Manodepressive disorders: a theory based on a neurophysiological model.

T Johannisson

doi:10.1016/0306-9877(93)90077-4

Home/Archive/PubMed

PubMed · 8289697

Manodepressive disorders: a theory based on a neurophysiological model.

T Johannisson

View original source ↗Export metadata ↓

Abstract

In a previously presented model, a column in the cerebral cortex has activity at two separate levels. A few columns are under normal conditions at the high level of activity at a time while the rest are kept at the low level. The effects of changes in the number of columns that are at the high level of activity simultaneously have been dealt with in previous papers. It has been concluded that a somewhat increased number results in positive schizophrenic symptoms, and that too few can give negative schizophrenic symptoms. In the present paper, the effects of changes in a second parameter are discussed. This parameter is the length of time during which a cerebral column is at the high level of activity. It is explained how too short duration causes the manic phase in manodepressive disorders, and too long duration the depressive phase.

Explore related subjects

Association Bipolar Disorder Cerebral Cortex Delirium Humans Models, Neurological Models, Psychological Thinking Time Factors Journal Article

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

T Johannisson. 1993. Manodepressive disorders: a theory based on a neurophysiological model.. https://doi.org/10.1016/0306-9877(93)90077-4

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Representing word meaning and order information in a composite holographic lexicon.

The authors present a computational model that builds a holographic lexicon representing both word meaning and word order from unsupervised experience with natural language. The model uses simple convolution and superposition mechanisms (cf. B. B. Murdock, 1982) to learn distributed holographic representations for words. The structure of the resulting lexicon can account for empirical data from classic experiments studying semantic typicality, categorization, priming, and semantic constraint in sentence completions. Furthermore, order information can be retrieved from the holographic representations, allowing the model to account for limited word transitions without the need for built-in transition rules. The model demonstrates that a broad range of psychological data can be accounted for directly from the structure of lexical representations learned in this way, without the need for complexity to be built into either the processing mechanisms or the representations. The holographic representations are an appropriate knowledge representation to be used by higher order models of language comprehension, relieving the complexity required at the higher level.

Association↗

PubMed2007

Separating bias and sensitivity in judgments of associative memory.

Ratings of the degree of association between words are linearly related to normed associative strengths, but the intercept is high, and the slope is shallow (the judgments of associative memory [JAM] function). Two experiments included manipulations intended to decrease the intercept and increase the slope. Discrimination training on many pairs of words and constraining ratings to sum to a constant both reduced the intercept but failed to change the slope. The intercept of the JAM function appears to contain a bias component that can be manipulated independently of the slope, which reflects sensitivity to associative strengths.

Association↗

PubMed2007

Transfer of noncorresponding spatial associations to the auditory Simon task.

Four experiments examined transfer of noncorresponding spatial stimulus-response associations to an auditory Simon task for which stimulus location was irrelevant. Experiment 1 established that, for a horizontal auditory Simon task, transfer of spatial associations occurs after 300 trials of practice with an incompatible mapping of auditory stimuli to keypress responses. Experiments 2-4 examined transfer effects within the auditory modality when the stimuli and responses were varied along vertical and horizontal dimensions. Transfer occurred when the stimuli and responses were arrayed along the same dimension in practice and transfer but not when they were arrayed along orthogonal dimensions. These findings indicate that prior task-defined associations have less influence on the auditory Simon effect than on the visual Simon effect, possibly because of the stronger tendency for an auditory stimulus to activate its corresponding response.

Association↗