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Sensory neurons with somata in the antennae of the moth, Manduca sexta, make synapses in the antennal lobes of the brain. These lobes develop during metamorphosis of the pupa to the adult while the antennae themselves develop and send presumably cholinergic sensory fibers into the lobes. Levels of acetylcholine, choline acetyltransferase, and acetylcholinesterase rise dramatically in the lobes as sensory axons grow from the antennae to the lobes through the antennal nerves. An [¹²⁵I]α-bungarotoxin-binding activity, which may represent ACh-receptors, develops in the lobes with a time course different from that of the other cholinergic components, rising gradually throughout metamorphosis. This activity is specific to nervous tissue and is blocked by cholinergic agents (carbamylcholine, atropine, curare, and nicotine). Levels of acetylcholine, choline acetyltransferase, and acetylcholinesterase, but not of toxin-binding activity, are greatly reduced in lobes deafferented by amputation of developing antennae.     

Chromatophore motoneurons in the brain of the squid, Lolliguncula brevis: a HRP study

The location of the motoneuron somata controllingg activity of the chromatophore muslces was studied in the squid Lollinguncula brevis. Retrograde transport of horseradish peroxidase from injection sites in the skin or in the mantle muscle established that the chromatophore motoneurons are situated in the subesophageal mass of the brain while at least some of the mantle muscle motoneurones are in the stellate ganglia. Motoneurons to chromatophores in the mantle have their somata in the posterior subesophageal mass, mainly in the chromatophore or fin lobes. Motoneurons to chromatophores in the head are located in the anterior pedal lobes and those to the chromatophores in the arms project mainly from the anterior chromatophore lobes. However, some neurons in the posterior chromatophore lobes project to the head or arm regions. A few cells in both the anterior and posterior chromatophore lobes project contralaterally. Somata in other lobes of the subesophageal mass are also labelled by injections in the skin or in the mantle muscle. Evidence presented here suggests that some of the neurons labelled outside the chromatophore lobes are chromatophore motoneurons.     

Changes in levels of phosphorus metabolites in temporal lobes of drug-naive schizophrenic patients.

OBJECTIVE: The authors examined phospholipids and high-energy phosphorus metabolism in the temporal lobes of drug-naive schizophrenic patients. METHOD: In vivo 31P magnetic resonance spectroscopy was performed on 17 first-episode, drug-naive schizophrenic patients and 17 age- and gender-matched healthy subjects. RESULTS: Patients showed higher levels of phosphodiesters and lower levels of phosphomonoesters than the comparison group. Phosphocreatine levels were increased in the left temporal lobes of patients. CONCLUSIONS: The results suggest disturbed membrane phospholipid metabolism in both temporal lobes and decreased energy demands in the left temporal lobes of drug-naive schizophrenic patients.     

Cognitive decline in AD and mild cognitive impairment is associated with global brain damage

OBJECTIVE: To investigate the relationships between structural damage in the whole brain, the temporal lobes, and the frontal lobes and cognitive decline at old age. The authors hypothesized that widespread brain damage as quantified using magnetization transfer imaging (MTI) is related to global cognitive decline, whereas regional damage to the temporal lobes is related to memory impairment, and regional damage to the frontal lobes is related to executive dysfunctioning. METHODS: Cognitive function of 22 patients with probable AD, 13 patients with mild cognitive impairment (MCI), and 28 elderly controls was assessed using an extensive neuropsychological test battery. Structural damage in the whole brain, the temporal lobes, and the frontal lobes was estimated using volumetric MTI analysis. Associations between MTI measures and neuropsychological tests were investigated using Pearson correlation analysis. RESULTS: MTI measures of the whole brain, as well as the temporal and the frontal lobes, were strongly associated with global cognitive deterioration and impairment in memory, orientation, language, praxis, gnosis, and executive functioning. However, there were no specific cognitive correlates of regional brain damage to the temporal and frontal lobes. CONCLUSIONS: Using whole brain volumetric magnetization transfer imaging, the authors demonstrated that cognitive decline in patients with mild cognitive impairment and AD is associated with widespread structural brain damage. As there were no specific relationships between regional brain damage and impairment of specific cognitive functions, pathology in AD and mild cognitive impairment is much more generalized than was expected.     

Acute infantile encephalopathy predominantly affecting the frontal lobes

To establish a novel subtype of acute infantile encephalopathy, the clinical and radiologic features of nine infants with acute encephalopathy involving the bilateral frontal lobes were examined. These patients had convulsive status epilepticus with hyperpyrexia followed by a prolonged impairment of consciousness for 2-20 days. After the recovery of consciousness, all the patients manifested regression of verbal function and lack of spontaneity. Some of them also exhibited stereotypic movements, instability of mood, or catalepsy. Transient postictal edema in both frontal lobes was suggested by diffusion-weighted magnetic resonance imaging. Attenuated cerebral perfusion in the frontal lobes was demonstrated by single-photon emission computed tomography at the tenth day after onset or subsequently. Serial studies disclosed atrophic changes in the frontal lobes. All patients manifested regression or retardation of motor and verbal functions. The recovery of intellectual deficit was slower and less prominent than that of motor dysfunction. These unique features suggest that the frontal lobes are the focus of this novel subtype of acute encephalopathy, which we propose to call acute infantile encephalopathy predominantly affecting the frontal lobes.     

Measurements of the frontal and prefrontal lobe volumes by three dimensional magnetic resonance imaging scan--III. Analysis of sex differences with advanced age

To determine whether there is sex difference in the growth of the frontal and prefrontal lobes, we quantitatively measured the volume of these lobes by three dimensional (3-D) MRI in healthy 12 males (5 months to 39 years) and six females (1 year 11 months to 27 years). The left and right lobes were studied separately. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. In males, the left to right ratio (L/R ratio) of the frontal and prefrontal lobes increased with age. On the contrary, in females, L/R ratio of the frontal and prefrontal lobes showed no significant change with advancing age. These results highlighted sex-specific maturational changes of the frontal and prefrontal lobes and suggested that quantitative data on the frontal and prefrontal lobe are important in interpreting brain abnormalities in children with developmental disorders.     

Quantitative shape analysis of the temporal and prefrontal lobes of schizophrenic patients: a magnetic resonance image study

In a recent quantitative neuroimaging study, the authors reported significant reduction in the gray matter volume of both temporal lobes of schizophrenic (SC) patients. In order to better elucidate the nature of this finding (i.e., diffuse vs. focal), we analyzed the shape of the temporal lobes of 17 SC patients and an equal number of age-sex matched controls. Our shape analysis was able to discriminate between a significant number of SC and control patients based on the Fourier harmonic amplitudes of both the middle and posterior levels of the temporal lobes. These results are consistent with bilateral focal or multifocal distortions of the temporal lobes of SC patients. A similar shape analysis of the prefrontal lobes showed no significant conformational differences between the groups. The basis of this quantitative shape analysis (the Fourier expansion series) and the method by which it can be applied are explained in detail.     

Crayfish brain interneurons that converge with serotonin giant cells in accessory lobe glomeruli

Freshwater crayfish have well-developed olfactory systems with an array of receptors that project exclusively to areas in the brain that are functionally specialized for the processing of odors. The accessory lobes are large bilateral areas of neuropil that are anatomically associated with the olfactory lobes. The accessory lobes receive no primary afferents and do not contain the endings of motor efferents; thus, their role in olfaction is still obscure. Intracellular dye filling of interneurons in the deutocerebral commissure in the crayfish brain has shown that they end bilaterally in glomeruli in the accessory lobes, have cell somata in a dorsal cluster medial to the olfactory lobes, and have unilateral projections to the deutocerebral commissure neuropil. Each deutocerebral commissure interneuron has only 6 to 15 output glomeruli in each accessory lobe and does not share glomeruli with other deutocerebral commissure interneurons. The deutocerebral commissure interneurons converge with the dorsal giant serotonin neurons in the accessory lobe glomeruli. Deutocerebral commissure interneurons can be separated into classes according to their projections to the protocerebrum, central body, and deutocerebrum. Physiological responses of the deutocerebral commissure interneurons following photic stimulation of the eyes and electrical stimulation of the second antennae lead to the conclusion that the deutocerebral commissure represents an input to the accessory lobes from the protocerebral neuropils and that visual and tactile inputs are included in the processing performed in the accessory lobes. © 1995 Wiley-Liss, Inc.     

Frontal lobe functions

The frontal lobes constitute two thirds of the human brain, yet the functions performed by them remained mysterious for a long time. Apart from their well-known involvement in motor function and language, little was previously known about the functions of the frontal lobes. Recent advances have uncovered important roles for the frontal lobes in a multitude of cognitive processes, such as executive function, attention, memory, and language. The importance of the frontal lobes in processes underlying affect, mood, personality, selfawareness, as well as social and moral reasoning, is also a renewed area for research. This article focuses on recent advances in understanding frontal lobe functions.     

Magnetic resonance imaging in relation to EEG epileptic foci in tuberous sclerosis

In 20 patients with tuberous sclerosis (TS), who were sequentially treated for epilepsy at our clinic, the high signal lesions in the cerebral cortex and subcortex detected on T2 weighted magnetic resonance imaging (MRI) were compared with the interictal EEG findings. In four cases who showed a unilateral distribution of the MRI lesions, there was a good correlation between the laterality of the affected lobes and the localization of the EEG epileptic foci. Thirteen cases with more than four affected lobes in both hemispheres also showed bilateral epileptic foci on EEG. The MRI lesions in the occipital lobes showed the best correlation with the EEG epileptic foci, while the worst correlation was seen in the frontal lobes. In addition, the cases with four or more affected lobes without laterality on MRI are more likely to show bilateral synchronization on EEG. The prognosis of epilepsy in these cases was found to be rather poor.     

Corticotrophin-Releasing Hormone Stimulates Neurohypophyslal Hormone Release through an Interaction with the Intermediate Lobe of the Pituitary

Corticotrophin-releasing hormone is found co-localized with oxytocin in the magnocellular-neurohypophysical system but its function in this context is unknown. We tested its effects on neurohypophysical hormone secretion in vitro , in the presence and absence of the intermediate lobe of the pituitary. Corticotrophin-releasing hormone caused significant, calcium-dependent secretion of oxytocin and vasopressin from neural lobes in contact with intermediate lobes, i.e. neurointermediate lobes. This effect was inhibited by the dopamine agonist, bromocriptine. Corticotrophin-releasing hormone had no effect on isolated neural lobes in the absence of the intermediate lobe, but α- and γ-melanocyte-stimulating hormone produced an increase in secretion that was comparable in pattern and magnitude to the effect of corticotrophin-releasing hormone on neurointermediate lobes. These findings suggest that corticotrophin-releasing hormone released with oxytocin may act in a paracrine fashion to stimulate release of intermediate peptides which, in turn, can directly evoke release of oxytocin and vasopressin from neural lobe terminals.     

抑郁症患者SPECT研究

目的 探讨抑郁症脑血流灌注的特点及与临床症状的相关性。方法 开放式收集门诊及住院诊断为抑郁症患者37例,进行治疗前后的^99mTc-双半胱乙脂（ECD）单光子发射型计算机断层扫描（SPECT）技术,测量患者治疗前后脑血流灌注（rCBF）显像,半定量测定rCBF,并与12例正常对照者比较。结果 37例抑郁症患者双侧额叶、双侧颞叶、双侧顶叶,双侧枕叶、左基底核有脑低灌注现象。治疗后临床康复者各部位脑灌注明显改善,差异有显著性（P〈0.05）。结论 抑郁症患者存在额叶、颡叶、顶叶及枕叶多区域的脑血流低灌注,其中以左侧较为明显,治疗后明显改善。     

Response of neuropeptides and neurotransmitter binding sites in the retina and brain of the developing chick to reduced visual input

The effect of 17 days of monocular suture of eyelids of day-old chicks upon levels of neuropeptides and high affinity binding sites was studied. A significant reduction of met-enkephalin, but not of substance P or neurotensin, was observed in the retina of the eye receiving dim and unpatterned light. Retinal muscarinic, dopaminergic, opiate, and benzodiazepine receptors appeared unaltered by the experimental procedure. Levels of neuropeptides were not significantly changed in optic lobes contralateral to and innervated by the sutured eyes relative to the optic lobes receiving afferentation from the open eyes. Seventeen days after unilateral enucleation of new-hatched chicks, the neuropeptide content of the smaller denervated optic lobes did not differ from that of the lobes receiving an intact neuronal input.     

Neuronal assemblies of the Drosophila mushroom body

The mushroom body (MB) of the insect brain has important roles in odor learning and memory and in diverse other brain functions. To elucidate the anatomical basis underlying its function, we studied how the MB of Drosophila is organized by its intrinsic and extrinsic neurons. We screened for the GAL4 enhancer-trap strains that label specific subsets of these neurons and identified seven subtypes of Kenyon cells and three other intrinsic neuron types. Laminar organization of the Kenyon cell axons divides the pedunculus into at least five concentric strata. The alpha', beta', alpha, and beta lobes are each divided into three strata, whereas the gamma lobe appears more homogeneous. The outermost stratum of the alpha/beta lobes is specifically connected with a small, protruded subregion of the calyx, the accessory calyx, which does not receive direct olfactory input. As for the MB extrinsic neurons (MBENs), we found three types of antennal lobe projection neurons, among which two are novel. In addition, we resolved 17 other types of MBENs that arborize in the calyx, lobes, and pedunculus. Lobe-associated MBENs arborize in only specific areas of the lobes, being restricted along their longitudinal axes, forming two to five segmented zones in each lobe. The laminar arrangement of the Kenyon cell axons and segmented organization of the MBENs together divide the lobes into smaller synaptic units, possibly facilitating characteristic interaction between intrinsic and extrinsic neurons in each unit for different functional activities along the longitudinal lobe axes and between lobes. Structural differences between lobes are also discussed.     

Age-related changes in frontal and temporal lobe volumes in men: a magnetic resonance imaging study

BACKGROUND: Imaging and postmortem studies provide converging evidence that, beginning in adolescence, gray matter volume declines linearly until old age, while cerebrospinal fluid volumes are stable in adulthood (age 20-50 years). Given the fixed volume of the cranium in adulthood, it is surprising that most studies observe no white matter volume expansion after approximately age 20 years. We examined the effects of the aging process on the frontal and temporal lobes. METHODS: Seventy healthy adult men aged 19 to 76 years underwent magnetic resonance imaging. Coronal images focused on the frontal and temporal lobes were acquired using pulse sequences that maximized gray vs white matter contrast. The volumes of total frontal and temporal lobes as well as the gray and white matter subcomponents were evaluated. RESULTS: Age-related linear loss in gray matter volume in both frontal (r = -0.62, P<.001) and temporal (r = -0.48, P<.001) lobes was confirmed. However, the quadratic function best represented the relationship between age and white matter volume in the frontal (P<.001) and temporal (P<.001) lobes. Secondary analyses indicated that white matter volume increased until age 44 years for the frontal lobes and age 47 years for the temporal lobes and then declined. CONCLUSIONS: The changes in white matter suggest that the adult brain is in a constant state of change roughly defined as periods of maturation continuing into the fifth decade of life followed by degeneration. Pathological states that interfere with such maturational processes could result in neurodevelopmental arrests in adulthood.     

Improved proper name recall by electrical stimulation of the anterior temporal lobes

People's names have an embarrassing propensity to be forgotten. This problem is exacerbated by normal aging and by some kinds of dementia. As evidence from neuroimaging and neuropsychology suggest that portions of the anterior temporal lobes play a role in proper name retrieval, we hypothesized that transcranial direct current stimulation (tDCS), a technique that modulates neural transmission, to the anterior temporal lobes would alter the retrieval of proper names. Fifteen young adults received left anodal, right anodal, or sham stimulation of the anterior temporal lobes while naming pictures of famous individuals and landmarks. Right anterior temporal lobe stimulation significantly improved naming for people but not landmarks. These findings are consistent with the notion that the anterior temporal lobes are critically involved in the retrieval of people's names.     

Quantitative autoradiographic localization of [125I]alpha-bungarotoxin binding sites in the honeybee brain

Binding sites for the nicotinic acetylcholine receptor antagonist, [125I]alpha-bungarotoxin, were localized in the honeybee brain by in vitro autoradiography. Highest binding site densities were localized in the suboesophageal ganglion, the optic tubercles, optic lobes medulla and lobula, antennal lobes, dorsal lobes and the alpha-lobes of the mushroom bodies. The distribution pattern of these putative nicotinic acetylcholine receptors suggests that acetylcholine is involved in several sensory pathways and in central information processing in the honeybee brain.     

Anatomical and functional abnormalities of central nervous system in autistic disorder: a MRI and SPECT study

We present a study of anatomical and functional abnormalities of central nervous system (CNS) from patients with autistic disorder (AD); magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT) were used for the investigation. The population studied was composed of 24 patients, 15 (62.5%) males and 9 (17.5%) females, mean age 9 years. MRI was performed in all patients and SPECT was performed in 19 patients; 75% (n=18) of patients had anatomical abnormalities and all patients that realized SPECT had functional abnormalities. Anatomical abnormalities were preferentially noted in corpus callosum (25%), septum pellucidum (15.63%), cerebral ventricles (12.55%), cerebellum (9.38%), temporal lobes (6.25%), occipital lobes (6.25%) and hippocampus (6.25%). Functional abnormalities predominated in frontal lobes (53.13%), temporal lobes (28.13%), parietal lobes (15.63%) and basal ganglia (3.13%). However, anatomical and functional abnormalities of CNS are not priorities for diagnosis, which should have always clinical validation.     

Coronal reconstruction images of glucose metabolism in Alzheimer's disease.

Coronal images of position emission tomography (PET) by 18F-labelled deoxyglucose reconstructed from interpolated scan in Alzheimer's disease clearly indicated suppression of glucose metabolism in the parietal lobe and lateral part of the temporal lobes, compared to normal controls. The medial part of the temporal lobes in Alzheimer's disease did show a mildly lower glucose metabolic rate than that in normal controls; therefore it is suggested that the parietal and lateral parts of the temporal lobes are primary affected regions in Alzheimer's disease, not the medial part of the temporal lobe, including the hippocampus.     

Electrical responses and synaptic connections of giant serotonin-immunoreactive neurons in crayfish olfactory and accessory lobes

Five pairs of identified 5HT-IR cells in the deutocerebrum of the crayfish Cherax are known to have their synaptic endings in the accessory and olfactory lobes. Two of these cells, one on each side of the brain, are significantly larger than the others. Dye fills of these “giant” cells reveal each to be an interneuron with its branches confined to, but distributed throughout, the olfactory and accessory lobes on the side of the brain ipsilateral to its cell body and with no branches to the contralateral side. Intracellular recordings from the giant cells were made while stimulating the olfactory afferents and tracts within the brain in an attempt to discover the inputs and outputs to the cells. Electrical stimulation of chemoreceptor sensilla on the outer branch of the antennule does not excite the giant 5HT neurons. Focal extracellular electrical stimulation of the olfactory globular tract containing the axons of projection neurons from the olfactory and accessory lobes produces excitatory synaptic potentials and action potentials in the giant cells. Focal extracellular electrical stimulation of the deutocerebral commissure, the axons of which terminate in the glomeruli of the accessory lobes, also results in excitation of the giant cells. We conclude that the input to the giant cells is via axons in the deutocerebral commissure and collaterals from the projection neurons, ending in the glomeruli of the accessory lobes. The output of the giant cells is to the olfactory lobes, where it may serve to modulate olfactory signals.