Asymmetry of Neuronal Activity During Extracellular Microelectrode Recording from Left and Right Human Temporal Lobe Neocortex During Rhyming and Line-Matching

2000 ◽  
Vol 12 (5) ◽  
pp. 803-812 ◽  
Author(s):  
Theodore H. Schwartz ◽  
Michael M. Haglund ◽  
Ettore Lettich ◽  
George A. Ojemann
Keyword(s):  
Temporal Lobe ◽  
Neuronal Activity ◽  
Right Hemisphere ◽  
Cerebral Dominance ◽  
Firing Frequency ◽  
Hemispheric Lateralization ◽  
Temporal Lobectomy ◽  
Complex Partial Seizures ◽  
Match To Sample ◽  
The Right

Recordings of neuronal activity in humans have identified few correlates of the known hemispheric asymmetries of functional lateralization. Here, we examine single-unit activity recorded from both hemispheres during two delayed match-to-sample tasks that show strong hemispheric lateralization based on lesion effects; a line-matching (LM) task related to the right hemisphere, and a rhyming (RHY) task related to the left. Nineteen neuronal populations were recorded with extracellular microelectrodes from the left temporal neocortex of 11 awake patients, and 18 from the right in 9 patients during anterior temporal lobectomy for complex partial seizures under local anesthesia. All subjects were left hemisphere dominant for language. Twelve (32%) populations exhibited statistically significant changes in activity at p < .05. Although changes in firing frequency were recorded from both hemispheres during both tasks, the RHY task elicited changes in activity several hundred milliseconds earlier on the left side than on the right. The LM task, on the other hand, induced changes earlier on the right side than on the left. Both hemispheres contained units active during verbal responses regardless of which behavior elicited the response. Our results indicate that cerebral dominance is reflected in earlier neuronal activity in the anterior temporal lobe during tasks lateralized to that hemisphere.

scholarly journals Cerebral Hemispheric Lateralization Associated with Hippocampal Sclerosis May Affect Interictal Cardiovascular Autonomic Functions in Temporal Lobe Epilepsy

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Rokia Ghchime ◽  
Halima Benjelloun ◽  
Hajar Kiai ◽  
Halima Belaidi ◽  
Fatiha Lahjouji ◽  
...  
Keyword(s):  
Heart Rate ◽  
Temporal Lobe Epilepsy ◽  
Temporal Lobe ◽  
Cerebral Hemisphere ◽  
Autonomic Function ◽  
Hippocampal Sclerosis ◽  
Hemispheric Lateralization ◽  
Unexpected Death ◽  
Complex Partial Seizures ◽  
The Right

It is well established that the temporal lobe epilepsy (TLE) is linked to the autonomic nervous system dysfunctions. Seizures alter the function of different systems such as the respiratory, cardiovascular, gastrointestinal, and urogenital systems. The aim of this work was to evaluate the possible factors which may be involved in interictal cardiovascular autonomic function in temporal lobe epilepsy with complex partial seizures, and with particular attention to hippocampal sclerosis. The study was conducted in 30 patients with intractable temporal lobe epilepsy (19 with left hippocampal sclerosis, 11 with right hippocampal sclerosis). All subjects underwent four tests of cardiac autonomic function: heart rate changes in response to deep breathing, heart rate, and blood pressure variations throughout resting activity and during hand grip, mental stress, and orthostatic tests. Our results show that the right cerebral hemisphere predominantly modulates sympathetic activity, while the left cerebral hemisphere mainly modulates parasympathetic activity, which mediated tachycardia and excessive bradycardia counterregulation, both of which might be involved as a mechanism of sudden unexpected death in epilepsy patients (SUDEP).

A Double Dissociation in the Affective Modulation of Startle in Humans: Effects of Unilateral Temporal Lobectomy

2001 ◽  
Vol 13 (6) ◽  
pp. 721-729 ◽  
Author(s):  
E. Sumie Funayama ◽  
Christian Grillon ◽  
Michael Davis ◽  
Elizabeth A. Phelps
Keyword(s):  
Temporal Lobe ◽  
Visual Information ◽  
Medial Temporal Lobe ◽  
Emotional Processing ◽  
Right Hemisphere ◽  
Temporal Lobectomy ◽  
Opposite Pattern ◽  
Double Dissociation ◽  
Control Subjects ◽  
The Right

In the present study we report a double dissociation between right and left medial temporal lobe damage in the modulation of fear responses to different types of stimuli. We found that right unilateral temporal lobectomy (RTL) patients, in contrast to control subjects and left temporal lobectomy (LTL) patients, failed to show potentiated startle while viewing negative pictures. However, the opposite pattern of impairment was observed during a stimulus that patients had been told signaled the possibility of shock. Control subjects and RTL patients showed potentiated startle while LTL patients failed to show potentiated startle. We hypothesize that the right medial temporal lobe modulates fear responses while viewing emotional pictures, which involves exposure to (emotional) visual information and is consistent with the emotional processing traditionally ascribed to the right hemisphere. In contrast, the left medial temporal lobe modulates fear responses when those responses are the result of a linguistic/cognitive representation acquired through language, which, like other verbally mediated material, generally involves the left hemisphere. Additional evidence from case studies suggests that, within the medial temporal lobe, the amygdala is responsible for this modulation.

scholarly journals Transient Hemifacial Sensory Loss with Xerophthalmia following Temporal Lobectomy

2000 ◽  
Vol 27 (3) ◽  
pp. 251-253 ◽  
Author(s):  
Ajith J. Thomas ◽  
Kost Elisevich ◽  
Brien Smith
Keyword(s):  
Temporal Lobe ◽  
Clinical Presentation ◽  
Nasal Congestion ◽  
Temporal Lobectomy ◽  
Sensory Loss ◽  
Partial Seizures ◽  
Complex Partial Seizures ◽  
Cavernous Malformations ◽  
Greater Superficial Petrosal Nerve ◽  
The Right

Objective and importance:The occurrence of a unilateral sensory loss in the second trigeminal distribution and the inability to tear following an ipsilateral temporal lobectomy has not been noted despite a number of reports of cranial nerve compromise under similar situations.Clinical presentation:A 48-year-old woman experienced complex partial seizures over three years attributable to the presence of cavernous malformations of the right temporal lobe.Intervention:An anterior temporal extrahippocampal resection was performed. The surgery was marked by the need for electrocoagulation of the dural base of the temporal lobe where numerous bleeding points were encountered. Postoperatively, the patient experienced an ipsilateral maxillary division sensory loss, absence of tearing, and diminished nasal congestion for an eight-month period until resolution.Conclusion:Injury of the fibers of the maxillary division of the trigeminal nerve and the adjacent greater superficial petrosal nerve appears to be the cause. No prior account of such an occurrence has been published.

Fentanyl-induced electrocorticographic seizures in patients with complex partial epilepsy

1992 ◽  
Vol 77 (2) ◽  
pp. 201-208 ◽  
Author(s):  
René Tempelhoff ◽  
Paul A. Modica ◽  
Kerry L. Bernardo ◽  
Isaac Edwards
Keyword(s):  
Temporal Lobe ◽  
Seizure Activity ◽  
Epileptiform Activity ◽  
Temporal Lobectomy ◽  
Electrode Arrays ◽  
Complex Partial Seizures ◽  
Content Type ◽  
Temporal Lobe Seizures ◽  
Eeg Recordings ◽  
The Right

✓ Although electrical seizure activity in response to opioids such as fentanyl has been well described in animals, scalp electroencephalographic (EEG) recordings have failed to demonstrate epileptiform activity following narcotic administration in humans. The purpose of this study was to determine whether fentanyl is capable of evoking electrical seizure activity in patients with complex partial (temporal lobe) seizures. Nine patients were studied in whom recording electrode arrays had been placed in the bitemporal epidural space several days earlier to determine which temporal lobe gave rise to their seizures. The symptomatic temporal lobe was localized by correlating clinical and electrical seizure activity obtained during continuous simultaneous videotape and epidural EEG monitoring. In each patient, clinical seizures and electrical seizure activity were consistently demonstrated to arise unilaterally from one temporal lobe (four on the right, five on the left). During fentanyl induction of anesthesia in preparation for secondary craniotomy for anterior temporal lobectomy, eight of the nine patients exhibited electrical seizure activity at fentanyl doses ranging from 17.7 to 35.71 µg · kg−1 (mean 25.75 µg · kg−1). More importantly, four of these eight seizures occurred initially in the “healthy” temporal lobe contralateral to the surgically resected lobe from which the clinical seizures had been shown to arise. These findings indicate that, in patients with complex partial seizures, moderate doses of fentanyl can evoke electrical seizure activity. The results of this study could have important implications for neurosurgical centers where electrocorticography is used during surgery for the purpose of determining the extent of the resection.

scholarly journals Localization of Syntactic and Semantic Brain Responses using Magnetoencephalography

2007 ◽  
Vol 19 (7) ◽  
pp. 1193-1205 ◽  
Author(s):  
Elisabet Service ◽  
Päivi Helenius ◽  
Sini Maury ◽  
Riitta Salmelin
Keyword(s):  
Temporal Lobe ◽  
Semantic Processing ◽  
Sentence Comprehension ◽  
Right Hemisphere ◽  
Temporal Cortex ◽  
Word Class ◽  
Sentence Reading ◽  
Word Onset ◽  
Semantic Errors ◽  
The Right

Electrophysiological methods have been used to study the temporal sequence of syntactic and semantic processing during sentence comprehension. Two responses associated with syntactic violations are the left anterior negativity (LAN) and the P600. A response to semantic violation is the N400. Although the sources of the N400 response have been identified in the left (and right) temporal lobe, the neural signatures of the LAN and P600 have not been revealed. The present study used magnetoencephalography to localize sources of syntactic and semantic activation in Finnish sentence reading. Participants were presented with sentences that ended in normally inf lected nouns, nouns in an unacceptable case, verbs instead of nouns, or nouns that were correctly inflected but made no sense in the context. Around 400 msec, semantically anomalous last words evoked strong activation in the left superior temporal lobe with significant activation also for word class errors (N400). Weaker activation was seen for the semantic errors in the right hemisphere. Later, 600-800 msec after word onset, the strongest activation was seen to word class and morphosyntactic errors (P600). Activation was significantly weaker to semantically anomalous and correct words. The P600 syntactic activation was localized to bilateral sources in the temporal lobe, posterior to the N400 sources. The results suggest that the same general region of the superior temporal cortex gives rise to both LAN and N400 with bilateral reactivity to semantic manipulation and a left hemisphere effect to syntactic manipulation. The bilateral P600 response was sensitive to syntactic but not semantic factors.

Extent of Mesiobasal Resection Determines Outcome after Temporal Lobectomy for Intractable Complex Partial Seizures

Neurosurgery ◽  
1991 ◽  
Vol 29 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Mohamed H. Nayel ◽  
Issam A. Awad ◽  
Hans Luders
Keyword(s):  
Temporal Lobe ◽  
Seizure Frequency ◽  
Compartment Model ◽  
Extent Of Resection ◽  
Temporal Lobectomy ◽  
Seizure Outcome ◽  
Partial Seizures ◽  
Complex Partial Seizures ◽  
Lateral Structures

Abstract The extent of resection was assessed in 94 patients who underwent temporal lobectomy for medically intractable complex partial seizures originating from a unilateral seizure focus in the anteromesial temporal lobe. Postoperative magnetic resonance imaging in the coronal plane was used to quantify the extent of resection of lateral and mesiobasal structures according to a 20-compartment model of the temporal lobe. Successful seizure outcome (≥90% reduction in seizure frequency) was accomplished in 83% of the patients (all followed up for more than 1 year; mean duration of follow-up, 25.2 months) and correlated significantly (P&lt;0.05) with the extent of mesiobasal resection, regardless of the extent of resection of lateral structures. Successful seizure outcome was accomplished in 81% of the patients with no structural lesions, and also correlated significantly (P&lt;0.05) with the extent of mesiobasal resection regardless of the extent of lateral resection. A successful seizure outcome was accomplished in 90% of the 21 patients with structural lesions documented by neuroimaging studies. Two patients who underwent extensive lobectomy without resection of the structural lesion had no reduction in seizure frequency postoperatively. We conclude that the most important factor in determining the outcome of temporal lobectomy in patients with unilateral anteromesial temporal lobe epileptogenicity is the extent of resection of structures in the mesiobasal temporal lobe. In patients with structural lesions, lesion resection may be an added contributor to successful seizure outcome. (Neurosurgery 29:55-61, 1991)

Preoperative predictors of anterior temporal language areas

1998 ◽  
Vol 89 (6) ◽  
pp. 962-970 ◽  
Author(s):  
Theodore H. Schwartz ◽  
Orrin Devinsky ◽  
Werner Doyle ◽  
Kenneth Perrine
Keyword(s):  
Temporal Lobe ◽  
Right Hemisphere ◽  
Temporal Lobectomy ◽  
Seizure Onset ◽  
Anterior Temporal Lobe ◽  
Verbal Iq ◽  
Content Type ◽  
Language Areas ◽  
Fine Print

Object. Although it is known that 5 to 10% of patients have language areas anterior to the rolandic cortex, many surgeons still perform standard anterior temporal lobectomies for epilepsy of mesial onset and report minimal long-term dysphasia. The authors examined the importance of language mapping before anterior temporal lobectomy. Methods. The authors mapped naming, reading, and speech arrest in a series of 67 patients via stimulation of long-term implanted subdural grids before resective epilepsy surgery and correlated the presence of language areas in the anterior temporal lobe with preoperative demographic and neuropsychometric data. Naming (p < 0.03) and reading (p < 0.05) errors were more common than speech arrest in patients undergoing surgery in the anterior temporal lobe. In the approximate region of a standard anterior temporal lobectomy, including 2.5 cm of the superior temporal gyrus and 4.5 cm of both the middle and inferior temporal gyrus, the authors identified language areas in 14.5% of patients tested. Between 1.5 and 3.5 cm from the temporal tip, patients who had seizure onset before 6 years of age had more naming (p < 0.02) and reading (p < 0.01) areas than those in whom seizure onset occurred after age 6 years. Patients with a verbal intelligence quotient (IQ) lower than 90 had more naming (p < 0.05) and reading (p < 0.02) areas than those with an IQ higher than 90. Finally, patients who were either left handed or right hemisphere memory dominant had more naming (p < 0.05) and reading (p < 0.02) areas than right-handed patients with bilateral or left hemisphere memory lateralization. Postoperative neuropsychometric testing showed a trend toward a greater decline in naming ability in patients who were least likely to have anterior language areas, that is, those with higher verbal IQ and later seizure onset. Conclusions. Preoperative identification of markers of left hemisphere damage, such as early seizure onset, poor verbal IQ, left handedness, and right hemisphere memory dominance should alert neurosurgeons to the possibility of encountering essential language areas in the anterior temporal lobe (1.5–3.5 cm from the temporal tip). Naming and reading tasks are required to identify these areas. Whether removal of these areas necessarily induces long-term impairment in verbal abilities is unknown; however, in patients with a low verbal IQ and early seizure onset, these areas appear to be less critical for language processing.

Right hemisphere speech perception revealed by amobarbital injection and electrical interference

Neurology ◽  
1998 ◽  
Vol 51 (2) ◽  
pp. 458-464 ◽  
Author(s):  
D. Boatman ◽  
J. Hart ◽  
R. P. Lesser ◽  
N. Honeycutt ◽  
N. B. Anderson ◽  
...  
Keyword(s):  
Speech Perception ◽  
Left Hemisphere ◽  
Temporal Lobe ◽  
Right Hemisphere ◽  
Adult Brain ◽  
Left Posterior ◽  
Left And Right ◽  
Sodium Amobarbital ◽  
The Right ◽  
Electrical Interference

Objective: To investigate the right hemispheric speech perception capabilities of an adult right-handed patient with seizures.Methods: Consecutive, unilateral, intracarotid sodium amobarbital injections and left hemispheric electrical interference mapping were used to determine lateralization and localization of speech perception, measured as syllable discrimination.Results: Syllable discrimination remained intact after left and right intracarotid sodium amobarbital injections. Language otherwise strongly lateralized to the left hemisphere. Despite evidence of bilateral speech perception capabilities, electrical interference testing in the left posterior temporal lobe impaired syllable discrimination.Conclusions: The results suggest a functionally symmetric, parallel system in the adult brain with preferential use of left hemispheric pathways for speech perception.

Standardization of an Arabic-Language Neuropsychological Battery for Epilepsy Surgical Evaluations

2019 ◽  
Vol 25 (7) ◽  
pp. 761-771
Author(s):  
Haya F. Al-Joudi ◽  
Lina Mincari ◽  
Salah Baz ◽  
Michael Nester ◽  
Najla Al-Marzouki ◽  
...  
Keyword(s):  
Temporal Lobe ◽  
Cultural Sensitivity ◽  
Right Hemisphere ◽  
Neuropsychological Test ◽  
Arabic Language ◽  
Test Battery ◽  
Temporal Lobectomy ◽  
Johns Hopkins Hospital ◽  
Neuropsychological Test Battery ◽  
Left And Right

AbstractObjectives: This study provides a standardized Arabic language neuropsychological test battery and tests its ability to distinguish patients with left and right hemisphere epileptic foci who are candidates for surgical resection. Methods: An Arabic language battery of 15 tests was developed based on the neuropsychological test battery used at the Johns Hopkins Hospital for surgical evaluation of patients undergoing temporal lobe resection. With modifications where culturally required, 11 tests were translated to Arabic by the principal investigator and back-translated by two bilingual health professionals; four tests were available in Arabic and added to the battery. The battery was administered to 21 Arabic-speaking patients with left temporal epileptic foci, 21 with right temporal epileptic foci, and 46 neurologically and psychiatrically healthy adults. Results: Nearly all the Arabic test versions were capable of differentiating healthy controls and the temporal lobe epilepsy (TLE) groups. Tests known to distinguish left and right temporal lobectomy candidates, such as wordlist memory and prose recall, were able to do so as accurately as the English versions. Also, a roughly “culturally free” task (the Baltimore Board) and a newly developed version of the Boston Naming Test demonstrated some sensitivity to left temporal lobe involvement. Conclusions: Arabic-language neuropsychological tests for epilepsy surgical evaluations are made available, demonstrate cultural sensitivity and clinical validity, and require further psychometric property and normative research. (JINS, 2019, 25, 761–771)

Unilateral ECT as a Test for Cerebral Dominance, with a Strategy for Treating Left-handers

1971 ◽  
Vol 119 (548) ◽  
pp. 79-83 ◽  
Author(s):  
R. T. C. Pratt ◽  
Elizabeth K. Warrington ◽  
A. M. Halliday
Keyword(s):  
Right Hemisphere ◽  
Cerebral Dominance ◽  
Critical Assessment ◽  
Post Treatment ◽  
Therapeutic Equivalence ◽  
Memory And Learning ◽  
The Right ◽  
Bilateral Treatment

The growing adoption of ECT given unilaterally to the right hemisphere in right-handed patients, in preference to the classical bilateral treatment, is due to its shortening of the duration of post-treatment confusion, to its superiority in preserving memory and learning assessed three months after the start of treatment (Halliday et al., 1968) and to its therapeutic equivalence. (For a critical assessment of published results, see d'Elia, 1970.)

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