似文献   

18.
This set of two studies employed the integrated threat theory to examine attitudes toward affirmative action (AA). The first study found that opposition to the policy of AA was predicted by realistic threats, symbolic threats, and personal relevance; while attitudes toward the beneficiaries of AA were predicted by three of the four threat variables (symbolic threats, intergroup anxiety, and negative stereotypes), and in‐group identity. The second study replicated and expanded on the first study and found that the effects of several individual‐difference variables (racism, anti‐Black affect, and political conservatism) on opposition to AA were mediated by three of the threats in the integrated threat theory (realistic threats, symbolic threats, and negative stereotypes). The implications of the results are discussed.  相似文献   

19.
Although research on the hierarchical model of anxiety and depression has confirmed that autonomic arousability (AA) is more germane to panic disorder with or without agoraphobia (PD/A) than other DSM-IV anxiety and mood disorders, studies have not evaluated the differential relevance of AA to posttraumatic stress disorder (PTSD). This issue was addressed in multivariate analytic models using 295 outpatients with anxiety and mood disorders. Consistent with prediction, the presence of current DSM-IV PTSD and PD/A was significantly predictive of AA, even when other forms of anxiety disorder comorbidity were held constant. Moreover, latent structural analyses indicated that PTSD and PD/A were the only DSM-IV anxiety disorder constructs to have significant direct effects on AA (in accord with previous findings, the DSM-IV constructs of generalized anxiety disorder, social phobia, and obsessive-compulsive disorder did not have significant structural relationships with AA). The current findings, which attest to the specificity of AA to PTSD and PD/A, are discussed in context of other clinically salient shared features of these disorders and their relevance to treatment and diagnostic classification.  相似文献   

20.
《Behavior Therapy》2023,54(3):524-538
There is a striking disparity between the number of individuals with significant mental health concerns and those who are able to access care globally. One promising solution to expanding the mental health taskforce is task-sharing, or employing nonspecialists in the delivery of evidence-based interventions. Behavioral activation (BA), a brief intervention that focuses on scheduling rewarding activities into one’s daily life, may have promise for delivery using task-sharing approaches due to its straightforward, flexible nature. The aim of this systematic review was to examine the current state of the literature on non-specialist-delivered BA and evaluate the evidence base of this approach. Three databases (Pubmed, PsycInfo, and Cochrane) were searched, and all articles were screened for inclusion criteria by two research assistants, included the review of titles, abstracts, and full-text. The final dataset consisted of 13 research studies, represented through 15 articles. A meta-analysis was conducted to examine the overall pooled effects of peer-delivered BA on depressive symptoms (the most widely examined clinical outcome). Studies reported on effectiveness and implementation outcomes of non-specialist-delivered BA for depression, substance use, loneliness, trauma survivors, and individuals with comorbid physical health conditions. Results provide initial support for the effectiveness of BA utilizing a task-sharing approach, and highlight the feasibility and acceptability of using nonspecialists to deliver BA in a variety of contexts, including low-resource settings.  相似文献   

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