{"title":"The monoaminergic innervation of primate neocortex.","authors":"D A Lewis, M J Campbell, S L Foote, J H Morrison","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In brain, the monoamines, dopamine, norepinephrine, and serotonin, are confined to anatomically distinct neuronal systems, each of which furnishes widespread projections to neocortex. In primate, but not in rat, the terminal patterns of each of these systems have a high degree of regional and laminar specificity. These findings suggest that there are different sites of action and possibly different functional roles for each of the monoamines. This type of precise anatomic information is essential to our understanding of the possible involvement of monoamines in human disease states.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 3","pages":"181-8"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14656841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Neurotransmitter deficits in Alzheimer's disease and in other dementing disorders.","authors":"D M Mann, P O Yates","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The evidence for deficiencies in neurotransmitters in Alzheimer's disease is reviewed. Major losses occur in the subcortical afferent projection systems based on acetylcholine, noradrenaline and serotonin. Within the cortex, somatostatin containing neurones and the large pyramidal cells, presumed to use glutamate/aspartate as transmitters, are the most severely damaged cells. The anatomical distribution of cell loss is explainable if the primary site of damage lies within the cortex; nerve cells are damaged by virtue of their presence within or their connections to this region. The senile plaque may represent the site of this damage and neurofibrillary tangle formation and accumulation may lead to cell death. In patients with Down's syndrome who live past 40 years, changes in transmitters apparently identical to those in Alzheimer's disease occur. The dementia of Parkinson's disease appears related to damage to cholinergic, noradrenergic and dopaminergic systems and may reflect a failure of these subcortical regions to sufficiently \"activate\" an otherwise undamaged cortex.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 3","pages":"147-58"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14012662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Neural dynamics of speech and language coding: developmental programs, perceptual grouping, and competition for short-term memory.","authors":"M Cohen, S Grossberg","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A computational theory of how an observer parses a speech stream into context-sensitive language representations is described. It is shown how temporal lists of events can be chunked into unitized representations, how perceptual groupings of past item sublists can be reorganized due to information carried by newly occurring items, and how item information and temporal order information are bound together into context-sensitive codes. These language units are emergent properties due to intercellular interactions among large numbers of nerve cells. The controlling neural networks can arise through simple rules of neuronal development: random growth of connections along spatial gradients, activity-dependent self-similar cell growth, and competition for conserved synaptic sites. Within these networks, a spatial frequency analysis of temporally evolving activity patterns leads to competitive masking of inappropriate list encodings in short term memory. The neurons obey membrane equations undergoing shunting recurrent on-center off-surround interactions. Several design principles are embodied by the networks, such as the sequence masking principle, the long-term memory invariance principle, and the principle of self-similar growth.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 1","pages":"1-22"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14638985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Computing and understanding.","authors":"P C Dodwell","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 2","pages":"137-44"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14852322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Interhemispheric transmission delays in human strabismics.","authors":"R St John, B Timney","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Experimentally induced strabismus in cats and monkeys leads to a variety of anatomical, physiological, and perceptual deficits. Given the similarities between the perceptual deficits of human strabismics and those of animal models, it is reasonable to suggest similarities in the underlying anatomical and physiological deficits. In cat, one anatomic anomaly associated with strabismus is a disruption of the normal development of the posterior corpus callosum. The present study provides evidence that interhemispheric transmission in human strabismics may be disrupted also. Simple unimanual reaction times were used to examine the transmission of information through callosal fibres. Estimates of cross-callosal transmission time for strabismics were consistently longer than for individuals with no history of strabismus. This difference was found only when targets were presented within 5 degrees of the fixation point. The results suggest that human strabismics may have abnormalities in those callosal fibres which are involved in the interhemispheric transmission of visual information.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 2","pages":"97-103"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14149549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Handedness, footedness and finger and toe movement-related cerebral potentials.","authors":"J Boschert, L Deecke","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Sixteen right-handed and 16 left-handed subjects were compared with respect to their foot dominance and the topography of their pre-movement cerebral potentials (Bereitschaftspotential, BP). First, righthanders were usually also found to be right-footed. Lefthanders showed a similar trend in preferring their left foot. Second, the BP prior to volitional self-paced movements of fingers and toes on either side was examined. For finger movements, the BP always showed higher amplitudes over the contralateral hemisphere as compared to the ipsilateral one (contralateral preponderance of negativity, CPN). For toe movements a significant ipsilateral preponderance of negativity (IPN) occurred in all subjects. The CPN was larger for finger movements of the dominant hand than it was for finger movements on the non-dominant side. By contrast, the IPN was larger prior to movements of the \"non-dominant toes\" than it was for movements of the dominant toes. This can be explained by assuming that the hemisphere contralateral to the dominant hand, generates more negativity than the one contralateral to the non-dominant hand. This assumption is further discussed in the context of a vector model for the BP.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 4","pages":"235-43"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14936180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Patterns of stimulus- and self-induced slow brain potentials--a sign of task-specific preparation.","authors":"T Elbert","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Does the scalp distribution of slow shifts in human brain potentials depend upon the processing demands? The question was approached applying two different paradigms. In the first study, the anticipation of haptic tasks presented to either of the hands was found to give rise to a contralateral slow negative brain potential (SP). The second study demonstrated that comparable hemisphere-specific patterns can be self-induced by means of biofeedback training. These results suggest that negative SPs (like the CNV) indicate preactivation of those brain-regions that process the expected task.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 1","pages":"67-9"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14819855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Visually and auditory evoked EEG potentials in carriers of four hereditary EEG variants.","authors":"F Vogel, J Krüger, H P Höpp, E Schalt, R Schnobel","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Visually and auditory evoked EEG potentials were studied in 248 healthy university students, who were carriers of one of the following hereditary EEG variants: Monomorphic alpha-waves; low-voltage-EEG; EEG in which the alpha-rhythm was mixed diffusely with beta-waves; and EEG with fronto-precentral beta-groups. The study uncovered consistent and statistically significant group differences between the EEG-countertypes, monomorphic alpha-waves and the low-voltage EEG: subjects with monomorphic alpha-waves showed higher amplitudes and longer latencies of most peaks of the visually evoked potential (VEP), and higher amplitudes for most peaks of the auditory evoked potentials (AEP). Similar differences between EEG types were shown for two measures--overall amplitude (oscillation) and average latency--of all peaks for VEPs and AEPs. The results are consistent with a hypothesis discussed in an earlier paper in which differences between these two EEG types in processing of information in the CNS were assumed on the basis of psychological test results and neurophysiological theory. The two EEG types with beta-waves in addition to alpha-waves showed latencies of evoked potentials in-between those found in the EEG types with monomorphic alpha-waves, on the one hand, and the low-voltage EEG on the other. There was no significant difference in the frequency of VEP augmenters and reducers between EEG types.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 1","pages":"49-58"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14819880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the discrimination of micropatterns and textures.","authors":"T Caelli, M Hübner, I Rentschler","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The Perceptron-type of approach of texture perception argues for decomposition of the patterns by detectors or filters which can interact to result in classification of spatial information. We consider a case of texture discrimination where textures composed of discriminable grey-level micropatterns may or may not be distinguished. Two types of models involving linear pattern decomposition are shown to be insufficient for explaining such results. This suggests that observers encode the signals by means of signal dependent or adaptive feature extractors. Such a concept of texture perception is related to connectionist ideas of information processing as pursued by Julesz in his texton theory.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 2","pages":"129-36"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14852321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Early development of tyrosine hydroxylase-like and substance P-like immunoreactivity in the human fetal retina.","authors":"J Nguyen-Legros, C Versaux-Botteri, A Vigny","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Tyrosine hydroxylase-(TH)-like and Substance-P-(SP)-like immunoreactivity has been tentatively located in the retina of 24-29 week-old fetuses, newborn infants, 2-8-month-old children, and adults. The first TH immunoreactive cells were demonstrated as early as 24 weeks of fetal life, while SP immunoreactivity appeared a little later, between 24 and 29 weeks. Thus the period ranging between 24 and 29 weeks of fetal life is considered to be important in the establishment of transmitter specific characteristics in human retinal neurons.</p>","PeriodicalId":77724,"journal":{"name":"Human neurobiology","volume":"5 2","pages":"115-20"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13574728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}