Structural and functional neuroimaging correlates of depression in temporal lobe epilepsy

2007 ◽  
Vol 10 (2) ◽  
pp. 242-249 ◽  
Author(s):  
Elizabeth J. Richardson ◽  
H. Randall Griffith ◽  
Roy C. Martin ◽  
A. LeBron Paige ◽  
Christopher C. Stewart ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Functional Neuroimaging

scholarly journals Semantic Processing Impairment in Patients with Temporal Lobe Epilepsy

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Amanda G. Jaimes-Bautista ◽  
Mario Rodríguez-Camacho ◽  
Iris E. Martínez-Juárez ◽  
Yaneth Rodríguez-Agudelo
Keyword(s):  
Episodic Memory ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Semantic Processing ◽  
Functional Neuroimaging ◽  
Declarative Memory ◽  
Semantic Networks ◽  
N400 Effect ◽  
Functional Reorganization ◽  
Electrophysiological Studies

The impairment in episodic memory system is the best-known cognitive deficit in patients with temporal lobe epilepsy (TLE). Recent studies have shown evidence of semantic disorders, but they have been less studied than episodic memory. The semantic dysfunction in TLE has various cognitive manifestations, such as the presence of language disorders characterized by defects in naming, verbal fluency, or remote semantic information retrieval, which affects the ability of patients to interact with their surroundings. This paper is a review of recent research about the consequences of TLE on semantic processing, considering neuropsychological, electrophysiological, and neuroimaging findings, as well as the functional role of the hippocampus in semantic processing. The evidence from these studies shows disturbance of semantic memory in patients with TLE and supports the theory of declarative memory of the hippocampus. Functional neuroimaging studies show an inefficient compensatory functional reorganization of semantic networks and electrophysiological studies show a lack of N400 effect that could indicate that the deficit in semantic processing in patients with TLE could be due to a failure in the mechanisms of automatic access to lexicon.

scholarly journals Neuropsychology in Temporal Lobe Epilepsy: Influences from Cognitive Neuroscience and Functional Neuroimaging

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Mary Pat McAndrews ◽  
Melanie Cohn
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Functional Imaging ◽  
Cognitive Neuroscience ◽  
Surgical Planning ◽  
Current Practice ◽  
Functional Neuroimaging ◽  
Mapping Function ◽  
Current Assessment ◽  
Assessment Strategies

Neuropsychologists assist in diagnosis (i.e., localization of dysfunction) and in prediction (i.e., how cognition may change following surgery) in individuals being considered for temporal lobe surgery. The current practice includes behavioural testing as well as mapping function via stimulation, inactivation, and (more recently) functional imaging. These methods have been providing valuable information in surgical planning for 60 years. Here, we discuss current assessment strategies and highlight how they are evolving, particularly with respect to integrating recent advances in cognitive neuroscience.

Machine learning for detecting mesial temporal lobe epilepsy by structural and functional neuroimaging

2020 ◽  
Vol 14 (5) ◽  
pp. 630-641
Author(s):  
Baiwan Zhou ◽  
Dongmei An ◽  
Fenglai Xiao ◽  
Running Niu ◽  
Wenbin Li ◽  
...  
Keyword(s):  
Machine Learning ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Functional Neuroimaging ◽  
Mesial Temporal Lobe Epilepsy ◽  
Mesial Temporal Lobe

Functional neuroimaging strategy in temporal lobe epilepsy: A comparative study of18FDG-PET and99mTc-HMPAO-SPECT

1992 ◽  
Vol 31 (6) ◽  
pp. 650-656 ◽  
Author(s):  
Philippe Ryvlin ◽  
Bernard Philippon ◽  
Luc Cinotti ◽  
Jean C. Froment ◽  
Didier Le Bars ◽  
...  
Keyword(s):  
Comparative Study ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Functional Neuroimaging ◽  
Hmpao Spect

Treatment of Proper Name Retrieval Deficits in an Individual With Temporal Lobe Epilepsy

2013 ◽  
Vol 22 (2) ◽  
Author(s):  
Irene Minkina ◽  
Jeffrey G. Ojemann ◽  
Thomas J. Grabowski ◽  
JoAnn P. Silkes ◽  
Vaishali Phatak ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Functional Neuroimaging ◽  
Treatment Completion ◽  
Word Retrieval ◽  
Single Subject ◽  
Left Temporal Lobe ◽  
Clinical Onset ◽  
Proper Name ◽  
Name Retrieval

Purpose Studies investigating language deficits in individuals with left temporal–lobe epilepsy have consistently demonstrated impairments in proper name retrieval. The aim of this Phase I rehabilitation study was to investigate the effects of a linguistically distributed word retrieval treatment on proper name retrieval in an individual with left temporal–lobe epilepsy. Method A 61-year old right-handed male with left temporal–lobe epilepsy (clinical onset at the age of 50) and a deficit in proper name retrieval participated in this study. A single-subject, repeated-probe ABAA design with testing before, immediately after, and 3 months after treatment completion was employed. Proper name retrieval treatment was administered 2 hr per day for 5 days. Results Results demonstrated improved naming on trained items and maintenance of trained items 3 months after treatment completion. Conclusion Treatment, which took advantage of the individual's undamaged linguistic networks, promoted the reorganization of networks supporting proper naming, leading to improved proper name retrieval. Further research replicating these findings in individuals with varying degrees of proper name retrieval impairment is warranted. Additionally, the mechanism behind the observed improvements in proper name retrieval needs to be investigated further using functional neuroimaging.

scholarly journals Diminished default mode network recruitment of the hippocampus and parahippocampus in temporal lobe epilepsy

2013 ◽  
Vol 119 (2) ◽  
pp. 288-300 ◽  
Author(s):  
G. Andrew James ◽  
Shanti Prakash Tripathi ◽  
Jeffrey G. Ojemann ◽  
Robert E. Gross ◽  
Daniel L. Drane
Keyword(s):  
Functional Connectivity ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Default Mode Network ◽  
Resting State ◽  
Functional Neuroimaging ◽  
Parahippocampal Gyrus ◽  
Epileptogenic Focus ◽  
Data Set ◽  
Default Mode

Object Functional neuroimaging has shown that the brain organizes into several independent networks of spontaneously coactivated regions during wakeful rest (resting state). Previous research has suggested that 1 such network, the default mode network (DMN), shows diminished recruitment of the hippocampus with temporal lobe epilepsy (TLE). This work seeks to elucidate how hippocampal recruitment into the DMN varies by hemisphere of epileptogenic focus. Methods The authors addressed this issue using functional MRI to assess resting-state DMN connectivity in 38 participants (23 control participants, 7 patients with TLE and left-sided epileptogenic foci, and 8 patients with TLE and right-sided foci). Independent component analysis was conducted to identify resting-state brain networks from control participants' data. The DMN was identified and deconstructed into its individual regions of interest (ROIs). The functional connectivity of these ROIs was analyzed both by hemisphere (left vs right) and by laterality to the epileptogenic focus (ipsilateral vs contralateral). Results This attempt to replicate previously published methods with this data set showed that patients with left-sided TLE had reduced connectivity between the posterior cingulate (PCC) and both the left (p = 0.012) and right (p < 0.002) hippocampus, while patients with right-sided TLE showed reduced connectivity between the PCC and right hippocampus (p < 0.004). After recoding ROIs by laterality, significantly diminished functional connectivity was observed between the PCC and hippocampus of both hemispheres (ipsilateral hippocampus, p < 0.001; contralateral hippocampus, p = 0.017) in patients with TLE compared with control participants. Regression analyses showed the reduced DMN recruitment of the ipsilateral hippocampus and parahippocampal gyrus (PHG) to be independent of clinical variables including hippocampal sclerosis, seizure frequency, and duration of illness. The graph theory metric of strength (or mean absolute correlation) showed significantly reduced connectivity of the ipsilateral hippocampus and ipsilateral PHG in patients with TLE compared with controls (hippocampus: p = 0.028; PHG: p = 0.021, after correction for false discovery rate). Finally, these hemispheric asymmetries in strength were observed in patients with TLE that corresponded to hemisphere of epileptogenic focus; 87% of patients with TLE had weaker ipsilateral hippocampus strength (compared with the contralateral hippocampus), and 80% of patients had weaker ipsilateral PHG strength. Conclusions This study demonstrated that recoding brain regions by the laterality to their epileptogenic focus increases the power of statistical approaches for finding interhemispheric differences in brain function. Using this approach, the authors showed TLE to selectively diminish connectivity of the hippocampus and parahippocampus in the hemisphere of the epileptogenic focus. This approach may prove to be a useful method for determining the seizure onset zone with TLE, and could be broadly applied to other neurological disorders with a lateralized onset.

Theory of mind and social competence in children and adolescents with temporal lobe epilepsy.

2019 ◽  
Vol 33 (7) ◽  
pp. 986-995 ◽  
Author(s):  
Elizabeth Stewart ◽  
Cathy Catroppa ◽  
Linda Gonzalez ◽  
Deepak Gill ◽  
Richard Webster ◽  
...  
Keyword(s):  
Theory Of Mind ◽  
Social Competence ◽  
Temporal Lobe Epilepsy ◽  
Children And Adolescents ◽  
Temporal Lobe
Sign in / Sign up

Export Citation Format

Share Document