| David LaBerge; Attentional Processing | |||||
| Book | Page | Topic | |||
| LaBerge; Attentional Processing | 98 | Attentional Processing in Cortical Areas | |||
| LaBerge; Attentional Processing | 98 | Attention as a modulation of information flow in the brain apparently occurs within the circuits of particular areas, and the control exerted upon this attentional expression is presumed to be communicated along relatively long pathways that interconnect the particular areas. | 0 | ||
| LaBerge; Attentional Processing | 100 | Visual information enters the brain by way of area V1 and a superior colliculus (SC) and flows to areas where specialized processing modules compute various properties of an object or event, such as its location and identity. | 2 | ||
| LaBerge; Attentional Processing | 101 | Thirty-two or so areas of the visual cortex. | 1 | ||
| LaBerge; Attentional Processing | 101 | Processing some property of an object, such as its location, shape, color, depth, and direction of movement. | 0 | ||
| LaBerge; Attentional Processing | 101 | Posterior cortex is structured to compute judgments of particular properties of a stimulus object or scene by segregating the input information and directing it to appropriate sets of structures or modules that perform specialized types of computation. | 0 | ||
| LaBerge; Attentional Processing | 101 | The accumulation of evidence that the visual system contains many separable cortical areas beyond the striate projection area of V1 began with the work of Zeki (1969) in the macaque monkey. | 0 | ||
| LaBerge; Attentional Processing | 104 | Ventral and dorsal cortical processing streams. | 3 | ||
| LaBerge; Attentional Processing | 104 | Two distinct processing streams arise from area V1. | 0 | ||
| LaBerge; Attentional Processing | 104 | The ventral stream (V1 to V2, V1 to V3, V1 to V4) flows ventrally toward the visual areas of the temporal lobe that are necessary for the discrimination, identification, and recognition of objects. | 0 | ||
| LaBerge; Attentional Processing | 104 | The dorsal stream (V1 to V5, V1 to V2) flows toward the visual areas of the parietal lobe that are necessary for spatial perception and visually guided actions. | 0 | ||
| LaBerge; Attentional Processing | 105 | Patterns of interconnectivity between visual cortical areas had been classified in a hierarchical organization of ten levels. | 1 | ||
| LaBerge; Attentional Processing | 106 | A general rule of connectivity between cortical areas is that an area receiving fibers from another area reciprocates the connection. | 1 | ||
| LaBerge; Attentional Processing | 109 | Attention to Object Information in Ventral Cortical Streams | 3 | ||
| LaBerge; Attentional Processing | 109 | Cortical areas specialized in identifying objects include the inferotemporal area (IT), the V4 area, in posterior parietal cortex (PPC), and the dorsolateral prefrontal cortex (DLPFC). | 0 | ||
| LaBerge; Attentional Processing | 109 | Two major parts of the inferotemporal cortex are: (1) the posterior part, which contains a subarea TEO that is specialized for fine discrimination of forms, and (2) an anterior part of the temporal lobe (sometimes labeled TE) which contains the mnemonic properties necessary for identification of an object. | 0 | ||
| LaBerge; Attentional Processing | 110 | The familiarity of an object, important to its recognition, appears to involve the superior temporal polysensory area, which is an area adjacent to IT (at least for recognition of faces). | 1 | ||
| LaBerge; Attentional Processing | 110 | Three related but slightly different kinds of behavioral tasks involving visual objects: (1) discrimination task, (2) identification task, (3) recognition task. | 0 | ||
| LaBerge; Attentional Processing | 110 | The kinds of objects to which cells in IT preferentially respond vary widely from simple to complex, including objects made up of various combinations of color and texture and shape, faces and hands, toy animals, vegetables, other natural objects. | 0 | ||
| LaBerge; Attentional Processing | 110 | Variations in location and size of objects do not appreciably change the selectivity of IT cells. | 0 | ||
| LaBerge; Attentional Processing | 110 | Cells in IT respond selectively to parts of an object, such as faces. | 0 | ||
| LaBerge; Attentional Processing | 110 | Some IT cells respond to a whole object and others to its parts. | 0 | ||
| LaBerge; Attentional Processing | 122 | Attention to Spatial Information in Dorsal Cortical Streams | 12 | ||
| LaBerge; Attentional Processing | 140 | Attentional Processing in Two Subcortical Areas | 18 | ||
| LaBerge; Attentional Processing | 140 | Superior Colliculus | 0 | ||
| LaBerge; Attentional Processing | 158 | Thalamus | 18 | ||
| LaBerge; Attentional Processing | 160 | The thalamus is divided into three sectors. | 2 | ||
| LaBerge; Attentional Processing | 160 | The dorsal thalamus in which all nuclei send fibers to and receive fibers from the cortex. | 0 | ||
| LaBerge; Attentional Processing | 160 | The epithalamus in which nuclei neither send fibers to nor receive fibers from the cortex. | 0 | ||
| LaBerge; Attentional Processing | 160 | The ventral thalamus in which nuclei receive fibers from but do not send fibers to the cortex. | 0 | ||
| LaBerge; Attentional Processing | 160 | The dorsal thalamus and epithalamus (which contains the reticular nucleus) have been implicated in attentional processing. | 0 | ||
| LaBerge; Attentional Processing | 160 | The lateral geniculate nucleus (LGN) and the medial geniculate nucleus (MGN) contains cells that relay information from the eye and ear, respectively, to the cortex. | 0 | ||
| LaBerge; Attentional Processing | 160 | The ventral posterior lateral nucleus (VPL) relays somatosensory information to the cortex, and the ventroposterior medial nucleus (VPM) contains gustatory relays. | 0 | ||
| LaBerge; Attentional Processing | 160 | The "sensory" thalamic nuclei clearly constitute a minor part of the thalamic volume. | 0 | ||
| LaBerge; Attentional Processing | 160 | The vast majority of the thalamic nuclei project (relay) activity between brain areas, and for this reason they have sometimes been termed "association" nuclei. | 0 | ||
| LaBerge; Attentional Processing | 160 | The largest nucleus in the thalamus is the pulvinar, a Greek term meaning "pillow." | 0 | ||
| LaBerge; Attentional Processing | 161 | Thalamus of One Hemisphere of the Brain (diagram) | 1 | ||
| LaBerge; Attentional Processing | 162 | Main Nuclei of the Human Thalamus (diagram) | 1 | ||
| LaBerge; Attentional Processing | 163 | The pulvinar volume is approximately 2/5 of the thalamic volume, and it has connections with virtually all of the areas of the posterior cortex and many of the areas of anterior cortex. | 1 | ||
| LaBerge; Attentional Processing | 163 | The pulvinar evolved along with the progressive enlargement of the association areas of the posterior cortex. | 0 | ||
| LaBerge; Attentional Processing | 163 | The second-largest thalamic nucleus in humans is the mediodorsal nucleus (MD), which serves the prefrontal areas. | 0 | ||
| LaBerge; Attentional Processing | 163 | Dorsal thalamic nuclei are partially surrounded (particularly on the rostral and lateral aspects) by a thin sheet of neurons called the reticular nucleus. | 0 | ||
| LaBerge; Attentional Processing | 163 | All sensory inputs to the neocortex are relayed through the thalamus, except for the olfactory sensory neurons, which project directly to the paleocortex. | 0 | ||
| LaBerge; Attentional Processing | 163 | The vast majority of signals traversing the thalamus arise from the cortex itself and from a variety of subcortical areas, notably the superior colliculus and the basal ganglia. | 0 | ||
| LaBerge; Attentional Processing | 163 | Virtually every cortical area sends signals to and receives signals from a thalamic nucleus, and there is considerable anatomical precision in the mappings between cortex and thalamus. | 0 | ||
| LaBerge; Attentional Processing | 164 | Thalamocortical Circuit (diagram) | 1 | ||
| LaBerge; Attentional Processing | 166 | Processing in any given cortical area is intimately related to activity in the particular thalamic nucleus with which it has reciprocal and close connections. | 2 | ||
| LaBerge; Attentional Processing | 166 | Pulvinar is responsive to tasks that involve attentional operations. | 0 | ||
| LaBerge; Attentional Processing | 167 | Elevated pulvinar activity during attention tasks has been observed in normal humans by positron emission tomography PET. | 1 | ||
| LaBerge; Attentional Processing | 172 | Thalamic Circuitry | 5 | ||
| LaBerge; Attentional Processing | 173 | Almost all the knowledge we have of the circuitry of the thalamus is based on neurological studies at of the monkey, cat, and rat. The circuitry of the typical thalamic nucleus is apparently quite similar across the species, and comparisons of the histochemical staining in the monkey and human thalamus show identical patterns. | 1 | ||
| LaBerge; Attentional Processing | 173 | Axons of the afferent input to the thalamus terminate on the two types of cells that constitute the dorsal thalamus -- the principal (relay) cells and interneurons. | 0 | ||
| LaBerge; Attentional Processing | 173 | Output of the thalamic circuit is produced by axons of the principal cells that project directly to cells in a column of a particular cortical area. | 0 | ||
| LaBerge; Attentional Processing | 173 | Axons of thalamic principles cells do not contact each other, but as they pierce the reticular nucleus in route to the cortex, they send off collateral axons that terminate on proximal dendrites of reticular nucleus cells. | 0 | ||
| LaBerge; Attentional Processing | 173 | The thalamic column "serves" the cortical area to which the principal cells project. | 0 | ||
| LaBerge; Attentional Processing | 173 | Principle cells of a thalamic column provide channels of information flow through the thalamus to the cortex. | 0 | ||
| LaBerge; Attentional Processing | 174 | For most cortical areas, the main target of thalamocortical projections is layer 3. | 1 | ||
| LaBerge; Attentional Processing | 174 | The typical route of activity flow within a cortical column proceeds from middle layers 3 and 4 to layer 2, then to layer 5, and then to layer 6, where cells project not only back to the thalamus but also back to layer 4. | 0 | ||
| LaBerge; Attentional Processing | 174 | All cortical layers can project via pyramidal axons to sites outside the cortical column -- layers 2 and 3 to other cortical areas, layer 5 to subcortical regions (e.g. SC, basal ganglia), and layer 6 to the thalamus. | 0 | ||
| LaBerge; Attentional Processing | 174 | Thalamic principle cell axons apparently project with some precision to a cortical area. | 0 | ||
| LaBerge; Attentional Processing | 175 | The projections from cortex back to the thalamus occurs mostly by way of layer 6 cells. | 1 | ||
| LaBerge; Attentional Processing | 175 | The afferent inputs to the pulvinar circuit from various cortical areas (such as the PPC) are regarded as the controls on the circuit mechanism that can produce the expression of attention in a localized region of another cortical area (e.g. V4). | 0 | ||
| LaBerge; Attentional Processing | 178 | Layer 5 cells of the cortex tend to be "bursting cells" that are particularly suitable for driving the temporal patterning of thalamocortical cells serving other cortical areas. | 3 | ||
| LaBerge; Attentional Processing | 178 | Bursting cells may amplify and synchronize cortical outputs and may serve to bind feature representations in disparate cortical areas through the synchronous firing patterns. | 0 | ||
| LaBerge; Attentional Processing | 178 | There would seem to be computational advantages in combining temporal binding with spatial sharpening by routing corticocortical projections from the bursting cells through a thalamic circuit. | 0 | ||
| LaBerge; Attentional Processing | 178 | Afferent inputs to the thalamus typically synapse within glomeruli located on proximal dendrites, where the afferents can strongly affect activity at the soma. | 0 | ||
| LaBerge; Attentional Processing | 178 | A glomerulus is a group of synapses surrounded by glia. | 0 | ||
| LaBerge; Attentional Processing | 178 | Interneurons synapse with each other and with principle cell dendrites in inhibitory dendrodendritic profiles. | 0 | ||
| LaBerge; Attentional Processing | 178 | The affects of inhibitory-to-inhibitory synapses are apparently much stronger (approximately 20 times as powerful) as effects in excitatory-to-excitatory synapses. | 0 | ||
| LaBerge; Attentional Processing | 178 | The structure of a glomerulus appears to enable incoming afferent signals to the thalamus to be closely modulated by inhibitory discharges of interneurons, which could shape incoming pulse trains. | 0 | ||
| LaBerge; Attentional Processing | 178 | Interconnections between thalamocortical "columns." | 0 | ||
| LaBerge; Attentional Processing | 178 | Feedback inhibitory action reticular nucleus cells. | 0 | ||
| LaBerge; Attentional Processing | 179 | The axon of a typical reticular nucleus (RN) cell sends a few collaterals to nearby RN cells and then projects into the dorsal thalamus, where it branches extensively. | 1 | ||
| LaBerge; Attentional Processing | 179 | Reticular nucleus axons inhibit principle cells and also inhibit interneurons, which are themselves inhibitory. | 0 | ||
| LaBerge; Attentional Processing | 179 | Reticular nucleus cells inhibit each other and not only by axodendritic synapses but also by the considerable number of dendrodendritic synapses, where the extensive dendritic processes of these cells contact each other. | 0 | ||
| LaBerge; Attentional Processing | 179 | The mutual inhibitory manner of processing in the reticular nucleus makes it difficult to infer at a glance exactly how the reticular nucleus mediates effects between the principle cells. | 0 | ||
| LaBerge; Attentional Processing | 179 | With the help of the neural network model we can more clearly described the computations that the circuit structure might exert upon thalamic-column interactions, and thereby begin to understand how the entire thalamic circuit might function as a mechanism of attention. | 0 | ||
| LaBerge; Attentional Processing | 179 | Much is known about the general effect of reticular nucleus cell discharge on principle cell activity during sleep. | 0 | ||
| LaBerge; Attentional Processing | 179 | A description of thalamic circuit functioning during the general cortical states of drowsiness and deep resting sleep may provide instructive hints about its functioning during states of attention. | 0 | ||
| LaBerge; Attentional Processing | 179 | Thalamocortical activity during a resting sleep. | 0 | ||
| LaBerge; Attentional Processing | 179 | When the brain passes from the alert waking state to deep stages of resting sleep, neural firing does not cease but rather exhibits a profound change in its pattern of discharges. | 0 | ||
| LaBerge; Attentional Processing | 180 | Spindle Rhythm | 1 | ||
| LaBerge; Attentional Processing | 180 | Spindle rhythm is characterized by bursts of spikes that occur in the 7 -- 14 Hz range and last for only 1 -- 3 seconds, with interspike "lulls" of 5 -- 8 seconds. | 0 | ||
| LaBerge; Attentional Processing | 180 | When thalamocortical cells and reticular nucleus cells are hyperpolarized (to -60 millivolts), they respond with rebound bursts of spikes. | 0 | ||
| LaBerge; Attentional Processing | 181 | When information from the external world, encoded in trains of signals arising from the sensory surface, reaches the "sensory" thalamic nuclei (e.g. the LGN for vision, the MGN for audition, and the ventroposterior lateral nucleus, VPLN, for touch), rhythmic bursts of high frequency spikes in the thalamocortical (relay) neurons apparently destroy that information, and hence the cortex is deprived of sensory stimulation. | 1 | ||
| LaBerge; Attentional Processing | 181 | When information arising from one cortical area is projected to another cortical area through the "association" nuclei of the thalamus (such as the pulvinar or mediodorsal nuclei), it is blocked by the burst firing in the thalamocortical neurons and thus prevented from combining its effects with the information flowing across the direct corticocortical connections. | 0 | ||
| LaBerge; Attentional Processing | 181 | Delta Rhythm | 0 | ||
| LaBerge; Attentional Processing | 183 | Thalamocortical activity compared during sleep and waking. | 2 | ||
| LaBerge; Attentional Processing | 198 | The thalamus as a mechanism of selective attention. | 15 | ||
| LaBerge; Attentional Processing | |||||