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The right posterior superior temporal sulcus (pSTS) shows a strong response to voices, but the cognitive processes generating this response are unclear. One possibility is that this activity reflects basic voice processing. However, several fMRI and magneto encephalography findings suggest instead that pSTS serves as an integrative hub that combines voice and face information. Here we investigate whether right pSTS contributes to basic voice processing by testing Faith, a patient whose right pSTS was resected, with eight behavioral tasks assessing voice identity perception and recognition, voice sex perception, and voice expression perception. Faith performed normally on all the tasks. Her normal performance indicates right pSTS is not necessary for intact voice recognition and suggests that pSTS activations to voices reflect higher-level processes.

Previous neuroimaging research has shown that the cerebellum is often activated during autobiographical memory (AM) retrieval. However, the reliability of that activation, its localization within the cerebellum, and its relationship to other areas of the AM network remains unknown. The current study used Activation Likelihood Estimation meta-analysis (ALE) as well as resting-state and task-related functional connectivity analyses to better characterize cerebellar activation in relation to AM. The ALE meta-analysis was run on 32 neuroimaging studies of AM retrieval. The results revealed a cluster of reliable AM-related activity within the Crus I lobule of the right posterior cerebellum. Using the peak ALE coordinate within Crus I as a seed region, both task-related and resting state functional connectivity analyses were run on fMRI data from 38 healthy participants. To determine the specificity of connectivity patterns to Crus I, we also included a cerebellar seed region in right Lobule VI previously identified in an ALE meta-analysis as associated with working memory. Resting-state functional connectivity analyses indicated that Crus I was intrinsically connected with other areas of the AM network as well as surrounding and contralateral cerebellar regions. In contrast, the Lobule VI seed was functionally connected with cerebral and cerebellar regions typically associated with working memory. The task-related connectivity analyses revealed a similar pattern, where the Crus I seed exhibited significant connectivity with key nodes of the AM network while the Lobule IV seed did not. During a semantic control task, both Crus I and Lobule VI showed significant correlations with a network of regions that was largely distinct from the AM network. Together these results indicate that right Crus I lobule is reliably engaged during AM retrieval and is functionally connected to the AM network both during rest, and more importantly, during AM retrieval.

Transcranial magnetic stimulation (TMS) is particularly useful in teasing apart the contrasting contributions of different anatomical and functional systems in particular aspects of behaviour, for example the involvement of the dorsal and ventral visual streams in tasks involving the perception of distance, shape and colour. In order to investigate the dual involvement of two areas, namely right posterior parietal cortex (PPC) and lateral occipital cortex (LO), in a distance discrimination task, neural processing in both areas was concurrently disrupted using dual site TMS. Although there was no change in error rates, reaction time was significantly lengthened over that seen with TMS over either site alone. This additive effect indicates that both PPC and LO are concurrently active and essential for efficient processing of this task. The second experiment investigated the specificity of function within the ventral stream. Performance was assessed for distance and shape discrimination when TMS was applied to our original LO site and an area rostral to V5 but still part of the lateral occipital complex (rostral LOC) that is activated in form and colour discrimination. Performance deficits were restricted to TMS over LO; no significant impairment for either task followed TMS at the rostral LOC site.

One function of the posterior parietal cortex (PPC) is to monitor and integrate sensory signals relating to the current pointing direction of the eyes. We investigated the possibility that the human PPC also contributes to spatial updating during larger-scale behaviors. Two groups of patients with brain injuries either including or excluding the right hemisphere PPC and a group of healthy subjects performed a visually-directed walking task, in which the subject views a target and then attempts to walk to it without vision. All groups walked without vision accurately and precisely to remembered targets up to 6 m away; the patient groups also performed similarly to the healthy controls when indicating egocentric distances using non-motoric responses. These results indicate that the right PPC is not critically involved in monitoring and integrating non-visual self-motion signals, at least along linear paths. In addition, visual perception of egocentric distance in multi-cue environments is immune to injury of a variety of brain areas.

The non-visual updating of body-centred spatial relationships was investigated in an experiment in which blindfolded patients had to point to previously seen targets after a body rotation in the absence of vision. Patients with lesions to the right dorsal (RD) area were impaired at updating their positions relative to non-RD patients and normal subjects: they tended to underestimate systematically the angle through which they had turned. The results are interpreted in terms of impoverished locomotor input and/or systematically biased processing or locomotor proprioception in the RD patients, which prevented accurate tracking of changes in egocentric spatial relationships.

Groups of patients with cortical lesions were subjected to uniquely developed procedure to test auditory-spatial perception. The stimuli were comprised of a sound source, which sequentially outlined a pattern within a 10×10 matrix of loudspeakers. Simple sound patterns, which “moved” across the loudspeaker array only once or twice, were equally well identify by the control group and the various patient groups. However, the more complex patterns, which outlined the contour of alphabetical letters, resulted in significantly lowered identification rates for the patient groups with lesions in the right posterior, left posterior and left temporal lobes. As a control measure, visual-spatial tasks were administered, and lower performance rates were found for the left and right posterior groups. The differences and similarities between auditory-spatial and visual-spatial processing are discussed.

A double dissociation of visual and spatial performance is reported in two men with chronic focal missile injuries of the right cerebral hemisphere. The clinical, neuropsychological and post-mortem anatomical data are considered in relation to evidence from physiological research of two major cortico-cortical pathways for object-recognition and spatial perception.

Patients with right posterior cerebral injuries did more poorly than patients with other unilateral injuries and normal control subjects in recognizing different faces. When the faces were presented upside-down, however, those with the other unilateral injuries did worse than the right posterior group and the normal controls. This dissociation between upright and inverted presentations was not found with pictures of another common object, houses of similar architecture. The results support the notion that, among the disorders caused by right posterior injuries, there does exist a material-specific deficit in recognizing faces.

Seventy-nine patients with different cerebral lesions were trained on a visually- guided stylus maze. The main findings were: (1) bilateral hippocampal lesions produced the most severe impairment, with one patient showing no progress in 215 trials; (2) right temporal lobectomy produced a significant deficit, particularly when the underlying hippocampus was radically excised, whereas patients with left temporal-lobe lesions of equal extent, or with small parietal-lobe lesions of either hemisphere, obtained normal scores; (3) larger lesions of frontal or right posterior cortex severely impaired maze learning, suggesting that size as well as locus of cortical lesion may be a factor in maze-performance; (4) only frontal-lobe lesions affected the ability to follow test instructions.

Men with right, left and bilateral cerebral lesions were required to make right/left judgements under two experimental conditions, in one of which a mental re-orientation of the stimulus was presumed to be required. Schematic drawings of a man were exposed in either an upright or inverted position and, on each trial, one of the hands was marked. The subject's task was to say “right” or “left” depending on the hand marked. The right posterior group made fewer errors than the left posterior group under the upright condition but significantly more under the inverted condition. This result is attributed to their failure to perform an appropriate mental rotation of the inverted stimuli.