Memory functioning in panic disorder : a neuropsychological investigation

Recent psychological and neurological studies of patients with anxiety disorders suggest that memory functioning may be impaired in patients with panic disorder. The suggested means by which memory may be impaired, however, differs among the various areas of study. Some studies have reported attentional disturbances among patients with anxiety disorders, thus suggesting that memory may be impaired secondary to distractibility. Neuroimaging studies, on the other hand, have reported abnormalities in temporal lobe structures of patients with panic disorder who panic in response to sodium lactate infusion, suggesting that memory may be impaired secondary to temporal lobe dysfunction. Moreover, abnormalities reported by the majority of imaging studies have been lateralized to the right temporal lobe, suggesting that memory for visual material may be more impaired than memory for verbal material. Twenty-five subjects with a primary diagnosis of panic disorder were administered a test battery consisting of neuropsychological measures of memory functioning, standard measures of intellectual functioning, and self-report measures of emotional functioning. Twenty-five normal subjects and 25 subjects with a primary diagnosis of major depression served as controls. Groups were matched for age, education, and gender. Multivariate analyses of memory test scores revealed that subjects with panic disorder performed significantly worse than normal controls on measures of visual learning, and significantly worse than both normal and depressed controls on measures of visual recall. Panic disorder subjects did not differ from normal controls on measures of verbal learning, verbal recall, or attentional capacity. Panic disorder subjects performed significantly better than depressed subjects on measures of verbal recall, but were no different on measures of verbal learning or attentional capacity. No relationship was found between test performance and the self-reported tendency of patients with panic disorder to focus attention on internal bodily sensations or concerns. Similarly, no relationship was found between memory test performance and severity of panic disorder; however, a significant negative relationship was found between attentional capacity and severity of illness. Results provide evidence for a neuropsychological correlate to panic disorder and are discussed within the context of recent psychological and neurological models of panic