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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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Focal seizure with temporal lobe onset and generalization

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Dr. Rishabh Pathak


Focal seizures with temporal lobe onset that generalize involve seizure activity that begins in the temporal lobe and subsequently spreads to involve both hemispheres of the brain.

1.      Ictal Patterns:

o    The EEG during focal seizures with temporal lobe onset typically shows an initial focal pattern that may evolve into generalized rhythmic activity. This can include an increase in amplitude and the presence of high-frequency rhythms at the temporal electrodes, particularly on the side of the seizure onset.

2.     Clinical Manifestations:

o    Patients may experience a range of symptoms, including alterations in consciousness, memory disturbances, and motor manifestations such as tonic posturing or clonic movements. The initial focal onset may present with specific symptoms related to the temporal lobe, such as auditory hallucinations or emotional changes, before progressing to generalized convulsions.

3.     EEG Characteristics:

o    The ictal pattern often shows an increase in amplitude bilaterally with the onset of the seizure, but the right temporal region may exhibit greater rhythmicity. The EEG may also demonstrate muscle artifact as the seizure progresses, which can obscure the underlying cerebral activity.

4.    Associated Conditions:

o    Focal seizures with temporal lobe onset and generalization can be associated with various conditions, including temporal lobe epilepsy, structural lesions such as hippocampal sclerosis, or tumors. These seizures may also occur in the context of idiopathic epilepsy syndromes.

5.     Diagnosis and Management:

o    Diagnosis typically involves a combination of clinical history, EEG monitoring, and neuroimaging (such as MRI) to identify any underlying structural abnormalities. Management may include antiepileptic medications, and in cases where seizures are refractory to medical treatment, surgical options such as temporal lobectomy may be considered.

6.    Prognosis:

o    The prognosis for patients with focal seizures of temporal lobe onset that generalize can vary based on the underlying cause and the response to treatment. Some patients may achieve good seizure control with medication, while others may require surgical intervention for better outcomes.

In summary, focal seizures with temporal lobe onset and generalization are characterized by specific ictal patterns and a range of clinical manifestations that reflect their origin in the temporal lobe. Understanding these seizures is essential for accurate diagnosis and effective management, particularly in the context of temporal lobe epilepsy.

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