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131.
A dynamic developmental theory of attention-deficit/hyperactivity disorder (ADHD) predominantly hyperactive/impulsive and combined subtypes 总被引:12,自引:0,他引:12
Sagvolden T Johansen EB Aase H Russell VA 《The Behavioral and brain sciences》2005,28(3):397-419; discussion 419-68
Attention-deficit/hyperactivity disorder (ADHD) is currently defined as a cognitive/behavioral developmental disorder where all clinical criteria are behavioral. Inattentiveness, overactivity, and impulsiveness are presently regarded as the main clinical symptoms. The dynamic developmental behavioral theory is based on the hypothesis that altered dopaminergic function plays a pivotal role by failing to modulate nondopaminergic (primarily glutamate and GABA) signal transmission appropriately. A hypofunctioning mesolimbic dopamine branch produces altered reinforcement of behavior and deficient extinction of previously reinforced behavior. This gives rise to delay aversion, development of hyperactivity in novel situations, impulsiveness, deficient sustained attention, increased behavioral variability, and failure to "inhibit" responses ("disinhibition"). A hypofunctioning mesocortical dopamine branch will cause attention response deficiencies (deficient orienting responses, impaired saccadic eye movements, and poorer attention responses toward a target) and poor behavioral planning (poor executive functions). A hypofunctioning nigrostriatal dopamine branch will cause impaired modulation of motor functions and deficient nondeclarative habit learning and memory. These impairments will give rise to apparent developmental delay, clumsiness, neurological "soft signs," and a "failure to inhibit" responses when quick reactions are required. Hypofunctioning dopamine branches represent the main individual predispositions in the present theory. The theory predicts that behavior and symptoms in ADHD result from the interplay between individual predispositions and the surroundings. The exact ADHD symptoms at a particular time in life will vary and be influenced by factors having positive or negative effects on symptom development. Altered or deficient learning and motor functions will produce special needs for optimal parenting and societal styles. Medication will to some degree normalize the underlying dopamine dysfunction and reduce the special needs of these children. The theory describes how individual predispositions interact with these conditions to produce behavioral, emotional, and cognitive effects that can turn into relatively stable behavioral patterns. 相似文献
132.
Although hypochondriasis is associated with the costly use of unnecessary medical resources, this mental health problem remains largely neglected. A lack of clear conceptual models and valid measures has impeded accurate assessment and hindered progress. The Multidimensional Inventory of Hypochondriacal Traits (MIHT) addresses these deficiencies with scales that correspond to a 4-factor model. The MIHT was built with construct validity as a guiding principle and began with an item pool that broadly assessed dimensions identified in the literature. The items were administered to large samples; factor analyses of the responses led to item pool revisions and scale refinements. Multiple studies validated the final MIHT scales and 4-factor model; these findings suggest that the MIHT will contribute to theory and research. 相似文献
133.
The category inclusion rule specifies that categories inherit the properties of their superordinates. For example, given thatall metals are pentavalent, it can be concluded thatall iron is pentavalent. Sloman (1998) showed that people do not fully endorse conclusions that follow from the category inclusion rule. He claims
that people rely on the similarity between the premise and the conclusion categories (metals andiron), rather than applying the category inclusion rule. By allowing reasoners to rate their certainty for category relations
(e.g.,iron is metal), as well as for conclusions, the present study shows that similarity has only an indirect effect on the certainty of conclusions:
Reasoners are more certain that similar categories have a category inclusion relation, and this in turn affects the certainty
of conclusions based on this relation. 相似文献
134.
Russell JL Braccini S Buehler N Kachin MJ Schapiro SJ Hopkins WD 《Animal cognition》2005,8(4):263-272
Studies of great apes have revealed that they use manual gestures and other signals to communicate about distal objects. There is also evidence that chimpanzees modify the types of communicative signals they use depending on the attentional state of a human communicative partner. The majority of previous studies have involved chimpanzees requesting food items from a human experimenter. Here, these same communicative behaviors are reported in chimpanzees requesting a tool from a human observer. In this study, captive chimpanzees were found to gesture, vocalize, and display more often when the experimenter had a tool than when she did not. It was also found that chimpanzees responded differentially based on the attentional state of a human experimenter, and when given the wrong tool persisted in their communicative efforts. Implications for the referential and intentional nature of chimpanzee communicative signaling are discussed. 相似文献
135.
Bruce Russell 《Erkenntnis》2004,61(2-3):245-255
Contextualists often argue from examples where it seems true to say in one context that a person knows something but not true to say that in another context where skeptical hypotheses have been introduced. The skeptical hypotheses can be moderate, simply mentioning what might be the case or raising questions about what a person is certain of, or radical, where scenarios about demon worlds, brains in vats, The Matrix, etc., are introduced. I argue that the introduction of these skeptical hypotheses leads people to fallaciously infer that it is no longer true to say that the relevant person knows. I believe that that is a better explanation of the so-called intuition that the person does not know than the contextualists who claim that raising these skeptical hypotheses changes the standards that determine when it is true to say S knows that P. At the end I raise the possibility that contextualists might defend their view on pragmatic rather than skeptical grounds by arguing that the standards of evidence rise when more is at stake in a practical sense. 相似文献
136.
Spears R Gordijn E Dijksterhuis A Stapel DA 《Personality & social psychology bulletin》2004,30(5):605-616
Whereas previous research has shown automatic behavior conforming to outgroup stereotypes, the authors demonstrate automatic behavioral contrast away from a stereotype/trait associated with an outgroup (Study 1 and 2) and point to the importance of an "us-them" intergroup comparison in this process. In Study 1, participants colored pictures more messily when neatness was associated with an outgroup rather than the ingroup. In Study 2, using a different behavior, participants primed with busy business people reacted faster than controls (assimilation) but became slower when their student ingroup identity was activated (contrast). Subliminally priming an "us-them" intergroup comparison set undermined the accessibility of outgroup stereotypic words (Study 3), especially for those higher in prejudice (Study 4). This suggests that people automatically distance themselves from outgroup attributes when intergroup antagonism is cued or chronic. Implications for the role of self and comparison processes in automatic behavior are discussed. 相似文献
137.
Throughout the U.S., state laws require professionals who work with children to report cases of suspected child abuse to child protection services. Both practically and conceptually, however, significant problems arise from a lack of clarity regarding the threshold that has been set for reporting. Specifically, there is no consensus as to what constitutes reasonable suspicion, and little direction for how mandated reporters should gauge their legal and professional responsibilities when they harbor suspicion. In this paper we outline the context of the problem, discuss the nature and scope of its conceptual underpinnings, and offer recommendations for moving towards a concrete, practical solution. 相似文献
138.
An ongoing assumption made by sleep researchers is that since dreams are more often recalled on awakening from rapid eye movement (REM) sleep, dreams must occur more often during this stage of sleep. An alternative hypothesis is that cognition occurs throughout sleep, but the recall of this mentation differs on awakening. When a dream is not reported on awakening, there is no method of establishing whether it did not happen or was forgotten. The aim of the present study was to investigate this issue using an eye movement (EM) signal verification technique. Participants were instructed to produce an EM signal whenever they heard a tone. Tones were presented at increasing volume during Stage 2 and REM sleep until EM signal verification was observed. Ninety seconds after signal verification, participants were awakened and asked if they remembered hearing the tone or responding with the EM signal. Such recollection of signal verified tone (SVT) presentations was significantly less after Stage 2 sleep (65%) compared to REM sleep (100%) presentations. Furthermore, SVT recall was significantly correlated with reported dream recall frequency, suggesting the same processes involved in recalling SVTs might also underlie dream recall. 相似文献
139.
Studies of human classification learning using functional neuroimaging have suggested that basal ganglia and medial temporal lobe memory systems may interact during learning. We review these results and outline a set of possible mechanisms for such interactions. Effective connectivity analyses suggest that interaction between basal ganglia and medial temporal lobe are mediated by prefrontal cortex rather than by direct connectivity between regions. A review of possible neurobiological mechanisms suggests that interactions may be driven by neuromodulatory systems in addition to mediation by interaction of inputs to prefrontal cortical neurons. These results suggest that memory system interactions may reflect multiple mechanisms that combine to optimize behavior based on experience. 相似文献
140.
Catalano GD 《Science and engineering ethics》2004,10(2):409-415
A senior level capstone design experience has been developed and offered with a particular emphasis on many of the professional
issues raised in Accreditation Board for Engineering and Technology (ABET) Engineering Criterion IV. The course has sought
to develop student awareness of the ethical foundation of the engineering profession, the global and societal framework within
which engineers practice, and the environmental impact on engineering. The capstone design course also focused upon improving
the technical communications skills of the graduating senior class with both extensive instruction in writing and multiple
workshops dealing with the art of making an effective oral presentation. The effectiveness of the design course was assessed
using Kirkpatrick’s model for evaluating training programs.
An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting,
New Orleans, 2003. 相似文献