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At least 19 recordsLinked to original sources
PubMed2006

Temporal lobe gray matter in schizophrenia spectrum: a volumetric MRI study of the fusiform gyrus, parahippocampal gyrus, and middle and inferior temporal gyri.

Although several brain morphologic studies have suggested abnormalities in the temporal regions to be a common indicator of vulnerability for the schizophrenia spectrum, less attention has been paid to temporal lobe structures other than the superior temporal gyrus or the medial temporal region. In this study, we investigated the volume of gray matter in the fusiform gyrus, the parahippocampal gyrus, the middle temporal gyrus, and the inferior temporal gyrus using magnetic resonance imaging in 39 schizotypal disorder patients, 65 schizophrenia patients, and 72 age and gender matched healthy control subjects. The anterior fusiform gyrus was significantly smaller in the schizophrenia patients than the control subjects but not in the schizotypal disorder patients, while the volume reduction of the posterior fusiform gyrus was common to both disorders. Volumes for the middle and inferior temporal gyri or the parahippocampal gyrus did not differ between groups. These findings suggest that abnormalities in the posterior region of the fusiform gyrus are, as have been suggested for the superior temporal gyrus or the amygdala/hippocampus, prominent among the temporal lobe structures as a common morphologic substrate for the schizophrenia spectrum, whereas more widespread alterations involving the anterior region might be associated with the development of full-blown schizophrenia.

Adult↗
PubMed2004

Morphological differences of intraneuronal ubiquitin-positive inclusions in the dentate gyrus and parahippocampal gyrus of motor neuron disease with dementia.

Semiquantitative morphological analysis of cerebral intraneuronal ubiquitin-positive tau-negative inclusions, a pathologic marker for motor neuron disease with dementia (MND-D), was performed in the dentate gyrus and parahippocampal gyrus of 20 clinicopathologically confirmed patients with MND-D. The forms of the inclusions were tentatively classified into three types: (i) C-type, consisting of relatively large and intensely stained crescent or circular structures; (ii) L-type, showing fine linear structures around the nuclei; and (iii) G-type, showing faintly stained granular structures. The frequencies of the C-type, L-type and G-type was 0.5-9.3%,0.2-6.5% and 0-6.6% of dentate granule cells, respectively. In contrast to the dentate gyrus, almost all inclusions showed either the C-type or L-type form in the parahippocampal gyrus. A positive correlation was noted only between incidences of C-type inclusion of the dentate gyrus and that of the parahippocampal gyrus (r = 0.69, P < 0.05). The morphological differences of the inclusions probably reflect different stages of their formation.

Adult↗
PubMed1995

Magnetic resonance imaging volumetric measurements of the superior temporal gyrus, hippocampus, parahippocampal gyrus, frontal and temporal lobes in late paraphrenia.

Quantified magnetic resonance measurements were made of superior temporal gyrus, parahippocampal gyrus, hippocampal, frontal and temporal lobe volumes and of the planar area of the thalamus and basal ganglia structures in 47 late paraphrenic patients and 33 healthy elderly controls. The late paraphrenics were divided into 31 schizophrenics and 16 patients with delusional disorder according to ICD-10 guidelines. Patients with delusional disorder tended to have smaller left temporal volumes compared with control subjects and patients with schizophrenia, but this difference failed to reach accepted levels of statistical significance after correction for the effects of multiple statistical comparisons, age and total brain size. Physiological right-left asymmetry, reported for temporal and frontal lobe volumes, was present in control, schizophrenic and delusional disorder subjects but delusional disorder patients had a significantly greater degree of temporal lobe asymmetry. The results add to the evidence for heterogeneity among late-onset psychoses and emphasize the subtle nature of any structural brain abnormalities in these patients.

Aged↗
PubMed1992

Immunoreactive parvalbumin concentrations in parahippocampal gyrus decrease in patients with Alzheimer's disease.

By using a sensitive enzyme immunoassay system for rat parvalbumin, we determined parvalbumin contents in the 4 cerebrocortical regions (superior frontal gyrus of frontal lobe, parahippocampal gyrus of temporal lobe, superior parietal lobule of parietal lobe, and calcarine area of occipital lobe) of patients with Alzheimer's disease and age-matched controls. Among the 4 regions, concentrations of parvalbumin were the highest in calcarine area (68.6 +/- 6.7 ng/mg protein, rat parvalbumin equivalents, mean +/- SE) and the lowest in the parahippocampal gyrus (11.0 +/- 1.7 ng/mg protein) in the controls. A similar regional difference of the concentration was observed also in the patients with Alzheimer's disease. When compared with the controls, however, concentrations of parvalbumin in parahippocampal gyrus of patients with Alzheimer's disease (4.0 +/- 0.9 ng/mg protein) were significantly low (P less than 0.01), showing less than a half of the control values. In contrast, the concentrations in the 3 other regions showed little difference between Alzheimer's disease and the controls.

Alzheimer Disease↗
PubMed2002

Volumetric stereotaxy and the supratentorial occipitosubtemporal approach in the resection of posterior hippocampus and parahippocampal gyrus lesions.

OBJECTIVE: Resection of intracranial tumors in the posterior hippocampus and the parahippocampal gyrus can be associated with significant morbidity because of the parenchymal resection and the cortical retraction often required in gaining access to this infrequently explored region. With the use of image guidance, the occipitosubtemporal (OST) approach requires neither lateral cortical resection nor the placement of brain retractors to gain surgical access to the posterior hippocampus and the parahippocampal gyrus, and this approach is associated with a high rate of gross total tumor resection. METHODS: The computer-assisted volumetric stereotactic OST approach was used to resect 40 posterior hippocampus and parahippocampal gyrus tumors in 34 consecutive patients during an 8-year period. Patient, radiographic, and surgical outcome data were collected retrospectively. RESULTS: The series included operations in 25 men and 15 women, and the patients' average age was 40.3 years (range, 15-69 yr). Twenty-five of the 40 procedures were performed to remove lesions in the dominant hemisphere, and previous craniotomies for resection had been performed in 12 of 40 cases. In 38 of 40 cases, histopathological analysis revealed a glial neoplasm, and 50% of these tumors were high-grade lesions. Preoperatively, 23 patients were neurologically intact before 40 procedures, whereas visual field deficits were noted in 7 patients, mild hemiparesis was documented in 4 patients, and other neurological deficits were present in 9 patients. An excellent outcome (Glasgow Outcome Scale Grade 5) was noted after 38 (95%) of the 40 computer-assisted volumetric stereotactic OST procedures. Permanent postoperative hemiparesis (Glasgow Outcome Scale Grade 4) occurred after one procedure, and a second patient, despite being neurologically unchanged postoperatively and despite having had an optimal tumor resection, died on postoperative Day 33 (Glasgow Outcome Scale Grade 1). Complete resection of the preoperatively defined tumor volume was noted on postoperative gadolinium-enhanced magnetic resonance imaging examinations after 39 (97.5%) of the 40 procedures. The average duration of clinical follow-up was 15.9 months (range, 0.5-67 mo). CONCLUSION: We think that the OST approach is well suited to the resection of tumors in the posterior hippocampus and the parahippocampal gyrus. By allowing the neurosurgeon to avoid unnecessary brain resection and retraction, this approach reduces the risk of injury to important lateral temporal and occipital lobe cortex and tracts. In addition, the resection of a posterior hippocampus or parahippocampal gyrus mass with the OST approach relieves temporal horn entrapment. Computer-assisted volumetric stereotaxy helps the neurosurgeon to maintain precise spatial and anatomic orientation and accurately delineates the margin between the tumor and the surrounding neural tissue.

Adolescent↗
PubMed2004

The parahippocampal gyrus in the baboon: anatomical, cytoarchitectonic and magnetic resonance imaging (MRI) studies.

The parahippocampal gyrus, located at the medial temporal lobe, is a key structure in declarative memory processing. We have analyzed the general organization of the parahippocampal gyrus in the baboon, a nonhuman primate species relatively close to human. This region is rostrocaudally made up of the temporopolar, perirhinal, entorhinal (divided into seven subfields) and posterior parahippocampal (areas TH and TF) cortices. The basic analysis has been performed in three brains, serially sectioned and stained with thionin, myelin stain, acetylcholinesterase and parvalbumin, to determine cytoarchitectonic boundaries. Borders of all subfields were charted onto camera lucida drawings, and two-dimensional maps of the surface and topography of the parahippocampal gyrus were made. Finally, the limits of each parahippocampal area were then transposed on corresponding MR images (commonly used for in vivo PET or functional MRI activation studies) of two animals for precise identification. The general cytoarchitectonic features of the baboon parahippocampal gyrus are similar to macaques, but the size of temporopolar cortex and the laminar organization of perirhinal and posterior parahippocampal cortices resemble humans more than macaque species. In conclusion, the size and structure of the baboon parahippocampal cortex makes this species very appropriate for experimental studies on memory function.

Animals↗
PubMed2004

Noninvasive in vivo demonstration of the connections of the human parahippocampal gyrus.

MR tractography techniques provide a method for noninvasively studying white matter pathways in vivo. In this study we have used diffusion tensor imaging (DTI) and the fast marching tractography (FMT) algorithm to plot the structural connectivity of the human parahippocampal gyrus (PHG) in 10 healthy subjects, using seed points selected in the anterior parahippocampal gyrus. Our results demonstrate connectivity between the parahippocampal gyrus and the anterior temporal lobe, orbitofrontal areas, posterior temporal lobe and extrastriate occipital lobe via the lingual and fusiform gyri. We also demonstrate for the first time noninvasively direct connectivity between the parahippocampal gyrus and the hippocampus itself. These results agree with previous histological tract-tracing studies in animals. The connections demonstrated between neocortical areas and the hippocampus via the parahippocampal gyrus may provide the structural basis for theoretical models of memory and higher visual processing.

Adult↗
PubMed2000

The parahippocampal gyrus in Alzheimer's disease. Clinical and preclinical neuroanatomical correlates.

The human parahippocampal gyrus forms a large part of the limbic lobe along the ventromedial part of the temporal cortical mantle. It is a variable and complicated cortex in terms of structure, and the latter is aggravated further by interfaces with the anterior insula anteriorly and the cingulate gyrus and occipital lobe posteriorly. Additional complications relate to its lateral border with the temporal cortex and especially the sulcal configurations that define this junction. The rhinal sulcus, which separates parahippocampal and temporal cortices in other species, including the anthropoid apes, is either lacking or rudimentary in the human brain. Thus, defining this junction requires cytoarchitectural examination and precludes the use of mere inspection of sulcal existing patterns. The cortical areas that form the parahippocampal gyrus are vulnerable to pathological changes in Alzheimer's disease (AD), and its entorhinal and perirhinal subdivisions are both the most heavily damaged cortical areas and the focus for disease onset. The neurons that acquire neurofibrillary tangles (NFTs) occupy the junction of the isocortical mantle with the limbic cortical mantle, but share, or partially share, a vulnerability phenotype with large neurons in both domains. The differential expression of this phenotype across time creates the false impression of NFT spread in cross-sectional comparisons of AD brains. The questions of what this phenotype is and why it is expressed first in the perirhinal and entorhinal cortices of the parahippocampal gyrus are the central molecular biological/neuroanatomical questions in understanding the etiology of AD.

Alzheimer Disease↗
PubMed2004

Impaired associative memory in temporal lobe epilepsy subjects after lesions of hippocampus, parahippocampal gyrus, and amygdala.

There has been growing interest in the differential role of medial temporal lobe structures in learning and memory. The goal of the present study was to clarify how lesions of hippocampus, parahippocampal gyrus, and amygdala interfere with associative learning and memory. Thirty subjects with pharmacoresistant medial temporal lobe epilepsy (TLE) and temporal lobe removal were compared with 30 matched healthy control subjects. A set of neuropsychological test measures and an associative learning task requiring the learning and recall of objects and faces were administered. The lesions of hippocampus, parahippocampal gyrus, amygdala, and fusiform gyrus of TLE subjects were determined by three-dimensional magnetic resonance imaging (3-D MRI) volumetric assessment. The results indicate that TLE subjects with combined large hippocampal lesions, large parahippocampal gyrus (i.e., perirhinal/entorhinal) lesions, and large amygdala lesions learned and recalled the associative task significantly worse than control subjects or subjects with small lesions of the hippocampus, parahippocampal gyrus, and amygdala. Regression analysis revealed that larger lesions of the parahippocampal gyrus (i.e., perirhinal/entorhinal cortices) were significantly related to increasing deficits on the task, and that hippocampal and amygdala lesion size did not significantly improve the prediction. Our results suggest that perirhinal and entorhinal cortices may contribute predominantly to the associative learning and recall of objects and faces.

Adult↗
PubMed1988

Acetylcholinesterase fiber staining in the human hippocampus and parahippocampal gyrus.

The AChE fiber distribution within the human hippocampus and parahippocampal gyrus was studied in order to provide normative data for the examination of cholinergic fiberarchitecture in human pathology and to clarify the cytoarchitectonic organization of these structures. A modification of the Koelle method was used to stain temporal lobe serial sections from 6 neurologically normal human brains collected at autopsy. The hippocampal formation contains some of the densest staining of any cortical area. Regions with the heaviest concentrations of AChE fibers include a thin band along the inner edge of the molecular layer of the dentate gyrus (ml-DG) and parts of the CA2, CA3, and CA4 sectors of Ammon's horn. Staining is of intermediate intensity in the CA1 region. The subiculum (S) is more lightly stained than the CA fields. Staining in the parahippocampal gyrus is generally less dense than in the hippocampal formation. The most conspicuous feature of the human entorhinal cortex (EC) is the AChE-rich fiber patches seen overlapping the stellate cell islands in layer II. An additional band of relatively dense AChE staining is identified in layers IV-V. Prominent AChE-rich polymorphic neurons are present within the hilum of the dentate gyrus. The CA1/subiculum transition in Nissl preparation is characterized by an oblique interdigitation of CA1 cells. The transition from EC to prorhinal cortex occurs along the medial bank of the rhinal sulcus and is characterized by a band of AChE staining, which slopes obliquely away from layer II until it joins an intermediate pyramidal cell layer. Some comparisons with AChE staining in the monkey were made. The monkey has a similar pattern except in DG, where the intensely AChE staining band along the inner ml-DG is thicker and much more prominent. In comparison to the human, the monkey has more conspicuous AChE staining in the parasubicular region.

Acetylcholinesterase↗
PubMed1997

Excitatory amino acids and monoamines in parahippocampal gyrus and frontal cortical pole of adults with Down syndrome.

Aspartate (ASP), glutamate (GLU), noradrenaline (NA), dopamine (DA) and its acidic metabolites DOPAC and HVA, serotonin (5-HT) and its metabolite 5-HIAA were simultaneously investigated in post-mortem tissue samples from right parahippocampal gyrus (temporal cortex) and frontal cortical pole (frontal cortex) of adults with Down syndrome (DS), and of neurologically healthy controls by use of high performance liquid chromatography (HPLC). In parahippocampal gyrus, ASP, GLU, NA, DOPAC and 5-HT levels were significantly decreased in patients with DS, compared to levels found in control subjects (approximately 50%). No significant changes were observed in frontal pole. ASP and GLU levels were significantly lower in parahippocampal gyrus than in frontal pole of DS, a regional distribution that could not be observed in control subjects. In conclusion, the results of this study suggest that the temporal cortex would be more affected than the frontal cortex in adult patients with DS, a finding in line with reports showing a marked hypometabolism and extensive cell loss in temporal cortex of DS, and with those showing that parahippocampal gyrus abnormality may correlate with the extent of mental retardation affecting this type of patients.

Biogenic Monoamines↗
PubMed1993

[An autopsy case with recent memory disturbance, characterized by localized atrophy of parahippocampal gyrus, subiculum and amygdala].

We reported an autopsy case with recent memory disturbance, characterized by localized atrophy of parahippocampal gyrus, subiculum and amygdala. This patient initially exhibited recent memory disturbance at the age of 73. She was disoriented to time and place and immediately forgot having had a meal. At the age of 75, she was hospitalized because of progressive forgetfulness and congestive heart failure. One year later, she was admitted to our medical center. On admission, she was alert, but showed severe recent memory disturbance and disorientation to time and place. By contrast, she had neither aphasia nor apraxia. No other neurological symptoms were found. Brain CT showed localized atrophy of the medial part of bilateral temporal lobes and brain SPECT (123I-IMP) revealed a decrease of cerebral blood flow in the same regions. We considered her as early stage of Alzheimer type dementia (ATD) clinically. She died of pneumonia and DIC at the age of 78. Her illness lasted about 5 years. General autopsy showed prolapse of mitral valves, bronchopneumonia and DIC. The brain weighed 1,150 gm. Coronal sections of the brain revealed locarized atrophy of bilateral mediobasal part of the temporal lobes including the rostral parahippocampal gyrus, subiculum and amygdala. There were severe neuronal loss with astrogliosis and a few neurofibrillary tangles (NFT) in the rostral para-hippocampus, CA1 of the hippocampal formation, prosubiculum and amygdala. There were neither senile plaques (SP) nor NFT in the cerebral neocortex. This case lacked neocortical SP and NFT and showed bilateral localized atrophy of rostral parahippocampal gyrus, CA1, subiculum and related structure of the ventromedial temporal lobe with severe neuronal loss and astrogliosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1998

Memory impairments associated with hippocampal versus parahippocampal-gyrus atrophy: an MR volumetry study in Alzheimer's disease.

Delayed memory impairments and medial temporal-lobe atrophy are considered to be cardinal features of Alzheimer's disease (AD). The goal of the present magnetic resonance (MR) volumetry study was to investigate the relationship between both features. We determined MR-derived estimates of hippocampal and parahippocampal volume in a sample of 27 AD patients and in a group of 26 healthy control subjects (NCs) of comparable age and education. We examined the performance of the two groups on immediate and delayed recall trials of an auditory-verbal list-learning task (CVLT), a visual non-verbal memory task (Visual Reproduction of the WMS-R), and a screening procedure that provides an estimate of overall cognitive functioning (DRS). Volumes of the hippocampus and the parahippocampal gyrus were significantly smaller in AD patients than in NCs. AD patients were impaired in their overall level of cognitive functioning and showed memory deficits under immediate and delayed recall conditions. The association between medial temporal-lobe atrophy and cognitive impairments in AD was found to be highly specific: Hippocampal volume correlated positively with delayed but not immediate recall of the verbal auditory list learning task. In contrast, parahippocampal gyrus volume, specifically in the right hemisphere, was positively related to delayed but not immediate recall of the non-verbal visual memory task. In NCs, there was a trend towards a negative association between hippocampal volumes and delayed verbal recall. Our results suggest that hippocampal and parahippocampal gyrus atrophy in AD are related to distinct aspects of the patients' memory impairments. Our findings have implications for current discussions regarding contributions of the hippocampus and the parahippocampal gyrus to memory in the intact human brain.

Aged↗
PubMed2000

Anomalous asymmetry of fusiform and parahippocampal gyrus gray matter in schizophrenia: A postmortem study.

OBJECTIVE: Anomalies of structure and asymmetry of the parahippocampal gyrus (origin of the perforant path input to the hippocampal formation in the medial temporal lobe) have been shown in some postmortem studies of schizophrenia, but previous studies have not included the fusiform gyrus (which may have a role in facial recognition and naming), adjacent to the parahippocampal gyrus on the ventral occipitotemporal surface. METHOD: The volumes of gray matter in the left and right parahippocampal and fusiform gyri were assessed with a stereological point-counting technique in the temporal lobes from formalin-fixed brains of 27 comparison subjects and 31 patients with schizophrenia. Age was a covariate and gender was a factor in the analysis. RESULTS: In relation to the comparison subjects, the schizophrenic patients (both sexes) had lower volumes of both the parahippocampal and fusiform gyri on the left side. For both structures a left-greater-than-right volume asymmetry was present in the comparison subjects, but this asymmetry was reversed in the parahippocampal and fusiform gyri of the schizophrenic patients. A sex difference was present with respect to age at onset-degree of anomaly of asymmetry for both gyri increased with age at onset in men but not in women. CONCLUSIONS: The findings add substance to the view that the sex-related dimension of symmetry/asymmetry is integral to the disease process in schizophrenia and draw attention to the fusiform gyrus as a structure of particular interest in relation to disturbances of identification and naming in psychosis.

Adult↗
PubMed2002

Decreased phorbol ester binding in the parahippocampal gyrus from subjects with schizophrenia is not associated with changes in protein kinase C.

Combining in situ radioligand binding with autoradiography, we previously identified a reduction of [(3)H]phorbol 12,13-dibutyrate binding in the parahippocampal gyrus from schizophrenic subjects. To determine whether these changes were due to decreases in the level of protein kinase C, we measured [(3)H]phorbol 12,13-dibutyrate binding, levels of the protein kinase C isoforms alpha, beta, delta, epsilon, gamma, eta and theta, as well as protein kinase C activity in crude particulate membranes from parahippocampal gyri of 15 schizophrenic and 15 control subjects. There was a significant decrease in the density (mean +/- SEM: 6.56 +/- 0.73 pmol mg(-1) vs 9.68 +/- 1.22 pmol mg(-1); P < 0.05) and affinity (mean K(D) +/- SEM: 4.64 +/- 0.34 nM vs 2.95 +/- 0.35 nM; P < 0.005) of [(3)H]phorbol 12,13-dibutyrate binding in homogenates from schizophrenic subjects. There were no significant changes in levels of the protein kinase C isoforms which are known to bind phorbol esters or in the activity of protein kinase C in membranes from schizophrenic subjects. These results suggest that there are changes in molecules capable of binding [(3)H]phorbol 12,13-dibutyrate, other than protein kinase C, in the parahippocampal gyrus from subjects with schizophrenia.

Adult↗
PubMed2003

Analysis of parahippocampal gyrus in 115 patients with hippocampal sclerosis.

PURPOSE: Analysis of the parahippocampal gyrus (PHG) involvement in 115 patients with hippocampal sclerosis (HS) by MR imaging. The simultaneous occurrence of ipsilateral fornix (F) and mamillary body (MB) volume loss was checked also. These findings were correlated with the side of hippocampal involvement, the sex, patient s age, and the symptoms onset. METHOD: The MR images of 115 patients with HS were studied retrospectively. All the examinations were performed on 1.5 T units (SIGNA, GE, Milwaukee, WI) and included high resolution coronal T2-weighted images (3 mm thickness, 0.6 mm gap). RESULTS: The patient's age ranged between 3.5 and 80 years (mean 34.1); 62 (53.9%) were female and 53 (46.1%) were male. There were HS on the left side in 53 (46.0%), on the right side in 51 (44.3%), and bilateral in 11 (9.7%). In 43 (37.3%) cases there were ipsilateral PHG volume loss and signal hyper intensity on T2-weighted imaging. In 29 (25.2%) cases there were ipsilateral fornix volume loss and in 10 (34.5%) of this there were also ipsilateral MB changes. In abnormal PHG, 23 (53.4%) were on the left side, 17 (39.5%) were on the right side, and 3 (7.1%) were bilateral. There were fornix changes in 15 (34.8%) cases and MB volume loss in 5 (11.6%) cases. Pertinent clinical data were obtained in only 18 (41.8%) of the PHG lesion cases and 11 (61.1%) of these patients had epileptic attacks for more than 20 years before the examination. CONCLUSION: PHG involvement must be investigated in patients with HS and we suggest that the term mesial temporal sclerosis should be used only if there are also changes at this anatomical site.

Adolescent↗
PubMed2003

Parcellation of cortical afferents to three distinct sectors in the parahippocampal gyrus of the rhesus monkey: an anatomical and neurophysiological study.

The posterior parahippocampal gyrus (PHG) of the rhesus monkey (Macaca mulatta) is comprised of three distinct cortical areas based on cytoarchitecture, connectivity, and neurophysiological response properties. Fluorescent retrograde tracers placed in each PHG area demonstrated unique patterns of cortical afferent input to areas TH, TL, and TF. Area TF receives inputs from the multimodal cortices of the superior temporal sulcus including areas PGa, TPO, and MST, from the visuospatial parietal area PG-Opt, and from visual areas V3A and dorsal V4. Area TL receives afferents from the inferotemporal region including visual areas TE1 and TE2 as well as from areas TEa, IPa, and FST in the lower bank and depth of the superior temporal sulcus. In contrast, the input to area TH is from the rostral part of superior temporal gyrus, including the auditory association areas TS1-3, and from the middle sector of area TPO in the superior temporal sulcus. Frontal and cingulate areas also project to the PHG in largely differential patterns. To further investigate this a correlative electrophysiological study of the three PHG areas resulted in a confirmation of these differential cortical inputs such that visually responsive neurons were found in areas TF and TL, auditory responsive neurons or bimodal auditory/visual-responsive neurons in area TH, and somatosensory-responsive neurons at the TF/TL border. Since each PHG area also receives differential hippocampal input, these data suggest that the processing of unimodal or multimodal information may be related to memory processing functions that are largely segregated within areas TH, TL, and TF.

Afferent Pathways↗
PubMed1990

Increased forskolin binding in the left parahippocampal gyrus and CA1 region in post mortem schizophrenic brain determined by quantitative autoradiography.

Using quantitative autoradiography of [3H]forskolin we have visualized the activated states of adenylate cyclase in the hippocampal formation bilaterally in sections from schizophrenic brain and age-matched controls. There is a generalized increase in binding in schizophrenic hippocampi, particularly in the CA1 region and parahippocampal gyrus. The effect is particularly marked in the left parahippocampal gyrus. These findings add some support to the notion of schizophrenia as a medial temporal lobe disorder and suggest novel substrates as therapeutic targets in schizophrenia.

Adenylyl Cyclases↗