qeeg Neuroshow

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QEEG Quantitative 

Electroencephalography

 The QEEG is a painless and non-invasive procedure which begins with data collection. The scalp is prepared and measurements are calculated.

 A stretchable elastic electrode cap is slipped onto the head, and the recording electrodes  filled with a water soluble contact gel. 

Brain waves are then recorded onto the computer while the client relaxes with eyes closed and with eyes  open. 

The brain waves are compared to a computer library of brain waves from medically, neurologically, and psychologically evaluated normal subjects. 

Broadman Areas and Brain Functions

EEG Absolute Power Z scores examines many relationships between the various brain wave frequencies. 

Relative Power answers the question:  

“Is performance potential restricted because some brain wave frequencies are deficient  or other frequencies excessive?

Relative Power answers the question:  

“Is performance potential restricted because some brain wave frequencies are deficient  or other frequencies excessive?

Asymmetry looks at voltage differences between brain areas, and  answers the question: “Are electrical impulses in these regions excessively high or deficiently low for good performance?

 Coherence analyzes how much energy the brain is sharing between different areas. Coherence answers the question: “How efficient is my brain’s ability to communicate with itself?”

Phase measures the speed of electrical signals moving across the brain's surface. Phase answer the question: “Is the brain's energy moving at the optimal speed for adequate to superior performance?

Topographic Brain maps answer the questions: “Are brain frequencies and patterns appropriate for the task?” “Are the proper brain areas engaging to yield maximum performance?”

LORETA Z Scores provide 3 dimensional perspectives of brainwave activity from deep within the brain.

Tramatic Brain Injury and Severity Analysis

Learning Disabilities Discriminate Analysis

Spectrum Brain Wave Analysis examines various frequencies and regions over time and answers the question, “Does this brain switch to a new task in an appropriate, easy and efficient way?”

Excessive slow waves with relatively deficient fast frequencies reduce our ability to focus and pay attention.

Excessive fast frequencies combined with relatively deficient Alpha and Theta waves may increase feelings of anxiety.

Unequal brain wave energy between the two sides of the brain may restrict our ability to think clearly and may be associated with feelings of depression.

Excessive coherence can produce lack of differentiation in certain regions and could indicate mild head injury from birth trauma or stroke.

QEEG Quantitative

Electroencephalography

EEG characteristics are graded for performance efficiency in four categories: Relative Power, Asymmetry, Coherence, and Phase.

Topographic Brain maps answer the questions: “Are brain frequencies and patterns appropriate for the task?” “Are the proper brain areas engaging to yield maximum performance?”

EEG characteristics are graded for performance efficiency in four categories: Relative Power, Asymmetry, Coherence, and Phase.

Asymmetry looks at voltage differences between brain areas, and answers the question: “Are electrical impulses in these regions excessively high or deficiently low for good performance?

The magnitude (the energy of each frequency group at the 19 electrode sites) and the relationship between the brain's various frequencies are calculated for efficiency.

The caudate nucleus as an element of the Executive System of the Brain

• The caudate nucleus receives inputs from the whole association cortex of the human brain

Specialization of cortical areas (reading and hearing)

• The PET scan on the left shows two areas of the brain that become particularly active when volunteers read words on a video screen: the primary visual cortex and an additional part of the visual system, both in the back of the left hemisphere.

• Other brain regions become especially active when subjects hear words through ear-phones, as seen in the PET scan on the right.

Damage to Cortical Visual Areas

Occipital lobe: problems associated to damage

• Defects in vision (Visual Field Defects, Scotomas).

• Difficulty with identifying colors (Color Agnosia).

• Production of hallucinations

• Visual illusions - inaccurately seeing objects.

• Word blindness - inability to recognize words.

• Difficulty in recognizing drawn objects.

• Inability to recognize the movement of an object (Movement Agnosia).

• Difficulties with reading and writing.

• Damage to one side of the occipital lobe causes homonomous loss of vision with exactly the same "field cut" in both eyes

Temporal lobe: problems associated to damage

• Difficulty in recognizing faces (Prosopagnosia).

• Difficulty in understanding spoken words (Wernicke's Aphasia).

• Disturbance with selective attention to what we see and hear.

• Difficulty with identification of, and verbalization about objects.

• Short-term memory loss.

• Interference with long-term memory

• Increased or decreased interest in sexual behavior.

• Inability to catagorize objects (Catagorization).

• Right lobe damage can cause persistant talking.

• Increased aggressive behavior.

Frontal lobe: problems associated to damage

• Loss of simple movement of various body parts (Paralysis).

• Inability to plan a sequence of complex movements, such as making coffee (Sequencing and Short Term Memory impairment).

• Loss of spontaneity in interacting with others (Abulia).

• Loss of flexibility in thinking, persistence of a single thought (Perseveration).

• Imitative and utilization behavior.

• Inability to focus on task (Attending).

• Changes in social behavior, in personality, in mood (Emotionally Labile)..

• Inability to express language (Broca's Aphasia).

Prefrontal cortex: functions

• Planning of behavior (including social)on the basis of integration of sensory and verbal information, emotions and internal state.

• Setting ideas, schemes, goals.

• Maintaining of working memory

• Inhibitory control

Basal ganglia-thalamo-cortical loop

• The basal ganglia, substantia nigra, subthalamic nucleus are the elements of cortico-subcortical loop that mediate control of sensory, motor and cognitive functions. This control includes working memory and executive functions.

Cortico-hippocampal loop

• This loop is implicated in emotional processing and consolidation of episodic memory.

Lateral Prefrontal Cortex: Working memory

• Lateral prefrontal cortex provides a transient buffer for sustaining information stored in other cortical regions. In this example, the person is telling a friend about her work across the Golden gate Bridge. Long-term memories are stored in specific cortical areas and are activated by the LPC.

Frontal cortex: inhibition

Short-latency auditory evoked potentials reveal filtering deficits in patients with lesions in the lateral prefrontal cortex.

Top: No change in patients with parietal lobe lesions.

Middle: Reduction in patients with temporo-parietal damage, reflecting the loss of neurons in auditory cortex.

Bottom: Amplification in patients with frontal damage, suggesting a loss of inhibition from frontal lobe to temporal lobe.

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