Lecture 3: Flashcards
What is a major limitation of neuroimaging techniques like fMRI and PET?
It shows correlation, not causation—activity may be related but not necessarily essential for behavior.
What are non-essential activations in brain imaging?
Brain regions may be active but not necessary; could be involved in learning, support, or co-occurring actions.
How can we determine causality in brain function?
By disrupting brain activity (e.g., via lesion, stroke, trauma, or TMS) and observing behavioral changes.
What is neuropsychology?
The study of how brain damage affects cognition and behavior.
Why is neuropsychology valuable?
It identifies brain regions necessary for specific cognitive processes.
Who was Paul Broca and what did he discover?
French neurologist who found that damage to the left inferior frontal cortex impairs speech (Broca’s area).
What is clinical neuropsychology?
An applied field diagnosing and treating behavioral effects of brain damage in medical settings.
What does Broca’s area control?
Speech production; damage causes expressive aphasia.
What is Wernicke’s aphasia?
Fluent but nonsensical speech with poor comprehension.
What is the corpus callosum?
A bundle of white matter connecting the brain’s hemispheres.
What did split-brain studies reveal about language?
Language is predominantly localized in the left hemisphere.
Who was H.M. and why is he important?
A patient with removed medial temporal lobes; he had severe anterograde amnesia, highlighting the hippocampus’s role in memory.
What memories were preserved in H.M.?
Working memory, procedural memory, and early childhood memories.
What is hemispatial neglect?
Inattention to the left side of space, often after right hemisphere stroke.
What causes neglect in visual fields?
Possibly biased attention, disrupted spatial representation, or impaired motor initiation—likely multifactorial.
What is a single dissociation?
When one function (e.g., vowels) is impaired but another (e.g., consonants) is spared.
Why is a single dissociation not conclusive?
It may just reflect differences in task difficulty or resilience.
What is a double dissociation?
Opposite deficits in different patients, proving functions are distinct (e.g., vowels vs. consonants).
What did Cubelli’s study show?
Patients could write consonants but omitted vowels, supporting different processing systems.
What is the main strength of neuropsychology?
It allows causal inference by examining real brain damage.
What is a limitation of studying brain lesions?
Lesions are rarely selective and may affect multiple areas or general cognition.
What is TMS?
A non-invasive magnetic stimulation method to temporarily disrupt cortical function.
How does TMS work?
It uses a magnetic field to induce electric currents in neurons, disrupting activity.
What are some effects of TMS?
Can cause finger twitches (motor cortex) or phosphenes (visual cortex).
What is a “virtual lesion”?
A temporary disruption in brain function caused by TMS.
What is the spatial resolution of TMS?
Typically 10–20 mm; depends on scalp distance and regional connectivity.
What is the temporal resolution of TMS?
High—can determine the exact timing of brain region involvement.
What can be inferred from TMS?
Whether a region is essential for a task and when it is involved in processing.
Why are control conditions needed in TMS studies?
To account for sensations and sounds from the TMS pulse.
What are TMS limitations?
It cannot reach deep brain structures, has subtle effects, and carries a small seizure risk.
