Vocalization-correlated single-unit activity in the brain stem of the squirrel monkey

Summary The brain stems of 17 squirrel monkeys (Saimiri sciureus) were systematically explored for vocalization-related single-unit activity during calls electrically elicited from the periaqueductal grey. Of 12,280 cells tested, 1151 fired in relation to vocalization. Of these, 587 reacted to external acoustic stimuli and started firing after vocalization onset. As most of these cells were located in classical auditory relay structures, they probably represent auditory neurones reacting indirectly to self-produced vocalization due to auditory feedback. Seven cells reacted to acoustic stimuli but fired in advance of self-produced vocalization. These cells were locoated in the pericentral inferior colliculus, dorsal nucleus of the lateral lemniscus, dorsomedial to the ventral nucleus of the lateral lemniscus and immediately lateral to the central grey. They are probably engaged in tuning the auditory system to process self-generated sounds differently from external sounds. 261 neurones reacted to nonphonatory oral movements (chewing, swallowing) and started firing after vocalization onset. These neurones were widely distributed within the brain stem, with the highest density in the spinal trigeminal nucleus and medially adjacent reticular formation. The majority of these cells seem to react to proprioceptive and tactile stimuli generated by phonatory and nonphonatory oral activities. Some of them may exert motor control on muscles that come into play at later stages of phonation. 57 neurones reacted to nonphonatory oral movements but fired in advance of vocalization onset. These neurones were located mainly in the trigeminal motor nucleus, nucl. ambiguus, reticular formation around these nuclei, parabrachial region and lateral vestibular nucleus. Their role in motor control seems to be related to specific muscles rather than specific functions. 100 of the vocalization-related cells showed a correlation with respiration. Expiration-related cells were found in and around the rostral nucl. ambiguus and in the reticular formation dorsal to the facial nucleus. Inspiration-related cells were located in the rostral and caudal nucl. ambiguus regions, ventrolateral solitary tract nucleus and the lateral reticular formation below the trigeminal motor nucleus. Most of these cells probably represent premotor neurones of respiratory muscles and laryngeal motoneurones of the cricothyroid and posterior cricoarytenoid muscles. Finally, a last group of cells was found that was unresponsive to chewing and swallowing movements, quiet breathing and acoustic stimuli, but changed activity during vocalization. 38 of them became active before vocalization and cricothyroid activity, and 101 afterward. Both types were completely intermingled and scattered widely in the brain stem, including the nucl. ambiguus region, solitary tract nucleus, nucl. reticularis parvocellularis and gigantocellularis, parabrachial region, pericentral colliculus inferior, vestibular complex, periventricular grey and laterally adjacent tegmentum. Some of these cells may be related to vocalization in a more specific way.Abbreviations A nucl. annularis - Ab nucl. ambiguus - Apt area praetectalis - BC brachium conjunctivum - BP brachium pontis - Cb cerebellum - CC corpus callosum - Cd nucl. caudatus - Col colliculus inferior - CoS colliculus superior - CRf corpus restiforme - DBC decussatio brachii conjunctivi - DG nucl. dorsalis tegmenti (Gudden) - DR nucl. dorsalis raphae - DV nucl. ventralis n. vagi - FRM formatio reticularis myelencephali - FRP formatio reticularis pontis - FRTM formatio reticularis mesencephali - GC substantia grisea centralis - GL corpus geniculatum laterale - GM corpus geniculatum mediale - GPM griseum periventriculare mesencephali - GPo griseum pontis - H habenula - Hip hippocampus - IP nucl. interpeduncularis - LC locus coeruleus - LL lemniscus lateralis - LLd nucl. dorsalis lemnisci lateralis - LLv nucl. ventralis lemnisci lateralis - LM lemniscus medialis - LP nucl. lateralis posterior thalami - MD nucl. medialis dorsalis thalami - MV nucl. motorius n. trigemini - NC nucl. cochlearis - NCb nucl. cerebelli - NCS nucl. centralis superior - NCT nucl. trapezoidalis - NR nucl. ruber - NST nucl. supratrochlearis - NSV nucl. spinalis n. trigemini - NTS nucl. tractus solitarii - NIII nucl. oculomotorius - NIV nucl. trochlearis - nV nervus trigeminus - NVI nucl. abducens - NVII nucl. facialis - NXII nucl. hypoglossus - OI oliva inferior - PbL nucl. parabrachialis lateralis - PbM nucl. parabrachialis medialis - Pp nucl. praepositus - Pu nucl. pulvinaris oralis - PuL nucl. pulvinaris lateralis - PuM nucl. pulvinaris medialis - Py tractus pyramidalis - PV nucl. principalis n. trigemini - RL nucl. reticularis lateralis - RTP nucl. reticularis tegmenti pontis - SN substantia nigra - ST stria terminalis - Ves nucl. vestibulares - VR nucl. ventralis raphae - IV decussatio n. trochlearis Supported by Deutsche Forschungsgemeinchaft grant Ju 181/1     

Histochemical mapping of succinic dehydrogenase and cytochrome oxidase in the pons and mesencephalon of squirrel monkey (Saimiri sciureus)

Summary The distribution of succinic dehydrogenase (SDA) and cytochrome oxidase (Cy. O) has been investigated in a series of sections through the pons and mesencephalon of the squirrel monkey brain. The localization of the two enzymes is very similar in the various regions and shows only slight differences. The epiphysis, however, shows moderately strong SDA and very mild Cy. O activity. Particularly strong SDA and Cy. O activity has been observed in the cell bodies of the various cranial nerve nuclei, nucleus colliculi inferioris, colliculi superioris, nuclei griseum pontis, reticularis tegmenti pontis, lemnisci lateralis pars dorsalis, geniculatum laterale and mediale, and pulvinaris. The enzyme content of the neurons and cell bodies is generally stronger compared to the neuropil which often occurs in smooth, loose, compact and reticulated forms. Any special relationship between the neurons and neuropil with regard to their enzyme content has, however, not been observed. The cranial nerves, and fibers of the brachium conjunctivum, corpus callosum, and fornix show very mild enzyme activity except those of the trapezoid complex which show moderate enzyme activity.Abbreviations Ann Nucleus annularis - APT Area praetectalis - AS Aquaeductus Sylvii - BC Brachium conjunctivum - BCI Brachium colliculi inferioris - BCS Brachium colliouli superioris - BP Brachium pontis - Cb Cerebellum - CC Corpus callosum - CCI Commissura colliculi inferioris - CCS Commissura colliculi superioris - Cd Nucleus caudatus - CHD Commissura hippocampi —parsdorsalis - CoI Colliculus inferior - CoP Commissura posterior - CoR Corona radiata - CoS Colliculus superior - CPf Cortex piriformis - CR Cortex retrosplenialis - DBC Decussatio brachii conjunctivi - DG Nucleus dorsalis tegmentalis(Gudden) - DR Nucleus dorsalis raphes - EP Epiphysis - F Fornix - FH Fimbria hippocampi - FLM Fasciculus longitudinalis medialis - FRPC Formatio reticularis pontis, parscaudalis - FRPO Formatio reticularis pontis, parsoralis - FRTM Formatio reticularis tegmentimesencephali - GC Substantia grisea centralis - GCd Substantia grisea centralis, parsdorsalis - GCv Substantia grisea centralis, parsventralis - GL Corpus geniculatum laterale - GM Corpus geniculatum mediate - GPO Griseum pontis - Hipp Hippocampus - HL Nucleus habenulae lateralis - HM Nucleus habenulae medialis - IP Nucleus interpeduncularis - LC Nucleus locus coeruleus - LCb Lingula cerebelli - Lim Nucleus limitans thalami - LL Lemniscus lateralis - LLD Nucleus lemnisci lateralis —parsdorsalis - LM Lemniscus medialis - LP Nucleus lateralis posterior thalami - MD Nucleus medialis dorsalis thalami - Mv Nucleus motorius n. trigemini - NCI Nucleus colliculi inferioris - NCS Nucleus centralis superior tegmenti - NCT Nucleus trapezoideum - NMv Nucleus tractus mesencephalicus n.trigemini - NR Nucleus ruber - NST Nucleus supratrochlearis - NSv Nucleus tractus spinalis n. trigemini - NiiiC Nucleus centralis n. oculomotorii - NiiiD Nucleus n. oculomotorii — pars dor-salis - NiiiV Nucleus n. oculomotorii — pars ven-tralis - Niv Nucleus n. troehlearis - nvm Nervus trigeminus, portio major - niv Nervus trochlearis - nvi Nervus abducens - OS Nucleus olivaris superior - P Nucleus posterior thalami - PbL Nucleus parabrachialis lateralis - PbM Nucleus parabrachialis medialis - PC Pedunculus cerebri - Pg Nucleus parabigeminalis - PUI Nucleus pulvinaris inferior thalami - PUL Nucleus pulvinaris lateralis thalami - PUM Nucleus pulvinaris medialis thalami - Py Tractus pyramidalis - Pv Nucleus principalis n. trigemini - R Nucleus reticularis thalami - RTP Nucleus reticularis tegmenti pontis - SNc Substantia nigra — pars compacta - SNd Substantia nigra — pars diffusa - Sub Subiculum - TCT Tractus corticotectalis - VR Nucleus ventralis raphes - III Ventriculus tertius - IV Ventriculus quartus     

The cingular vocalization pathway in the squirrel monkey

Summary In 39 squirrel monkeys (Saimiri sciureus), the effects of various brain lesions on vocalizations elicited from the precallosal cingulate gyrus were tested. It was found that lesions abolishing the cingular vocalization completely can be traced from the stimulation site continuously down to the laryngeal motoneurons in the nucleus ambiguus. The pathway thus determined (Fig. 4) travels from the precallosal cingulate gyrus through the frontal white matter and enters the internal capsule from a dorsolateral position. The pathway then follows this structure in a medio-caudal direction down to the caudal diencephalon. Here, the effective lesions leave the corticospinal tract and ascend dorsally into the periaqueductal grey. The pathway follows this structure to its end where it sweeps lateral through the parabrachial area and then descends through the lateral pons and ventrolateral medulla to the nucleus ambiguus.In nine of the animals, in addition, the effects of bilateral anterior cingular lesions on vocalizations elicited in other brain areas were tested. It was found that the only vocalization-eliciting area which becomes ineffective after destruction of the anterior cingulate gyrus is the postero-medial orbital cortex.Abbreviations a nucl. accumbens - aa area anterior amygdalae - ab nucl. basalis amygdalae - ac nucl. centralis amygdalae - al nucl. lateralis amygdalae - am nucl. medialis amygdalae - an nucl. anterior thalami - aq griseum centralis - bc brachium conjunctivum - ca caudatum - cb cerebellum - cc corpus callosum - cen nucl. centralis superior Bechterew - ci capsula interna - cin cingulum - cl claustrum - coa commissura anterior - coli colliculus inferior - cols colliculus superior - cop commissura posterior - cr corpus restiforme - csp tractus corticospinalis - db fasciculus diagonalis Brocae - dbc decussatio brachii conjunctivi - f fornix - gc gyrus cinguli - gl geniculatum laterale - gm geniculatum mediale - gp globus pallidus - gr gyrus rectus - gs gyrus subcallosus - h area tegmentalis (Forel) - ha habenula - hi tractus habenulo-interpeduncularis - hip hippocampus - hya hypothalamus anterior - hyv hypothalamus ventromedialis - in nucl. interpeduncularis - lap nucl. lateralis posterior thalami - lem lemniscus medialis - lm fasciculus longitudinalis medialis - m nucl. mammillaris - md nucl. medialis dorsalis thalami - mt tractus mammillothalamicus - nst nucl. striae terminalis - nts nucl. solitarius - oi oliva inferior - ol fasciculus olfactorius (Zuckerkandl) - os oliva superior - p pedunculus cerebri - pmc brachium pontis - po griseum pontis - pro area praeoptica - pu nucl. pulvinaris - put putamen - re formatio reticularis mesencephali - rep nucl. reticularis tegmenti pontis - rl nucl. reticularis lateralis - rub nucl. ruber - s septum - sm stria medullaris - sn substantia nigra - st stria terminalis - sto stria olfactoria lateralis - tec tractus tegmentalis centralis - trz corpus trapezoideum - va nucl. ventralis anterior thalami - ves nucl. vestibularis - vpl nucl. ventralis posterior lateralis th. - vpm nucl. ventralis posterior medialis th. - zi zona incerta - II tractus opticus - IIchde chiasma n. opticorum - III nucl. n. oculomotorii and n. oculomotorius - IV nucl. n. trochlearis - VI n. abducens - VII nucl. n. facialis and n. facialis - VIII n. acusticus - XII nucl. n. hypoglossi     

Reinforcing concomitants of electrically elicited vocalizations

Summary In 38 squirrel monkeys 251 vocalization-producing electrode positions were tested for their positive and negative reinforcing properties. Two groups of vocalization-producing brain areas could be distinguished: One group in which the electrically elicited vocalization was independent of the accompanying reinforcement effect, and a second group in which vocalization and reinforcement effect were correlated. The first group included the anterior cingulate gyrus, the adjacent supplementary motor area, gyrus rectus, ventromedial edge of the capsula interna, caudal periaqueductal gray and adjacent parabrachial region. The second group consisted of the caudatum, septum, substantia innominata, amygdala, inferior thalamic peduncle, stria terminalis, midline thalamus, ventral and periventricular hypothalamus, substantia nigra, rostral periaqueductal gray, dorsolateral midbrain tegmentum and lateral medulla. It is hypothesized that the first group contains predominantly or exclusively primary vocalization subtrates; the second group is thought to be composed mainly of structures whose stimulation yields vocalization secondarily due to stimulus induced motivational changes.Abbreviations a nucl. accumbens - aa area anterior amygdalae - ab nucl. basalis amygdalae - ac nucl. centralis amygdalae - al nucl. lateralis amygdalae - an nucl. anterior thalami - anl ansa lenticularis - aq substantia grisea centralis - bc brachium conjunctivum - ca nucl. caudatus - cc corpus callosum - cen nucl. centralis superior tegmenti - cent centrum medianum - ci capsula interna - cin cingulum - cl claustrum - coa commissura anterior - coli colliculus inferior - cols colliculus superior - csp tractus cortico-spinalis - db fasciculus diagonalis Brocae - dbc decussatio brachii conjunctivii - f fornix - gc gyrus cinguli - gl corpus geniculatum laterale - gm corpus geniculatum mediale - gp globus pallidus - gr gyrus rectus - gs gyrus subcallosus - h campus Foreli - ha nucl. habenularis - hi tractus habenulo-interpeduncularis - hip hippocampus - hya area hypothalamica anterior - hyl area hypothalamica lateralis - hyv nucl. ventromedialis hypothalami - in nucl. interpeduncularis - lap nucl. lateralis posterior thalami - lav nucl. ventralis lateralis thalami - le lemniscus lateralis - lem lemniscus medialis - lm fasciculus longitudinalis medialis - m corpus mamillare - md nucl. medialis dorsalis thalami - mt tractus mamillo-thalamicus - nst nucl. striae terminalis - oi nucl. olivaris inferior - ol fasciculus olfactorius Zuckerkandl - os nucl. olivaris superior - p pedunculus cerebri - pmc brachium pontis - po griseum pontis - pro area praeoptica - pu nucl. pulvinaris thalami - put putamen - re formatio reticularis - rep nucl. reticularis tegmenti pontis - rub nucl. ruber - s septum - sm stria medullaris - sn substantia nigra - st stria terminalis - sto tria olfactoria lateralis - subt subthalamus - tec tractus tegmentalis centralis - trz corpus trapezoideum - va nucl. ventralis anterior thalami - vpl nucl. ventralis postero-lateralis - vpm nucl. ventralis postero-medialis - zi zona incerta - II tractus opticus - IIch chiasma nervorum opticorum - III n. oculomotorius and nucl. n. oculomotorii - IV n. and nucl. n. trochlearis - VI n. abducens and nucl. n. abducentis - VII nucl. n. facialis - VIII nucl. cochlearis - IX n. hypoglossus     

Distribution of methionine-enkephalin in the minipig brainstem

We have studied the distribution of immunoreactive cell bodies and axons are containing methionine-enkephalin in the minipig brainstem. Immunoreactive axons were widely distributed, whereas the distribution of perikarya was less widespread. A high or moderate density of axons containing methionine-enkephalin were found from rostral to caudal levels in the substantia nigra, nucleus interpeduncularis, nucleus reticularis tegmenti pontis, nucleus dorsalis raphae, nucleus centralis raphae, nuclei dorsalis and ventralis tegmenti of Gudden, locus ceruleus, nucleus sensorius principalis nervi trigemini, nucleus cuneatus externalis, nucleus tractus solitarius, nuclei vestibularis inferior and medialis, nucleus ambiguus, nucleus olivaris inferior and in the nucleus tractus spinalis nervi trigemini. Immunoreactive perikarya were observed in the nuclei centralis and dorsalis raphae, nucleus motorius nervi trigemini, nucleus centralis superior, nucleus nervi facialis, nuclei parabrachialis medialis and lateralis, nucleus ventralis raphae, nucleus reticularis lateralis and in the formatio reticularis. We have also described the presence of perikarya containing methionine-enkephalin in the nuclei nervi abducens, ruber, nervi oculomotorius and nervi trochlearis. These results suggest that in the minipig the pentapeptide may be involved in many physiological functions (for example, proprioceptive and nociceptive information; motor, respiratory and cardiovascular mechanisms).     

Projections from the primary somatosensory cortex to basal ganglia and thalamus in the monkey

Summary Radioactive amino acids were injected into the postcentral cortex (areas 3, 1 and 2) in 6 monkeys (Macaca fascicularis). Fibers were traced to the ipsilateral putamen, to Olszewski's n. ventralis posterior lateralis pars caudalis, n. ventralis posterior medialis and inferior, to n. pulvinaris oralis, n. suprageniculatus and corpus geniculatum mediale pars magnocellularis. Furthermore, there were faint postcentral projections to claustrum, n. caudatus, n. centralis lateralis, n. centrum medianum, zona incerta and with respect to the postcentral face region to n.medialis dorsalis pars multiformis.Discrepancies with earlier findings were discussed and comparison was made between pre- and postcentral target regions.Abbreviations Cd n. caudatus - ci capsula interna - CL n. centralis lateralis - Cl claustrum - CM n. centrum medianum - GL corpus geniculatum laterale - GM corpus geniculatum mediale - GMpc corpus geniculatum mediale pars parvocellularis - GMmc corpus geniculatum mediale pars magnocellularis - GP globus pallidus - la sulcus lateralis - LP n. lateralis posterior - MD n. medialis dorsalis - OI opercular-insular cortex - Pen n. paracentralis - Pf n. parafascicularis - PI n. pulvinaris inferior - PO n. pulvinaris oralis - Pu putamen - RT n. reticularis thalami - SG n. suprageniculatus - SN substantia nigra - St n. subthalamicus - thi tractus habenulo-interpeduncularis - tmt tractus mammillo-thalamicus - to tractus opticus - VA n. ventralis anterior - VLc n. ventralis lateralis, p. caudalis - VLo n. ventralis lateralis, p. oralis - VPI n. ventralis posterior inferior - VPL n. ventralis posterior lateralis - VPLc n. ventralis posterior lateralis p. caudalis - VPLo n. ventralis posterior lateralis p. oralis - VPM n. ventralis posterior medialis - ZI zona incerta     

Convergent projections of different limbic vocalization areas in the squirrel monkey

Summary The projections of four different sub-areas within the anterior limbic cortex, all yielding vocalization when electrically stimulated, were compared in six squirrel monkeys by the autoradiographic tracing technique.Areas of convergence of the projections from all four vocalization loci were the cortex within the anterior cingulate sulcus, a zone following the inferior thalamic peduncle from the central amygdaloid nucleus through the substantia innominata into the midline thalamus, a second zone following the periventricular fibre system from the anterior diencephalon to the caudal midbrain and dorsolateral pontine tegmentum and, finally, the tail of the caudate nucleus. Except for the latter, all of these brain structures produce vocalization when electrically stimulated. The call types elicitable from these projection areas are sometimes different from those elicitable from the anterior limbic cortex. It is hypothesized that the anterior limbic cortex controls vocalization directly, independently of the specific motivational state underlying it.Abbreviations to Figures 2 and 3 a nucl. accumbens - aa area anterior amygdalae - ab nucl. basalis accessorius amygdalae - ac nucl. centralis amygdalae - an nucl. anterior thalami - anl ansa lenticularis - aq substantia grisea centralis - ba nucl. basalis amygdalae - bc brachium conjunctivum - ca nucl. caudatus - cc corpus callosum - cent centrum medianum - ci capsula interna - cl claustrum - coa commissura anterior - coi colliculus inferior - csp tractus cortico-spinalis - gc gyrus cinguli - gl corpus geniculatum laterale - gm corpus geniculatum mediale - gp globus pallidus - gpm griseum periventriculare mesencephali - gr gyrus rectus - gts gyrus temporalis superior - h campus Foreli - ha nucl. habenularis - hip hippocampus - hy hypothalamus - lap nucl. lateralis posterior thalami - lem lemniscus medialis - m corpus mamillare - md nucl. medialis dorsalis thalami - os nucl. olivaris superior - p pedunculus cerebri - po griseum pontis - pro area praeoptica - pu nucl. pulvinaris thalami - put putamen - re formatio reticularis - s septum - sm stria medullaris - sn substantia nigra - st stria terminalis - tp cortex temporalis anterior - va nucl. ventralis anterior thalami - vpl nucl. ventralis postero-lateralis th. - vpm nucl. ventralis postero-medialis th. - III N. oculomotorius The study was carried out in accordance with the Guiding Principles in the Care and Use of Primates approved by the Council of the American Physiological Society.     

The laryngeal sensory pathway and its role in phonation. A brain lesioning study in the squirrel monkey

Summary In 10 squirrel monkeys (Saimiri sciureus) uni- or bilateral lesions were placed in the nucl. solitarius, parabrachial nuclei, nucl. ventralis posterior medialis thalami or face area of primary sensory cortex. The effects of these lesions on vocalization were compared with those after transection of the internal branch of the superior laryngeal nerve. It was found that neither the cortical nor thalamic or parabrachial lesions changed the acoustic structure of vocalization. In contrast, destruction of the nucl. solitarius, like transection of the internal branch of the superior laryngeal nerve, affected vocalization severely. It is concluded that the production of species-specific vocalization depends upon a di- or, possibly, tri-synaptic laryngeal reflex control from tactile and proprioceptive laryngeal mechanoreceptors via nucl. solitarius and, possibly, lateral medullary reticular formation to nucl. ambiguus.Abbreviations a amygdala - aq griseum periaquaeductale - bc brachium conjunctivum - ca nucl. caudatus - cb cerebellum - cent centrum medianum - ci capsula interna - cl claustrum - coa commissura anterior - coli colliculus inferior - cols colliculus superior - cr corpus restiforme - csp tractas corticospinalis - f fornix - gp globus pallidus - h campus Foreli - hip hippocampus - hy hypothalamus - lap nucl. lateralis posterior th - lem lemniscus medialis - lm fasciculus longitudinalis medialis - md nucl. medialis dorsalis th - nts nucl. tr. solitarius - oi oliva inferior - os oliva superior - p pedunculus cerebri - pmc brachium pontis - put putamen - rl nucl. reticularis lateralis - rub nucl. ruber - sm stria medullaris - sn substantia nigra - st stria terminalis - va nucl. ventralis anterior th - ves nucl. vestibularis - vpm nucl. ventralis posterior medialis th - II tractas opticus - IIch chiasma opticum - III n. oculomotorius - IV n. trochlearis - VI n. abducens - VII n. facialis - VIII nucl. cochlearis - XII nucl. n. hypoglossi     

Projections from the cortical larynx area in the squirrel monkey

Summary The projections from the cortical vocal fold area were studied in five squirrel monkeys (Saimiri sciureus) with the aid of the autoradiographie tracing technique. The location of the cortical vocal fold area was determined by exploring the exposed frontal cortex with roving electrodes while examining the larynx for vocal fold adduction. The following projections were found: To the orbital cortex (area 11), dorsomedial frontal cortex (areas 6 and 8), Broca's area (area 44), lower fronto-parietal cortex (areas 6, 4, 3 and 1), fronto-parietal operculum (area 50), insula (areas 14 and 13), caudatum, putamen, claustrum nucl. reticularis th., nucl. ventralis anterior, nucl. ventralis lateralis, nucl. ventralis posteromedialis, nucl. centralis inferior, nucl. centralis lateralis, nucl. medialis dorsalis, nucl. pulvinaris medialis, griseum pontis, nucl. parabrachialis medialis and lateralis, nucl. tr. spinalis n. trigemini and nucl. tr. solitarii.A comparison of this projection system with a previous mapping study for vocalization (Jürgens and Ploog, 1970) revealed that there are two areas yielding vocalization when electrically stimulated which receive direct projections from the cortical larynx area, namely, the cortex around the anterior sulcus cinguli and the parabrachial nuclei at the pons-midbrain transition. The possible relevance of these structures for vocalization is discussed.     

The vestibulothalamic projections in the cat studied by retrograde axonal transport of horseradish peroxidase

Summary Horseradish peroxidase (HRP) was injected or iontophoretically ejected in various thalamic nuclei in 63 adult cats. In 11 other animals HRP was deposited outside the thalamic territory. The number and distribution of labelled cells within the vestibular nuclear complex (VC) were mapped in each case. To a varying degree all subgroups of VC appear to contribute to the vestibulothalamic projections. Such fibres are distributed to several thalamic areas. From the present investigation it appears that generally speaking, there exist three distinct vestibulothalamic pathways with regard to origin as well as to site of termination of the fibres. One projection appears to originate mainly in caudal parts of the medial (M) and descending (D) vestibular nuclei and in cell group z. This pathway terminates chiefly in the contralateral medial part of the posterior nucleus of the thalamus (POm) including the magnocellular part of the medial geniculate body (Mgmc), the ventrobasal complex (VB) and the area of the ventral lateral nucleus (VL) bordering on VB. A second projection originates mainly in the superior vestibular nucleus (S) and in cell group y and terminates mainly in the contralateral nucleus centralis lateralis (CL) and the adjoining nucleus paracentralis (Pc). A third, more modest, pathway originates chiefly in the middle M and D, with a minor contribution from S and cell group y, and terminates in the contralateral ventral nucleus of the lateral geniculate body (GLV). There is some degree of overlap between the origin of these three vestibulothalamic pathways.Abbreviations B.c. brachium conjunctivum - CeM nucleus centralis medialis thalami - CL nucleus centralis lateralis thalami - CM nucleus centrum medianum - D nucleus vestibularis descendons - f cell group f - g cell group g - GLD corpus geniculatum laterale dorsalis - GLV corpus geniculatum laterale ventralis - i.e. nucleus intercalatus - L nucleus vestibularis lateralis - LD nucleus lateralis dorsalis thalami - LIM lamina medullaris interna - Lim nucleus limitans - LP nucleus lateralis posterior thalami - M nucleus vestibularis medialis - MD nucleus medialis dorsalis thalami - MGmc corpus geniculatum mediale, pars magnocellularis - MGp corpus geniculatum mediale, pars principalis - N.cu.e. nucleus cuneatus externus - N.f.c. nucleus fasciculi cuneati - N.mes. V nucleus mesencephalicus nervi trigemini - NR nucleus ruber - N.tr.s. nucleus tractus solitarius - N. VII nervus facialis - N. VIII nervus statoacusticus - PC pedunculus cerebri - Pc nucleus paracentralis thalami - Pf nucleus parafascicularis - p.h. nucleus prepositus hypoglossi - PO posterior thalamic group - PO1 lateral part of PO - POm medial part of PO - Prt nucleus pretectalis - Pul pulvinar - R nucleus reticularis thalami - S nucleus vestibularis superior - Sg nucleus suprageniculatus - SN substantia nigra - Sv nucleus supravestibularis - Tr.s. tractus solitarius - VA nucleus ventralis anterior thalami - VL nucleus ventralis lateralis thalami - VPL nucleus ventralis posterior lateralis - VPL1 lateral part of VPL - VPLm medial part of VPL - VPM nucleus ventralis posterior medialis - x cell group x - y cell group y - z cell group z - V nucleus motorius nerve trigemini - X nucleus dorsalis nerve vagi - XII nucleus nervi hypoglossi     

Afferent fiber connections from lower brain stem to hypothalamus studied by the horseradish peroxidase method with special reference to noradrenaline innervation

Summary Attempts were made to determine the afferent projections to the anterior hypothalamus including the preoptic area from the lower brain stem by means of the horseradish peroxidase method combined with monoamine oxidase staining to identify noradrenaline (NA) neurons. In addition to this technique, a histofluorescence analysis was performed. NA fibers in the medial part of the anterior hypothalamus were mainly supplied by A1 and A2 NA neuron groups, while the lateral part and periventricular zone received NA terminals from both pontine and medulla oblongata NA neuron groups. Furthermore, the present study indicated that there were direct projections to the anterior hypothalamus from non-noradrenergic neurons in the lower brain stem: nuclei raphe dorsalis, centralis superior, cells in the mesencephalic and pontine central gray matter, nuclei parabrachialis lateralis and medialis, cells around fasciculus longitudinalis medialis.Abbreviations CA Commissura anterior - CO Chiasma opticum - DP Decussatio pyramidum - DPCS Decussatio pedunculorum cerebellarium superiorum - F Columna fornicis - FLM Fasciculus longitudinalis medialis - FMT Fasciculus mamillothalamicus - GCM Griseum centrale mesencephali - GCP Griseum centrale pontis - LL Lemniscus lateralis - LM Lemniscus medialis - PCM Pedunculus cerebellaris medius - PCS Pedunculus cerebellaris superior - TO Tractus opticus - TS Tractus solitarius - TVme Tractus mesencephalicus nervi trigemini - V Ventriculus tertius - VTS Tractus spinalis nervi trigemini - am nucleus ambiguus - B Barrington nucleus - com nucleus commissuralis - cp nucleus caudatus putamen - cs nucleus centralis superior - ct nucleus corporis trapezoidei - cu nucleus cuneatus - dX nucleus dorsalis nervi vagi - Gd nucleus tegmentalis dorsalis (von Gudden) - gr nucleus gracilis - Gv nucleus tegmentalis ventralis (von Gudden) - ha nucleus hypothalamicus anterior - hl nucleus hypothalamicus lateralis - hpe nucleus periventricularis (hypothalami) - hvm nucleus ventromedialis hypothalami - lc nucleus locus coeruleus - oi nucleus olivaris inferior - p nucleus pontis - pa nucleus paraventricularis - pbl nucleus parabrachialis lateralis - pbm nucleus parabrachialis medialis - ph nucleus praepositus hypoglossi - pol nucleus preopticus lateralis - pom nucleus preopticus medialis - pop nucleus preopticus periventricularis - rd nucleus raphe dorsalis - re nucleus reuniens - rl nucleus reticularis lateralis - rm nucleus raphe magnus - ro nucleus raphe obscrus - sc nucleus suprachiasmaticus - so nucleus supraopticus - st nucleus interstitialis striae terminalis - td nucleus tractus diagonalis (Broca) - ts nucleus tractus solitarii - Vme nucleus mesencephalicus nervi trigemini - Vmo nucleus motorius nervi trigemini - Vts nucleus tractus spinalis nervi trigemini - XII nucleus nervi hypoglossi     

Cerebral representation of vocalization in the squirrel monkey

Summary Specific vocalization types following electrical stimulation of 5940 electrode positions are studied in 39 squirrel monkeys. Except cerebellum, caudal medulla, and a few cortical areas, the sites of stimulation were distributed throughout the brain. Each vocalization elicited was tested for reproducibility at the site of stimulation and in homologue structures. All vocalizations were analyzed spectrographically and then classified for eight fundamental vocalization types.The cerebral distribution of two call types forms continuous systems extending from midbrain via diencephalon into forebrain; the remaining call types are represented in several separate areas not continuous with each other. In medulla and pons the responsive substrates for vocalization follow the course of the spinothalamic tract; in midbrain they lie within the periaqueductal gray, lateral tegmentum, and lemniscus medialis; in diencephalon they are found in the hypothalamus and midline thalamus; in forebrain, finally they are distributed over amygdala, stria terminalis, substantia innominata, preoptic region, septum, rostral hippocampus, posteromedial orbital cortex, cingulate gyrus, and rostroventral temporal cortex. Hence a close relation between limbic system and vocalization producing substrates emerges.Among the brain structures yielding vocalization the mesencephalic periaqueductal gray is assumed to be the region where the electrical stimulus interferes most directly with specific vocalization mechanisms.Besides the anatomical site of stimulation the set of stimulus parameters is important for the elicitation of vocalizations. Relations between amplitude, frequency, and duration of impulses on the one hand and type, loudness, rhythm, duration, and latency of vocalization on the other hand were tested. The influence of the stimulus set on the reaction parameters depends also on the relative position of the electrode within the effective structure. Proper manipulation of stimulus parameters often results in the disintegration of a complex stimulus response into single components.Abbreviations a Nucl. accumbens - aa Area anterior amygdalae - ab Nucl. basalis amygdalae - ac Nucl. centralis amygdalae - al Nucl. lateralis amygdalae - am Nucl. medialis amygdalae - an Nucl. anterior thalami - anl Ansa lenticularis - aq Substantia grisea centralis - bc Brachium conjunctivum - ca Caudatum - cc Corpus callosum - cen Nucl. centralis superior (Bechterew) - cent Centrum medianum - ci Capsula interna - cin Cingulum - cl Claustrum - coa Commissura anterior - coli Colliculus inferior - cols Colliculus superior - cr Corpus restiforme - csp Tr. corticospinalis - db Fasc. diagonalis Brocae - dbc Decussatio brachii conjunctivi - f Fornix - gc Gyrus cinguli - gl Corpus geniculatum laterale - gm Corpus geniculatum mediale - gr Gyrus rectus - gs Gyrus subcallosus - h Campus Foreli - ha Nucl. habenularis - hi Tr. habenulointerpeduncularis - hip Hippocampus - hya Area hypothalamica anterior - hyp Area hypothalamica posterior - hyv Area hypothalamica ventralis - in Nucl. interpeduncularis - lap Nucl. lateralis posterior thalami - lav Nucl. lateralis ventralis thalami - le Lemniscus lateralis - lem Lemniscus medialis - lm Fasc. longitudinalis medialis - m Corpus mamillare - md Nucl. medialis dorsalis thalami - mt Tr mamillothalamicus - nst Nucl. striae terminalis - oi Nucl. olivaris inferior - ol Fasc. olfactorius (Zuckerkandl) - os Nucl. olivaris superior - p Pedunculus cerebri - pmc Brachium pontis - po Griseum pontis - pp Nucl. praepositus hypoglossi - pro Area praeoptica - pu Nucl. pulvinaris thalami - put Putamen - re Formatio reticularis tegmenti - rep Nucl. reticularis tegmenti pontis - rl Nucl. reticularis lateralis myelencephali - rub Nucl. ruber - s Septum - sm Stria medullaris - sn Substantia nigra - st Stria terminalis - sto Stria olfactoria lateralis - tec Tr. tegmentalis centralis - trz Corpus trapezoides - va Nucl. ventralis anterior - vpl Nucl. ventralis posterolaterali thalami - vpm Nucl. ventralis posteromedialis thalami - zi Zona incerta - II Tr. options - IICh Chiasma nervorum opticorum - III N. oculomotorius Nucl. nervi oculomotorii - IV N. and Nucl. nervi trochlearis - VI N. abducens - VII N. facialis - VIII N. acusticus - IX N. glossopharyngeus     

Distribution of serotonin-immunoreactivity in the brain of the pigeon (Columba livia)

The distribution of serotonin (5-HT)-containing perikarya, fibers and terminals in the brain of the pigeon (Columba livia) was investigated, using immunohistochemical and immunofluorescence methods combined with retrograde axonal transport. Twenty-one different groups of 5-HT immunoreactive (IR) cells were identified, 2 of which were localized at the hypothalamic level (periventricular organ, infundibular recess) and 19 at the tegmental-mesencephalic and rhombencephalic levels. Ten of the cell groups were situated within the region of the midline from the isthmic to the posterior rhombencephalic level and constituted the raphe system (nucleus annularis, decussatio brachium conjunctivum, area ventralis, external border of the nucleus interpeduncularis, zona peri-nervus oculomotorius, zona perifasciculus longitudinalis medialis, zona inter-flm, nucleus linearis caudalis, nucleus raphe superior pars ventralis, nucleus raphe inferior). The 9 other cell populations belonged to the lateral group and extended from the posterior mesencephalic tegmentum to the caudal rhombencephalon [formatio reticularis mesencephali, nucleus ventrolateralis tegmenti, ectopic area (Ec) of the nucleus isthmo-opticus (NIO), nucleus subceruleus, nucleus ceruleus, nucleus reticularis pontis caudalis, nucleus vestibularis medialis, nucleus reticularis parvocellularis and nucleus reticularis magnocellularis]. Combining the retrograde axonal transport of rhodamine -isothiocyanate (RITC) after intraocular injection and immunohistofluorescence (fluoresceine isothiocyanate: FITC/5-HT) showed the centrifugal neurons (NIO, ec) to be immunonegative. Serotonin-IR fibers and terminals were found to be very broadly distributed within the brain and were particularly prominent in several structures of the telencephalon (archistriatum pars dorsalis, nucleus taeniae, area parahippocampalis, septum), diencephalon (nuclei preopticus medianus, magnocellularis, nucleus geniculatus lateralis pars ventralis, nucleus triangularis, nucleus pretectalis), mesencephalon-rhombencephalon (superficial layers of the optic tectum, nucleus ectomamillaris, nucleus isthmo-opticus and in most of the cranial nerve nuclei). Comparing the present results with those of previous studies in birds suggests some major serotonin containing pathways in the avian brain and clarifies the possible origin of the serotonin innervation of some parts of the brain. Moreover, comparing our results in birds with those obtained in other vertebrate species shows that the organization of the serotoninergic system in many regions of the avian brain is much like that found in reptiles and mammals.Abbreviations Ad Archistriatum pars dorsalis - alp area interpeduncularis - al ansa lenticularis - Ann nucleus annularis - APH area parahippocampalis - Av archistriatum pars ventralis - AVT area ventralis (Tsai) - bcd brachium conjunctivum descendens - BO bulbus olfactorius - ca commisssura anterior - CDL area corticoidea dorsolateralis - Cer cerebellum - cf fiber layer of the olfactory bulb - cg granular cell layer of the olfactory bulb - co chiasma opticum - ct commissura tectalis - dbc decussatio brachiorum conjunctivorum - DL nucleus dorsolateralis anterior thalami - DLP nucleus dorsolateralis posterior thalami - DM nucleus dorsomedialis thalami - dnt decussatio nervi trochlearis - E ectostriatum - Ec ectopic area of the nucleus isthmo-opticus - EM nucleus ectomamillaris - flm fasciculus longitudinalis medialis - fpl fasciculus prosencephali lateralis - FRL formatio reticularis lateralis mesencephali - FRM formatio reticularis medialis mesencephali - fu fasciculus uncinatus - GCt substantia grisea centralis - GLv nucleus geniculatus lateralis pars ventralis - gr granular cell layer of the cerebellum - HA hyperstriatum accessorium - HD hyperstriatum dorsale - HIS hyperstriatum intercalatus superior - HL nucleus habenularis lateralis - HM nucleus habenularis medialis - Hp hippocampus - HV hyperstriatum ventrale - ICo nucleus intercollicularis - i-flm inter fasciculus longitudinalis medialis - Imc nucleus ishmi pars magnocellularis - Ip nucleus interpeduncularis - Ipc nucleus isthmi pars parvocellularis - LA nucleus lateralis anterior thalami - La nucleus laminaris - LC nucleus linearis caudalis - LHy nucleus lateralis hypothalami - lm lemniscus medialis - LoC locus coeruleus - LPO lobus paraolfactorius - ls lemniscus spinalis - MLd nucleus mesencephalicus lateralis pars dorsalis - mo molecular layer of the cerebellum - MoV nucleus motorius nervi trigemini - Mp magnocellularis preopticus - N neostriatum - NIII nucleus nervi oculomotorii - nIII nervus oculomotorius - NIV nucleus nervi trochlearis - NV nucleus nervi trigemini nV nervus trigeminus - NVII nucleus nervifacialis - nVIII nervus octavus - NIO nucleus isthmo-opticus - om tractus occipitomesencephalicus - OPH hypothalamic periventricular organ - Os nucleus olivaris superior - Ov nucleus ovoidalis - PA paleostriatum augmentatum - Po nucleus pontis - POM nucleus preoticus medialis - PP paleostriatum primitivum - PrV nucleus sensorius principalis nervi trigemini - PT nucleus pretectalis - pu Purkinje cell layer - qf tractus quintofrontalis - Rai nucleus raphe inferior - RasV nucleus raphe superior pars ventralis - ReI recessus infundibularis - Rm nucleus reticularis magnocellularis - Rp nucleus reticularis parvocellularis - RPc nucleus reticularis pontis caudalis - RPO nucleus reticularis pontis oralis - Rt nucleus rotundus - Ru nucleus ruber - S septum - Sac stratum album centrale - SCH stratum cellulare hypothalami - Sgc stratum griseum centrale - Sgf stratum griseum et fibrosum superficiale - Sgfp stratum griseum et fibrosum periventriculare - Sop stratum opticum - SP nucleus subpretectalis - SPC nucleus superficialis parvocellularis - Spl nucleus spiriformis lateralis - Spm nucleus spiriformis medialis - SRt nucleus subrotundus - SuC nucleus subcoeruleus - to tractus opticus - Tn nucleus taeniae - TPc nucleus tegmenti pedunculo-pontinus pars compacta - Tr nucleus triangularis - tsm tractus septomesencephalicus - ttd nucleus et tractus descendens nervi trigemini - Tu nucleus tuberis - Vel nucleus vestibularis lateralis - Vem nucleus vestibularis medialis - Vlt nucleus ventrolateralis thalami - VT nucleus ventrolateralis tegmenti - Zp-flm zona perifasciculus longitudinalis medialis - Zp-NIII zona perinervus oculomotorius     

The thalamic connections with medial area 6 (supplementary motor cortex) in the monkey (macaca fascicularis)

Summary 1. The interrelationship of medial area 6 (supplementary motor area) with the thalamus was investigated by means of anterograde and retrograde tracing methods. Nine monkeys were prepared for autoradiography or histochemistry with the marker HRP conjugated to the lectin wheat germ agglutinin. Three of the monkeys received injections into the precentral cortex for comparison. 2. Previous observations were confirmed that the thalamic relays to the motor areas are organized as crescent-shaped lamellae which transgress cytoarchitectonic boundaries. The thalamic VA-VL complex receiving fibres from areas 4 and medial area 6 also sends fibres to these same areas. 3. The thalamic relay to medial area 6 comprised the following subdivisions: VLo, VLc, area X of Olszewski, VLm and, to a smaller extent VA. 4. Labeling (mostly anterograde only) was also prominent in some thalamic compartments outside the motor thalamus: R, CL, CM-Pf, MD, LP, PULo. 5. It was noted that rostral and caudal injections into the medial area 6 resulted in different thalamic labeling: The rostral portion was found to be related mainly with VApc, area X and VLc, the central portion with VLo, and the caudal portion with VLc/VLo. This structural inhomogeneity may reflect also a functional rostro-caudal differentiation of the medial area 6. 6. The thalamic territory projecting to the precentral cortex is separate from the above relay and includes principally VPLo. 7. The present anatomical labeling study is in agreement with the conclusion of Schell and Strick (1984) that the SMA, especially its central portion, is an important target of basal ganglia outflow via the thalamic relay VLo. In addition consistent labeling was also found in thalamic subdivisions (area X, VLc) which had been found to receive cerebellar fibres.Abbreviations AD Nucleus anterior dorsalis - AM Nucleus anterior medialis - AV Nucleus anterior ventralis - ARG Autoradiography - CL Nucleus centralis lateralis - CM Centre median nucleus - Comm. post. Commissura posterior - CLS Nucleus centralis superior lateralis - For Fornix - GM Nucleus geniculatus medialis - In p.c. Nucleus interstitialis of the posterior commissure - LD Nucleus lateralis dorsalis - Li Nucleus limitans - LP Nucleus lateralis posterior - MDmc Nucleus medialis dorsalis, pars magnocellularis - MDmf Nucleus medialis dorsalis, pars multiformis - MDpc Nucleus medialis dorsalis, pars parvocellularis - NRmc Nucleus ruber magnocellularis - NRpc Nucleus ruber parvocellularis - Pcn Nucleus paracentralis - Pf Nucleus parafascicularis - Pul.i. Nucleus pulvinaris inferior - Pul.l. Nucleus pulvinaris lateralis - Pul.m. Nucleus pulvinaris medialis - Pul.o. Nucleus pulvinaris oralis - R Nucleus reticularis thalami - SMA Supplementary motor area - STh Nucleus subthalamicus - VAmc Nucleus ventralis anterior, pars magnocellularis - VApc Nucleus ventralis anterior, pars parvocellularis - VLc Nucleus ventralis lateralis, pars caudalis - VLm Nucleus ventralis lateralis, pars medialis - VLo Nucleus ventralis lateralis, pars oralis - VLps Nucleus ventralis lateralis, pars postrema; - VPI Nucleus ventralis posterior inferior - VPLo Nucleus ventralis posterior lateralis, pars oralis - VPM Nucleus ventralis posterior medialis - WGA-HRP Horseradish peroxidase conjugated to the lectin wheat germ agglutinin; - X Area X - ZI Zona incerta     

The topology of the thalamo-cortical projections in the marmoset monkey (Callithrix jacchus)

Summary This paper addresses the question of a general topological principle of thalamo-cortical projections. In the lissencephalic primate brain of the common marmoset (Callithrix jacchus), large injections of horseradish peroxidase were made in various parts of the neocortex. These injections were placed in different animals and hemispheres along various caudo-rostral and mediolateral gradients. Labelled cells in the thalamus were plotted and the labelling-zones resulting from several injections along a medio-lateral and two caudo-rostral cortical vectors were drawn into semi-schematic thalamic maps. These composite maps reveal a topological organization of the whole thalamo-cortical projection. The thalamic representation of the caudo-rostral and mediolateral gradients indicate a rotation of the posterior relative to the anterior thalamus. An attempt is made to relate the organization of the thalamo-cortical projection to the development of the thalamus and the cortex. The cortex is divided into concentric zones around the sensory-motor and insular cortex. The thalamus is divided into corresponding projection zones. The topology of thalamo-cortical connections can then be regarded as a consequence of corresponding thalamic and cortical growth gradients. This is not only consistent with the general thalamo-cortical topology and the inversion of maps from thalamus to cortex, but also explains the continuity and overlap of thalamic projection zones in the pulvinar to widely separated cortical areas as the parietal, temporal and frontal association cortex.Abbreviations AD Nucleus anterior dorsalis thalami - AM Nucleus anterior medialis thalami - AV Nucleus anterior ventralis thalami - CeD Nucleus centralis dorsalis thalami - CeL Nucleus centralis lateralis thalami - CeM Nucleus centralis medialis thalami - CeMe Centre median - GLD Corpus geniculaturn laterale dorsale - GLV Corpus geniculatum laterale ventrale - GM Corpus geniculatum mediale - LD Nucleus lateralis dorsalis thalami - Li Nucleus limitans thalami - LP Nucleus lateralis posterior thalami - MD Nucleus medialis dorsalis thalami - Pf Nucleus parafascicularis thalami - PvT Nucleus paraventricularis thalami - Pul Pulvinar inferior - PuIP Pulvinar inferior posterior - PuL Pulvinar lateralis - PuM Pulvinar medialis - PuO Pulvinar oralis - Re Nucleus Reuniens - Sg Nucleus suprageniculatus - VA Nucleus ventralis anterior - VAMg Nucleus ventralis anterior magnocellularis - VL Nucleus ventralis lateralis - VP Nucleus ventralis posterior - VPL Nucleus ventralis posterior lateralis - VPM Nucleus ventralis posterior medialis     

Topographical and topological organization of the thalamocortical projection to the striate and prestriate cortex in the marmoset (Callithrix jacchus)

Summary In eleven hemispheres of nine marmoset monkeys (Callithrix jacchus), we have investigated the thalamo-cortical organization of the projections from the pulvinar to the striate and prestriate cortex. In each experiment, single or multiple injections of various retrograde fluorescent tracers were injected into adjacent regions or areas. In two experiments, horseradish peroxidase (HRP) was injected into the lateral geniculate nucleus (LGN) and the lateral pulvinar, respectively. The results show that the thalamo-cortical projection from LGN to striate cortex and from pulvinar to the prestriate cortex are similarly organized, but the geniculo-striate projection is more precise than the pulvinar-prestriate projection. The pulvinar-prestriate projection is topographically organized and preserves topological neighbourhood relations. Projection zones to the various visual areas are concentrically wrapped around each other. The projection zone to area 18 constitutes a central core region. It begins ventro-laterally in PuL where the pulvinar is in contact with the LGN. This contact zone we called the hilus region of the pulvinar. The area 18-projection zone stretches as a central cone into the posterior pulvinar through PuL and into PuM. It is surrounded by the projection zone to the posterior belt of area 19 and this in turn is surrounded by the projection zone to the anterior belt of area 19. The projection zones to area 19 are then surrounded medially and dorsally by zones projectiong to the temporal and parietal association cortex, respectively. The projection zone to area MT is located medio-ventrally in the posterior pulvinar (PuIP and surrounding nuclei) and coincides with a densely myelinated region. Area 17 also receives input from the pulvinar but probably predominantly in the region of the central visual field. The pulvinar zone projecting to area 17 is located ventrolaterally from the central core region projecting to area 18 and is contiguous laterally with the LGN. If the positions of the vertical and the horizontal meridian in the pulvinar correspond to those in the respective cortical projection zones, a second order visual field representation such as found in area 18, with the horizontal meridian split at an excentricity of about 7–10°, can also be recognized in the pulvinar.Abbreviations A Subcortical nuclei and subnuclei, cf. — Stephan et al. (1980) - AD Nucleus anterior dorsalis thalami - AV Nucleus anterior ventralis thalami - CeD Nucleus centralis dorsalis thalami - CeL Nucleus centralis lateralis thalami - CeMe Centrum medianum thalami - CoS Colliculus superior - FRPO Formatio reticularis pontis, pars oralis - GM Corpus geniculatum mediale - IBCI Nucleus interstitialis brachii colliculi inferioris - LGN Corpus geniculatum laterale dorsale - vLGN Corpus geniculatum laterale ventrale - LD Nucleus lateralis dorsalis thalami - LI Nucleus limitans thalami - LP Nucleus lateralis posterior thalami - MD Nucleus medialis dorsalis thalami - OL Nucleus olivaris superior lateralis - OM Nucleus olivaris superior medialis - Pbg Nucleus parabigeminalis - Pul Pulvinar inferior; PulP Pulvinar inferior posterior - PuL Pulvinar lateralis - PuM Pulvinar medialis - PuO Pulvinar oralis - RT Nucleus reticularis thalami - Sg Nucleus suprageniculatus - VA Nucleus ventralis anterior thalami - VL Nucleus ventralis lateralis thalami - VPL Nucleus ventralis posterior lateralis thalami - VPM Nucleus ventralis posterior medialis thalami - IV Nucleus nervi trochlearis - B Cortical areas and subareas, (after Spatz 1977a; Spatz et al. 1987 Allman and Kaas 1975): - 17 Area striata (V I) - 18 Area 18 (V II) - 19DI Area 19 dorso-intermediate - 19DL Area 19 dorso-lateral - 19DM Area 19 dorso-medial - 19M Area 19 medial - 19V Area 19 ventral - MT Middle temporal area     

Axonal patterns and sites of termination of cat superior colliculus neurons projecting in the tecto-bulbo-spinal tract

Summary Horseradish peroxidase was injected in the somata or axons of neurons located in the intermediate and deep layers of the superior colliculus. A group of 34 neurons with physiologically identified projection in the predorsal bundle (tectobulbo-spinal neurons, TBSNs) and two commissural tecto-tectal neurons were characterized with regard to soma-dendritic profiles, axon trajectories, collateral branching, and terminations.TBSNs belong to the class of large, multipolar, wide field neurons. They send axons through the deep white layer without generating local collaterals. Prior to decussation, all TBSNs bifurcate into an ascending branch which reaches the caudal diencephalon, and a main axon descending to the medulla or spinal cord. Regularly spaced collaterals supply a variety of structures at all rostro-caudal levels. In the midbrain, preterminal and terminal ramifications are present in the medial and lateral reticular tegmentum, in the central grey (including its supraoculomotor zone), in the nuclei of Cajal and Dark-schewitsch and in the medial aspects of the prerubral area and the fields of Forel. Rhombencephalic targets of TBSNs include the medial pontine and bulbar reticular formation, the abducens nucleus, the nucleus reticularis tegmenti pontis and the nucleus prepositus hypoglossi. An increased density of terminal ramifications was found in several brain stem regions related to the control of eye and head movements. The widespread connections of each individual TBSN suggest that neurons of this type may provide a spatio-temporal pattern of facilitation which promotes rapid orientation of eyes, head and body towards the contralateral hemifield but does not specify the details of movement to be executed.Abbreviations c contralateral - CP commissura posterior - CS colliculus superior - CT corpus trapezoideum - F campus Foreli - FA funiculus anterior - FRM formatio reticularis medullae - FRP formatio reticularis pontis - Fpd fasciculus predorsalis - MLF fasciculus longitudinalis medialis - N substantia nigra - NC nucl. cuneatus - NIC nucl. interstitialis Cajal - NRT nucl. reticularis tegmenti pontis - NV nucl. vestibularis - pB nucl. parabigeminalis - R nucl. ruber - SGC substantia grisea centralis - TO tractus opticus - 6N nucl. nervi VI     

Origin and fine structure of substance P-containing nerve terminals in the facial nucleus of the rat: an immunohistochemical study

Summary The distribution, origin and fine structure of substance P-like immunoreactive (SPI) nerve terminals in the facial nucleus of the rat were investigated by means of immunocytochemistry. SPI-terminals were concentrated in the intermediate and dorsal subnuclei of the facial nucleus. Hemi-transection of the brainstem just rostral to the facial nucleus or at the most caudal level of the medulla oblongata did not cause any change of SPI-terminals in the facial nucleus. Electrical destruction of the various parts of the medulla oblongata clearly demonstrated that SPI-terminals in the intermediate subnucleus were supplied contralaterally from the SPI-neurons in the dorsomedial part of the medullary reticular formation. Most of the SPI-terminals (85%) in the intermediate subnucleus of the facial nucleus were observed to make asymmetric synaptic contacts with large dendrites (mean diameter; 1.26 m). It was supposed that the contact sites are located on proximal parts of the dendrite. A few SPI-terminals (6%) formed axo-somatic contacts with large perikarya filled with numerous cytoplasmic organelles.Abbreviations used in Figures A n. ambiguus - AP area postrema - C n. cuneatus - Cod n. cochlearis dorsalis - Cov n. cochlearis ventralis - CU n. cuneiformis - FLM fasciculus longitudinalis medialis - G n. gracilis - MRF midbrain reticular formation - nts n. tractus solitarius - nVsp n. tractus spinalis nervi trigemini - nVII n. originis nervi facialis - nX n. originis dorsalis vagi - nXII n. originis nervi hypoglossi - OI n. olivaris inferior - rfl the ventro-lateral part of the caudal medullary reticular formation - rfm the dorso-medial part of the medullary reticular formation - RL n. reticularis lateralis - RM n. raphe magnus - rmg n. reticularis magnocellularis - RO n. raphe obscurus - sgc substantia grisea centralis - Vl n. vestibularis lateralis - Vm n. vestibularis medialis - Vsp n. vestibularis spinalis     

大鼠下丘的非听性传出投射

为了全面了解大白鼠下丘的非听性传出投射及其起源细胞在下丘的分布情况,作者分别向下丘、丘脑和延髓注入WGA-HRP,作顺行或逆行追踪研究,结果如下: 下丘的非听性传出投射分布较广,在间脑和脑干终止于12个核团和地区,包括同侧的桥核背外侧部、臂旁外侧核、中脑中央灰质、中脑外侧被盖核、上丘联合核、顶盖前区、丘脑网状核、膝上核、丘脑后核、丘脑腹核、未定带和对侧楔束核的背外侧部。上述非听性传出投射的起源细胞分布于下丘除中央核以外的其他亚核。     

Quantitative studies on the supraoptic nucleus in the rat. II. Afferent fiber connections

Summary A quantitative electron microscopic study of synaptic terminal degeneration was performed in the supraoptic nucleus (NSO) after a variety of major transections or ablations, destroying or interrupting in different combinations the afferent pathways known from earlier and own light microscopic degeneration studies. Solutions of a set of equations, expressing the percentage degenerations in synaptic profiles after different combinations in which the several pathways are interrupted by the various interferences, enabled the authors to give the following percentage numbers for afferent synapses from different sources.32.7% of supraoptic afferents originate from the brain stem probably representing the monoaminergic innervation of this nucleus. The medial basal hypothalamus (21.0%), amygdala (13.5%), septum (13.5%), hippocampus (8.5%) and olfactory tubercle and further rostral cortical region (17.0%) are the other main sites of origin of supraoptic nucleus afferents. There are no supraoptic afferents from the optic nerve, superior cervical ganglion or fimbria hippocampi.Abbreviations A nucleus accumbens - AB nucleus amygdaloideus basalis - AC nucleus amygdaloideus centralis - AL nucleus amygdaloideus lateralis - AM nucleus amygdaloideus medialis - ATV area tegmenti ventralis (Tsai) - C caudate-putamen - CA commissura anterior - CC corpus callosum - CFV commissura fornicvis ventralis - CO chiasma opticum - CP commissura posterior - D nucleus tractus diagnolis - DM nucleus dorsomedialis - DS decussationes supraoptica - F columna fornicis - FH fimbria hippocampi - FLM fasciculus longitudinalis medialis - FP fornix praecommissuralis - FS fornix superior - G globus pallidus - GD gyrus dentatus - HI hippocampus - IC capsula interna - IP nucleus interpeduncularis - LM lemniscus medialis - M medial forebrain bundle (MFB) - MM nucleus medialis thalami, pars medialis - NA nucleus arcuatus - R nucleus rhomboideus - RE nucleus reuniens - RV nucleus ruber - S stria medullaris thalami - SD nucleus dorsalis septi - SF nucleus fimbrialis septi - SG substantia grisea centralis - SL nucleus lateralis septi - SM nucleus medialis septi - SN substantia nigra - ST nucleus interstitialis striae terminalis - T tractus olfactorius lateralis - TD tractus diagonalis (Broca) - TO tractus opticus - TSTH tractus striohypothalamicus - TU tuberculum olfactorium - VM nucleus ventromedialis