System for the prediction, rapid detection, warning, prevention, or control of changes in activity states in the brain of a subject

A method of predicting the occurrence of a seizure in the brain of a subject, said method comprising the steps of:

• (a) receiving into a signal processor input signals indicative of the subject's brain activity;
• (b) analyzing said signals for at least one precursor predictive of the occurrence of a seizure in the subject and
• (c) upon occurrence of said at least one precursor, producing an output in response before the onset of electroencephalographic waves signaling the occurrence of the seizure;
• wherein step (b) includes the step of detecting epileptiform discharges in said signals, each discharge presenting a polarity, determining the sharpness of each of said discharges by determining a parabola of optimal fit for each of said discharges, determining an index of relative sharpness to the sharpness of other discharges by comparing each sharpness to the sharpness of other discharges in a time window, determining whether said index reaches a predetermined level, and determining whether said discharges reaching said predetermined level fit a predetermined pattern, such being predictive of a seizure.

A method of predicting the occurrence of a seizure in the brain of a subject, said method comprising the steps of:

• (a) receiving into a signal processor input signals indicative of the subject's brain activity;
• (b) analyzing said signals for at least one precursor predictive of the occurrence of a seizure in the subject and
• (c) upon occurrence of said at least one precursor, producing an output in response before the onset of electroencephalographic waves signaling the occurrence of the seizure;
• wherein step (b) includes the step of determining said precursor by determining a ratio of current signal energy compared to background energy and determining whether said ratio exceeds a predetermined level, such being predictive of a seizure.

A method of predicting the occurrence of a seizure in the brain of a subject, said method comprising the steps of:

• (a) receiving into a signal processor input signals indicative of the subject's brain activity;
• (b) analyzing said signals for at least one precursor predictive of the occurrence of a seizure in the subject and
• (c) upon occurrence of said at least one precursor, producing an output in response before the onset of electroencephalographic waves signaling the occurrence of the seizure;
• wherein step (b) includes the step of determining said precursor by determining a ratio of median frequency to background median frequency and determining whether said ratio exceeds a predetermined level, such being predictive of a seizure.

A seizure detection, prediction and treatment apparatus for detecting the occurrence of a seizure in the brain of a subject, comprising:

• receiving means for receiving input signals indicative of the subject's brain activity;
• signal processing means coupled with said receiving means to:
• determine ictal components in said input signals by applying to said input signals a first filter configured to extract and enhance ictal components from said input signals,
• measure the ictal activity in a foreground epoch of said input signals by applying an order-statistic filter to said ictal components corresponding to said epoch to produce a foreground measure of ictal activity, and
• determine whether said foreground measure exceeds a predetermined level, such being indicative of the occurrence of a seizure;
• and
• output means for producing an output before the onset of electroencephalographic waves of said input signals indicating the impending occurrence of the seizure.

A method of detecting the occurrence of abnormal activity in the brain of a subject, said method comprising the steps of:

• (a) receiving into a signal processor input signals indicative of the subject's brain activity;
• (b) determining at least one ictal component in said input signals;
• (c) measuring the ictal activity indicated by said at least one ictal component in a foreground epoch of said input signals to produce a foreground measure of said ictal activity;
• (d) determining whether said ictal activity of said foreground measure is indicative of the occurrence of said abnormal activity;
• and
• (e) performing steps (a)-(d) while said ictal activity is occurring before the onset of electroencephalographic wave signals of said abnormal activity.

A method of detecting the occurrence of abnormal activity in the brain of a subject, said method comprising the steps of:

• (a) receiving into a signal processor input signals indicative of the subject's brain activity;
• (b) determining at least one ictal component in said input signals;
• (c) measuring the ictal activity indicated by said at least one ictal component in a foreground epoch of said input signals to produce a foreground measure of said ictal activity;
• (d) determining whether said ictal activity of said foreground measure is indicative of the occurrence of said abnormal activity;
• and
• (e) performing steps (a)-(d) while said abnormal activity is occurring before the onset of electrocorticogram wave signals of said abnormal activity.